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Full text of "Radio broadcast .."

From the collection of the 



Z 

Pre 



sling 






ibrary 

P 



San Francisco, California 
2007 




MAY 1924 




BSQADC 

Building a Resistance-Coupled Amplifier 

"Who's To Pay?" $500 Prize Contest 

"As It Was In The Beginning" 



Reflexing Your "Blooper" 






complete 




C-300 6 Volts Gas 

Content Detector 

S5.00 



C-301H 6 Volts 
:iTn]i. Amplifie 

ss.oo 




RADI0 TUBES 

FOR EVERY TYPE OF RECEIVING SET 



WHATEVER type of receiving set or 
circuit you are using one or more of 
these five Cunningham receiving tubes will 
be ideal for obtaining maximum distance 
reception with perfect reproduction of both 
voice and music. 

Three of the flve tubes are designed to 
use dry batteries for filament lighting. 
C-299, the latest development in Radio 
Tubes, is compact in design and highly 
efficient in operation as a radio frequency 
amplifier, a detector and as an audio-fre- 
quency amplifier. When used for the lat- 
ter purpose, the Output of two stages is 
sufficient for the operation of a small loud 
speaker. 

The most remarkable feature of this tube 
is the new patented filament used which 
draws only .06 amperes at 3 volts. 
C-ll is a dry battery tube with a special 
base for use in sets having special sockets. 
It is a good detector and audio-frequency 
amplifier. The filament is lighted from 
a single dry battery and draws .25 amperes. 
C-12 is identical to C-ll in operating 



characteristics, but is mounted on a stand- 
ard base to permit the use of a dry bat- 
tery tube in sets equipped with standard 
sockets without the aid of special adaptors. 
Whenever storage battery supply is avail- 
able for filament lighting, the C-300 will 
be the best tube to use as a detector be- 
cause it is the most sensitive for the re- 
ception of distant and weak signals. 
Under the same condition, C-301A will be 
the best tube for amplification at either 
radio or audio frequency, because it gives 
greater gain per stage than any other tube 
on the amateur market. The new patented 
filament used, similar to that in C-299 
draws only .25 amperes at volts, re- 
ducing the necessity of frequent storage 
batten' charging. 
Patent l\Intir Cunningham tubes are 

ratent notices ,, )V ,. n ,,i i, y patents 

dated 2-18-08 and others issued and pend- 
ing. Licensed for amateur, experimental 
and entertainment use in radio communi- 
cation. Any other use will be an infringe- 
ment. 



The can mul nin rution of un-li model of Rcci-iriiiii Tnln in fnllii rsitlitinrtt 1:1 our mir 
1,0-jiage "Radio Ttibi Data Book." Copies man be obtained by WMfo0 /<; erntg to 
'nir .Sflrt Francisco office. 



Home Office: 182 Second St. 
San Francisco, Calif. 



154 West Lake Street 
Chicago, Illinois 



30 Church Street, New York City, N. Y. 




Tested and approved by RADIO BROADCAST -^ 

432475 DEC 8 
Bbmif 

Periodical 



RADIO BROADCAST 



VOLUME V 

MAY, 1924, to OCTOBER, 1924 



BETTER RADIO 




GARDEN CITY NEW YORK 

DOUBLEDAY, PAGE & COMPANY 

1924 



Copyright, 1924, by 

DOUBLEDAY, PAGE & COMPANY 



RADIO BROADCAST ADVERTISER 




the new Radiolas / 




oVeu? Triumphs of T^adio Invention- 
Wew Performance Records 



>e }fiere's a 'Radaola fir every purse" 

$35 to $425 



t Model 



Price 



Approximate 
Range 



Type of 
Antenna 



Degree of 
Selectivity 




Radiola III 

With two WD-11 
Radiotrons* and head 
telephones 



$35 



Jp to 1500 miles 
vith headphones. 
Local stations on 
Loudspeaker. 



Outdoor or in- 
door antenna. 



Improved 
selectivity. 
Minimum 
radiation. 




Radiola Balanced 
Amplifier 

To be used with Rad- 
iola Ill.With two WD- 
II Radiotrons.* 



$30 



Gives Loud- 
speaker operation 
with Radiola III 
up to 1500 miles 
under favorable 
conditions. 



Outdoor or in- 
door antenna. 



Radiola III-A 

with four WD-11 Rad- 
iotrons,* head tele- 
phones and Radiola 
Loudspeaker. 



$100 



Same without Loud- 
speaker. 



$65 



Loudspeaker op- 
eration up to 1500 
miles under fa- 
vorable condi- 
tions. 



Outdoor or in- 
door antenna. 



Improved 
selectivity. 
Minimum 
radiation. 



Radiola 
Regenoflex 

with four WD-11 Rad- 
iotrons,* and Radiola 
Loudspeaker. 

Same without Radio- 
trons or Loudspeaker. 



$206 
$150 



Loudspeaker op- 
eration up to 2000 
miles under fa- 
vorable condi- 
tions. 



Outdoor or in- 
door antenna. 



Extraordi- 
nary selec- 
tivity. Non- 

radiatine. 




Radiola X 

with four WD-11 
Radiotrons.* Loud 
speaker built-in. 



$245 



Loudspeaker op- 
eration up to 200C 
miles under fa 
vorable condi- 
tions. 



Outdoor or in- 
door antenna. 



Extraordi- 
nary selec- 
tivity. Non 
radiating. 




Radiola 
Super- Heterodyne 

with six UV-199 Radio- 
trons* and Radiola 
Loudspeaker. 



$286 



Same without Radio- 
trons or Loudspeaker. 



$220 



Loudspeaker op- 
eration up to 2000 
miles with inter- 
nal loop. 'With 
external loop up 
to 3000 miles un- 
der favorable 
conditions. 



No antenna. 
(Concealed 
small loop built 
into set.) 



Super-selec- 
tivity. Non- 
radiating. 




Radiola 
Super -VIII 

with six UV-199 
Radiotrons.* Loud- 
speaker built-in. 



$425 



Loudspeaker op- 
eration up to 3000 
miles under fa- 
vorable condi- 
tions. 



No antenna. 
(Concealed 
large loop built 
into set.) 



Super-selec- 
tivity. Non 
radiating. 



t All Radiolas sold without batteries. 



* Only dry batteries used. 



Radio Corporation of America 
Sales Offices : 233 Broadway, New York 
10 So. La Salle St.. Chicago, III. 433 California St., San Francisco, Cal. 

Radiola 



SeiMkthm coupon for an iiliiRti'ated booklet x 
that 4t-1Is the story completely, with detailed \ 
description of evei-y set 



REG. U.S. PAT OFF 



RADIO CORK OF AMERICA 
Dept. 35. [Address office nearest you] 
Please send me your new free Radio 
Booklet. 



Na 



Tested and approved by RADIO BROADCAST 




IN LONDON 

mile away 



RADIO 
BROADCAST 



Vol. 5, No. i 




May, 1924 



Home Remedies for Indisposed 

Receivers 

The Simplicity of Good Grounds and Good Antennas. Getting the Bought 
Set into Action. Where Trouble May Lie and How to Eliminate It 

By WILLIAM H. GARY, Jr. 

This is the natural sequel to last month's article, "How to Go About Buying a Set." 
It is written primarily for those who know little or nothing about radio, but who have 
acquired sets from which they expect good results. Unless you are familiar with the 
installation and care of broadcast receivers, and unless you know how to diagnose and 
remedy certain simple ills that beset practically every radio set at one time or another, you 
are likely to think broadcast receiving a very confused and unsatisfactory hobby, indeed. 

We are continually coming in touch with people who are balked by elementary details 
who could increase the effectiveness of their receivers 100 per cent, by proper installation 
and adjustment of them; and perhaps more often still we find people who are prevented, 
by difficulties existing only in their own imaginations, from getting the best service 
from their newly acquired sets. This article is not a theoretical discussion: it is based on 
actual "cases," and on cures which are known to work. THE EDITOR. 



r WOULD give an impression of pessimism 
ivhich it is not the writer's intention to 
:reate, were he to plunge directly into the 
subject of treating sick sets, after discus- 
sing last month the purchase of brand-new 
apparatus. Still, new babies need careful 
treatment if they are to be kept in health; the 
fact that they are new does not make them im- 
mune to a number of elementary indispositions. 
The missing link in the chain of events from the 
purchase of a broadcast receiver and acces- 
sories, to apply first-aid remedies, is, of course, 
the assembly of the apparatus and its proper 
manipulation to get many a distant station 
and many a quiet evening (yes, it's possible) 
at home. 



You were reminded last month that a thor- 
ough study of the instructions issued by the 
manufacturers of most sets, and the active 
help of some acquaintance who is familiar with 
receivers, will help greatly in starting you 
happily on your way. It is a pity that neither 
booklets nor acquaintances, however, always 
disclose the things you most want to know, in 
terms that resemble plain English. 

GOOD AND BAD GROUNDS 

A CASE in point is the installation of the 
antenna and the "ground." Every 
broadcast listener knows that a wire attached 
to the ground post on the set "goes" to the 
water-pipe or radiator (or any conductor which 






Radio Broadcast 



has connection with the earth). The trouble 
is, too many wires "go" and too few get there 
completely. A space of one thousandth of 
an inch may separate the conducting part of 
the wire from the conducting part of the pipe 
or "ground" to which it is attached. And 
electrically speaking, one thousandth of an 
inch may be as unbridgeable as the Grand 
Canyon. 

The other day, a man installed a new set 
for himself which did not work. He thought 
the clerk in the store must have given him bad 
tubes or batteries, and his maledictions fell 
upon his silent and shiny cabinet. But it 
was found that he had not scraped clean the 
surface of the waterpipe nor the wire which he 
had attached to it; and when one of his friends 
gently pulled the wire, its several turns un- 
wrapped themselves, and the wire came off in 
his hands! Here is what the man should have 
done: 

Scraped both wire and pipe, and 
i Soldered the wire to the pipe; or 
2 Connected the wire to the pipe firmly 
with a ground clamp (costing about ten cents 
at any radio store): or 

3 At least wrapped four or five turns of 
cleaned wire round 
the pipe, drawn it up 
tight by twisting 
with a pair of pliers, 
and bound up the 
connection with 
"electrician's tape" 
or adhesive plaster. 

This is all the 
broadcast listener 
need know about 
grounds, except that 
the conducting path 
from set to earth 
should be as short as 
it can conveniently 
be made, and it is 
best not to use wire 
smaller than No. 14. 



TWO WAYS OF FOR- 
GETTING ABOUT YOUR 
ANTENNA 




lowing procedure in putting up an antenna 
is simple and adequate: through one hole 
in one of your small insulators tie a piece of 
rope (or cord or wire) and fasten one end of 
your antenna wire securely through the other 
hole. Attach the rope end anywhere, so long 
as it will allow from 50-125 feet of the antenna 
wire to swing clear (as high as possible above 
the roof or the earth) when the wire is run 
through a second insulator likewise firmly 
suspended from any convenient object and 
down into the room where you have your set. 
A lightning arrester, useful principally to save 
your insurance should your house be struck 
by lightning (though a radio installation does 
not make this more likely), generally consists 
of a fuse with two binding posts on it. The 
antenna lead-in wire goes to one binding post, 
on its way to the set, and the ground lead goes 
to the other post, on its way to the set 
['"Where does this road go?' inquired the 
stranger. 'Doesn't go, it stays right here,' said 
the native." Yes, we stand corrected; but 
the figure of speech is convenient and clear.] 
Some types of arrestors require a slight 
variation from the above hookup. 1 nstructions 
regarding the installation of lightning arresters 

are usually included 

with them. 



TOO MANY GROUND WIRES "GO" AND 
TOO FEW GET THERE COMPLETELY 

IT IS also common 
knowledge that an antenna installation 
consists of a conducting material (wire) in- 
sulated from the ground and leading in to 
the proper binding post on the set. The fol- 



A PORCELAIN 
j[\ tube insulator 
inserted in a hole 
drilled through a cor- 
ner of the window 
frame is the most- 
used method of keep- 
ing the antenna in- 
sulated at the point 
where it enters the 
house. 

An antenna need 
not be erected out- 
of-doors. If you can 
run as much as forty 
feet of wire through 
several rooms and a 
hall, for instance, 
more or less in a 

straight line, you are likely to get signals, 
although not so loud as with a higher and 
longer antenna. 

It is by no means necessary to have a 



Home Remedies for Indisposed Receivers 



separate lead-in wire attached to the main part 
of the antenna. In fact, this requires an extra 
connection one more place that may cause 
electrical loss. If you must have a separate 

piece of lead-in wire 

if someone has per- 
suaded you that a 
length of heavy, in- 
sulated copper wire 
is the "without 
which not" of suc- 
cessful reception, do 
not make the mis- 
take of the following 
"case" (He happened 
to be, or just natur- 
ally was however 
you may look at it 
the same novice who 
made the easy-come, 
easy-go ground con- 
nection, referred to 
above) : 

Everything seemed 
to be O. K. Signals 
were audible, in fact; 
but they faded en- 
tirely at times, and at other times were su- 
spiciously faint. 

" I suppose your antenna system is all right," 
said the friend who was still trying to locate the 
trouble, after having fixed the ground connec- 
tion. 

"Oh, yes good antenna. It must be the 
bat 

" Let's take a look at the antenna." 

And so they did. 

Up went the window and out went two heads. 
One head saw nothing particular to write home 
about, but the other saw this: the upper end of 
the lead-in wire sliding gently back and forth 
along the corroded surface of the antenna, in 
the wind! It is to the friend's credit that he 
restrained his mirth and broke the news with 
enviable courtesy to the perpetrator of the 
installation. 

What should the owner of the set have done 
in the first place? He should have: 

i Used only one piece of wire for both 
antenna and lead-in; or 

2 Soldered the lead-in to the antenna; or 
3 At least, scraped two inches of the an- 
tenna wire and two inches of the end of the 
lead-in, twisted them tightly together (not 
merely wrapped the lead-in about the antenna) 




and bound up the wound with friction tape to 

prevent infection. 
The same care should be used in joining any 

wires, without solder, in a radio circuit. Many 

and pathetic are the 
ways in which begin- 
ners and sometimes 
others connect wires 
together. The writer 
has seen one loop of 
wire encircling an- 
other loosely, taped, 
and called a joint. 
The idea seemed to 
be merely to hold the 
two wires from pul- 
ling apart, not to 
provide a free path 
for the flow of elec- 
tric current. The 
commonest case of 
poor splicing is that 
of one wire twisted 
round another wire 



AND SO THEY LOOKED AT THE ANTENNA 



which is left straight 
Oh, it works some- 
times. 

One advantage of installing your ground and 
antenna in the careful manner described is that 
when something "goes wrong" with your set, 
you do not have to run up on the roof to look 
over the antenna, or get down on your knees 
by the water or radiator pipe to examine 
the "ground." You can dismiss these factors 
from your mind. And it is just as well, for 
there may be other things to think of. 

NOW ABOUT THE BATTERIES 

ONE of the most useful instruments in any 
radio first-aid kit is a B battery volt- 
meter. It ranks next in importance to pliers, 
jack-knife, and screw-driver. Good volt- 
meters reading from o to 50 volts, may be had 
for about $2.50 When a 22^-volt B battery 
falls below about 1 5 volts, you had better 
replace it. Sometimes, you will get no "kick" 
out of a B battery at all, or it will move the 
voltmeter needle only slightly. It has died 
in service and there is no use keeping it. Often, 
when a B battery is low or dead, an indication 
of its condition is seen in a damp spot on the 
side, where the electrolyte has leaked through, 
or by a bulging of the insulating compound on 
top of the battery Your detector B battery 
voltage should be at least 16 and generally 



Radio Broadcast 



cannot be allowed to fall far below 20. If the 
B battery voltage supplied to the amplifier 
tubes should fall below 40, it is well to add more 
"juice" or replace the low units with new 
ones. 

Your A battery whether it be dry cells or 
storage battery is serviceable until you find 
that even when you turn the lights up as far 
as the rheostats will allow, the signal is not so 
loud as you have a right to expect. It is a good 
rule to burn your tube filaments as low as you 
can, still getting sufficient volume; it saves 
your batteries and reduces distortion. 
It is advisable to hook up your bat- 
teries in this way: d) connect the 
two wires from the A battery to the 
-f-and A posts on the set; (2) con- 
nect either the+or the -wire from 
the B battery to its proper post on the 
set; (3) place the tubes in their soc- 
kets, turn up the rheostats (also snap 
on the battery switch if there is one), and see if 
the tubes light: (43.) if so, connect the other B 
battery lead and all will be well: (4b) if not, 
look over the wiring and see that all connections 
are correct and good (If the tubes do not seem 
to make firm contact in their sockets, take the 
tubes out, bend up the socket prongs with your 
finger.) This procedure may save you the price 
of the tubes you are unlucky enough to leave in 
their sockets when the B battery current runs 
along the path reserved for the A battery. 

AS FOR THE REST OF IT. . . 

AS FOR the business of tuning, there is little 
f\ that can be said which will be of half so 
much use to the novice as two or three even- 
ings' practice in adjusting his set. He will 
soon get the "feel" of it, and learn how to cut 
out as much interference, static, and other 




noise as is possible, without diminishing the 
signal strength too much. 

If you are using two or more tubes of the 
same type, try interchanging them and then 
readjusting the rheostats and other controls. 
This often results in a considerable increase in 
signal strength. 

When a set goes dead, with antenna and 
ground connections as they should be, with 
batteries well up, and tubes hitting on all four, 
.trouble may possibly be located in the jacks, 
or in the phones, or in a broken connection else- 
where in the set. The jack springs 
should be inspected: does the tip 
of the plug make contact with the 
proper spring? does the side of the 
plug fit snugly against the side of 
the jack? do the springs which are 
displaced by the tip of the plug 
make (or break) their contacts as 
they should? 
The test for phones is simple: put them on; 
touch the tip of the plug (or one phone tip) to 
one terminal of a dry cell, and touch the sleeve 
of the plug (or the other phone tip) to the other 
terminal: a click should result. "No clickee, 
no workee." 

If you have done ah this, and have looked in 
vain for a loose or broken connection, it is then 
time to secure the assistance of someone 
familiar with the more serious ailments of re- 
ceiving sets. But the chances are that this 
will not be necessary. If you had trouble at 
first, and started reading this article, you will 
probably have located your trouble and ap- 
plied the remedy a page or so ago. Instead 
of reading these words you will have abandoned 
them for the serious business of bringing ' v 
the programs that float so freely through thh 
countrv's air. 



A Plea to Announcers 

Many letters have come to RADIO BROADCAST and many more have been received by broadcasting 
stations complaining that station announcers announced too indistinctly or too infrequently. This card was 
recently sent out by the National Association of Broadcasters to all their member stations. THE EDITOR. 

STATION ANNOUNCERS 

Numerous complaints have recently come to us of announcers failing to give their call letters at the end of 
each program event. D.X. fans are especially aggravated. 

Local listeners know your station, but hundreds of thousands of long distance listeners on the air each 
night, do not. 

Call letters given immediately after an event and repeated again at the conclusion of announcement arc 
appreciated by these people. 

THE NATIONAL ASSOCIATION OF BROADCASTERS 

1265 BROADWAY, NEW YORK CITY 



Reflexing Your Single Circuit Receiver 

Various Circuits and What They Mean 

PART VI 
By ZEH BOUCK 

There are only a few of our readers to whom RADIO BROADCAST has preached, in vain, 
the evils of regenerative single circuit tuners. But many owners of single circuit apparatus 
protest against junking equipment in which they have invested, perhaps, hundreds of dollars. 
There is a certain justness in their point of view. However, there is no necessity for re- 
legating the single circuit regenerator to the ash-can. They can be made over, at a very 
small expense, and with an increase in efficiency into the "Knock-out" reflex circuit that 
has taken our readers by storm. 

Mr. Bouck tells how to do it. THE EDITOR. 



M 



UCH has been said and written 
condemning the single circuit 
regenerative receiver. So vehe- 
ment has been the reaction 
against radiating (not eradia- 
ting) receivers, which, like the spark trans- 
mitter, has lived its day that was genuinely 
useful, that there are a very few, even among 
the manufacturers, who fail to appreciate and 
proclaim the iniquity of such oscillators. But 
regardless of the universal appreciation of the 
several faults of single circuit tuners and the 
sincere desire to remedy them, the propaganda 
against them has been mostly destructive, ex- 
cept for advocating a complete change in re- 
ceiving equipment. The manufacturers have 
quite profitably backed this advice by placing 
on the market, at the psychological moment, 
non-radiating equipment. But there are many 
of us who, urged by these same manufacturers 
only a few months 
back, invested our en- 
tire radio budget in 
the receivers that they 
now condemn, and 
who must necessarily 
hesitate before making 
the change that means 
so much to general 
and individual radio 



improvement. 

While several sub- 
stitutes have been sug- 
gested for the offend- 
ing circuits straight 
radio-frequency am- 
plification, the neutro- 



What You Need to Build the "Reflexit" 

IF YOUR set is a single bulb receiver of the type 
described, the following additional items are 
necessary to avoid the blot of ostracism: 



dyne, the super-regenerative and reflex sets 
from the standpoint of economy, simplicity, and 
the loudness of signals, the three amiable char- 
acteristics of the defunct criminal, the one-tube 
reflex is the only substitute. It is more than 
a substitute it is an improvement. 

DO NOT THROW AWAY YOUR SINGLE CIRCUIT 
RECEIVER 

TO ACQUIRE the advantages of the reflex 
receiver, it is neither necessary nor desirable 
to discard your present single circuit set. By 
altering a few connections within the receiver 
and building up a small external panel, all quite 
within the ability of our more timid experi- 
menters, the most powerful single circuit os- 
cillator can be converted into a reflex set that is 
a revelation in quality and intensity of signals. 
Fig. i is a photograph of one of the most 
prevalent types of single circuit regenerators 

transformed into the 
reflex. Figs. 2 and 3 
are close-ups of the 
extra panel equip- 
ment that effects the 
conversion. For want 
of a better term, and 
because the same 
auxiliary arrangement 
may be applied to 
any single circuit 
receiver regardless of 
superficial circuit 
variations, the writer 
has named this little 
secondary panel the 
"reflexit." 



One crystal detector (preferably fixed) $1.25 

sth pound No. 22 magnet wire 35 

One length 3 inch cardboard tubing 15 

One .00025 rnfd. variable condenser (Ca). . 3.00 
One audio amplifying transformer (T3). . . . 4.00 

One panel, 5" x 6" .50 

Knob and dial 50 

Incidentals 25 



Total 



$10.00 



8 



Radio Broadcast 



IS YOUR SET ONE OF THESE? 

WE CHOSE for our original demonstration 
the single circuit tuner in most common 
use. The circuit is shown in Fig. 4, and many 
of the trade names under which this system 
parades are divulged in "The Truth About 
Trick Circuits," appearing in the March num- 
ber of RADIO BROADCAST. In addition to the 
hundred of thousands of manufactured sets of 
this type, an incalculable number have been 
built at home by experimenters. 

In the majority of cases, Li and L2 are re- 
spectively primary and secondary of a vario- 
coupler. In the cheaper equipment, Li is the 
stator of a variometer, and La the rotating 
ball. The antenna series condenser (Ci) is 
generally a .0005 mfd. (23 plate) variable. 
The doubtful reader will find the mechanical 
and electrical characteristics of this receiver 
more completely described in the March article 



to which we previously referred. Single tube 
sets of this type sold and, alas! still sell for 
from eight to twenty-five dollars. 

The indicated prices are conservative, and 
on some items the enthusiast will probably be 
able to better them. An ordinary cat-whisker 
crystal stand may, of course, be substituted for 
the fixed element. The latter, however, is 
superior in several ways. It insures the most 
sensitive detection without any adjustment, 
and, due to the low resistance between its 
terminals, eliminates the possibility of oscilla- 
tion and squeals. 

Fig. 5 is the complete wiring diagram the 
rewired single circuit receiver (left) connected 
to the "Reflexit" (right). Our observing 
readers will note that the circuit is identical 
with that of our "Knock-out" reflex, and it 
differs only mechanically in the substitution of 
the variocoupler (Ti) for the usual fixed coup- 
ler. In re-wiring the single circuit tuner, the 




FIG. I 
The "Reflexit" connected to a very common type of single circuit, radiating regenerator 



Reflexing Your Single Circuit Receiver 



only connection that may 
remain intact is the lead 
from the ground to the 
primary of the vario- 
coupler and to the fila- 
ment. 

CONSTRUCTION 

INDUCTANCE T2 is 
1 wound on a 2\ inch 
length of the 3 inch tub- 
ing. The secondary is 
wound first, and consists 
of 51 turns. A layer of 
pasteboard is placed over 
the winding, and the 
primary of 31 turns 
wound on this. 

T3 is any good audio 
frequency amplifying 
transformer with a ratio 
of from four to six to 
one. The Amertran was 
used by the writer. 

The method of mounting and placing of the 
various parts in the "Reflexit" are clearly 
shown in the photographs of Figs. 2 and 3. 
The " Reflexit" may be set and operated in any 
convenient position near the receiver proper. 
The writer found it best disposed of by perma- 
nently mounting it on the cover of the original 




FIG. 2 




FIG. 3 

Another view showing the "works." Note the 
fixed crystal, a "Pyratek" which works well 



A close-up of the "Reflexit." The leads to the re-wired 
single circuit receiver run through the base and cover 



cabinet by a wood-screw through the base. Four 
wires, indicated by the dotted lines in Fig. 5, 
run through the base and cover, and connect 
the "Reflexit" to the rewired single circuit 
tuner. In the combination photographed, the 
four leads are of flexible lamp cord, sufficiently 
long to permit the raising of the cabinet cover. 
They are brought down 
through two holes, the leads 
from T2 and T3 being 
purposely separated to 
obviate the possibility of 
feedback from plate to 
grid circuits. 

Where the original sin- 
gle circuit receiver has 
been built with a generous 
_^^ distribution of free panel 

SBftBHH* space, the experimenter 
may find room for the 
extra control, making it 
possible to incorporate the 
"Reflexit" entirely within 
the old receiver. The Bal- 
lantine Varioformer adapts 
itself very nicely to this 
more compact arrange- 
ment, and a circular 
space, less than two 
.inches in diameter is suf- 
ficient for mounting it. 



10 



Radio Broadcast 




FIG. 4 

The most common type of the single circuit receivers 



\\ hen the Varioformer is used, it is con- 
nected in place of T2 the plate connection 
running to the plate of the tube and con- 
denser C2 is eliminated. The connections 
from the secondary of the Varioformer to the 
crystal and Tj, may be effected without regard 
to lettering or electrical direction. (If a mis- 
take is made, it is compensated for by revers- 
ing the cartridge detector in its clip. This 
experiment should always be made in order to 
secure the correct directional flow of the recti- 
fied current. A difference in signal strength 
with reversed flow may be noticeable only on 
weak signals; the test should therefore be 
made on distant stations.) 

The reader is referred to the Laboratory 
Department of the January RADIO BROADCAST 
for additional data on the use of Mr. Ballan- 
tine's tuned radio frequency amplifying trans- 
former in the one-tube reflex circuit. 

If the reader doesn't care to thread-wind 
the inductances himself there are several 
manufactured coils such as the Workrite, Fada, 
Ansco, and similar transformers designed for 
use with the neutrodyne receivers which may 
be employed. When substituting these com- 
mercial inductances for T"i, it may be neces- 



sary to remove a few turns of wire from the 
primary, reconciling the completed coil to the 
specifications we have given. 

THE SINGLE CIRCUIT TUNER WITH A TWO STEP 

IF YOUR present receiver is a single circuit 
tuner of the type described, plus two stages 
of audio amplification, it can be reflexed with 
similar ease, and with less expense by using 
the last audio transformer as T3. A second 
stage of amplification is seldom necessary with 
the one-tube reflex, nor, due to complications, 
is it desirable. The single tube alone will 
operate a loud speaker satisfactorily on local 
stations, while one extra audio stage gives 
"dancing intensity." Using one step of audio 




FIG. 5 

How to connect the "Reflexit" to the re-wired 
single circuit receiver. The dotted lines indi- 
cate the flexible leads between the two units 



amplification, the output or 'phone leads from 
the reflex are connected to the input either 
to jack or primary of the transformer of the 
first stage. 

OTHER SINGLE CIRCUIT RECEIVERS 

ANY single circuit set may be converted into 
a reflex by the addition of the " Reflexit." 
In the case of slight electrical or mechanical 
variations from the circuit described, such as 
in the "Aeriola Senior," the method of adapt- 
ing the "Reflexit" will immediately suggest 
itself to our more experienced readers. How- 
ever, our less sophisticated enthusiasts, inter- 
ested in the further possibilities of this device 
will find them covered "In The R. B. Lab" 
of coming issues. There will be described, 
each month until the subject is exhausted, the 
manner of adapting the "Reflexit" to the less 
familiar forms of radiating receivers. 




REBECCA HAIGHT 
'Cellist of the Cleveland Institute of Music String Quartet 




The Listeners' Point of 

Conducted b^ 

Jennie Irene Mix 

How Shall We Get Great Artists to Broadcast? 



WHEN and how this much dis- 
cussed question of paying the 
artists who are heard over 
the radio will be settled to 
the satisfaction alike of the 
artists, the public and the broadcast stations, 
it would be futile to forecast. Thus far the 
published discussions of the subject have con- 
veyed three outstanding impressions. First, 
that the public should be given frequent op- 
portunity to hear, through the radio, the most 



famous singers and instrumentalists. Second, 
that all concert artists feel that their profession 
brings them such steady and lucrative returns 
that the radio can be of no benefit to them 
other than the compensation received for 
broadcasting. Third, that this compensation 
should be the same as that which they receive 
when appearing on a concert stage. 

Nowf.or the first point. With the exception of 
New York, and possibly also Chicago, there is 
no city or town in the country that has an 



12 



Radio Broadcast 



average of one concert a week by an artist 
of international fame. 

The accentuation in this country of the fame 
of an artist, depending chiefly on this for his 
drawing power, has done much to retard the 
growth of discriminating musical appreciation 
by deflecting the interest of the public from 
music to the musician. It has also been the 
means of withholding de- 
served success from many 
who, for one reason or an- 
other, have not been able to 
achieve this spectacular 
fame. 

The desire of the directors 
of broadcasting that 
the whole country be 
given opportunity, 
through the radio, to 
hear the great singers 
and instrumentalists 
is deserving of all ad- 
miration. Their mis- 
take lies in thinking 
that concerts of this 
character should be 
given once a week 
and more often if 
possible. In truth, 
if these de luxe pro- 
grams were given 
once a month it 
would mean a mark- 
ed increase in such 
opportunities as 
compared with con- 
ditions that have pre- 
vailed in the past 
and still prevail. 

We come to the 
second point which is 
the most vital of the 
three. Let us begin 
the answer to this by 
a question. 

Of what benefit is it to a concert artist to 
be heard by radio? 

The benefit is so great and so many-sided 
that it cannot be measured to the full. Yet, 
because every man is worthy of his hire, every 
artist who is asked to contribute to a radio 
program should be paid for his services. Any 
other arrangement, when it is a custom, makes 
for the lowering of the relationship between 
the artist and those who ask him to give his 




ALBERT SPALDING 

American Violinist. Mr. Spalding, whose fame has become 
established far beyond the confines of his own country, is 
frequently called, "The aristocrat of the violin," for the reason 
that his playing is always characterized by such classic poise and 
beauty that place him in a class by himself. When he re- 
cently played with the New York Philharmonic orchestra, 
the concert was broadcast and many from distant stations 
later sent word that they had heard Mr. Spalding as clearly 
as if they were in the hall. He is under the management of 
the \Volfsohn Musical Bureau 



services for nothing. The concert-giver's art 
is as much a commercial commodity as are 
any of the necessities or luxuries which we 
daily purchase for the support or embellish- 
ment of our bodies or our surroundings. With 
the exception of performances given for charit- 
able purposes, there is no more reason why the 
musician should be asked to provide entertain- 
ment gratis than why any of us should ask 
the grocers to feed and the clothiers to 
clothe us free of charge. 

But, on the other hand, those of us who 
have been much behind the scenes of the 
concert world do not take seriously the 
assertion that the artist, no matter how 
great he may be, is not benefited by being 
heard by radio audiences. 

The concert artist lives on public patron- 
age, and public patronage can be obtained 
only through advertising. This advertising 
is carried on through two mediums. The 
straight out-and-out advertising which ap- 
pears in newspapers and musical maga- 
zines, and the veiled medium in the form 
of stories which the 
publicity agent con- 
cocts and then per- 
suades editors the 
public will eagerly 
devour. Both of 
these mediums cost 
an incredible amount 
of money. The rea- 
son why so many 
fine artists have 
passed into the ob- 
scurity of the teach- 
ing profession is be- 
cause they have not 
had the money to 
keep up this adver- 
tising. Their names 
must be constantly 
before the public if 
they are to succeed. 

And even after success has come, the advertis- 
ing must be kept up with equal vigor, or they 
drop to the rear of the procession, then soon are 
out entirely. 

We grant that every rule has its exceptions. 
There are at present two artists in the concert 
field a man and a womanwho, such is their 
immense popularity, never have to do any 
general advertising other than that which 
gives notice of a coming concert. Who are 



The Listener's Point of View 



they? It should be necessary only to say 
that one is a violinist, the other an erstwhile 
prima donna. But, mark you, in past years 
they spent large sums for all kinds of pub- 
licity. 

If he is not advertised the artist has no 
chance to be heard. And many, even if ad- 
vertised, still have little or no chance. It is 
not uncommon for thousands of dollars (the 
artist's dollars) to be spent in attempts to get 
him before the public, but without success. 
The workings of the concert world behind the 
scenes are so intricate, so many factors enter 
into the success or the failure of every booking 
even of the long-established artists, that for 
those less known the profession brings but a 
hand-to-mouth existence. 

To such as these the radio should prove of 
incalculable value. Through its means they 
can be heard not only by the general public, 

MOR1Z ROSENTHAL 

Polish Pianist. For more than forty years Moriz 
Rosenthal has been a dominating figure in the musical 
world. He first toured this country when he was little 
more than a youth. His second tour was in 1896-7. 
And now, at the age of sixty-two, and after an absence 
of seventeen years, he is again being heard here. His 
initial New York recital, given soon after he arrived, was 
broadcast through the cooperation of the Radio Corpora- 
tion of America, and reports received from his managers, 
the Wolfsohn Musical Bureau, tell of gratifying results 





ALPHONSE GUYON 

A young pianist whose recitals have a number of times 
been broadcast by the Westinghouse Station, WBZ, at 
Springfield, Mass. Mr. Guyon's work will bear watching 
by those who are looking for fresh talent admirably 
trained. His programs are always of high standard, and 
his playing, especially of works from the romantic school, 
intelligent and imaginative 

but, what is even more important, by concert 
managers throughout the country. 

The day has gone by when concert managers 
engage artists on the excerpts of criticisms of 
the artist's appearance in New York City. 
This, because such excerpts are only from the 
laudatory portions of the criticisms, and be- 
because too many times has it happened that 
the singer or player has failed to measure up 
to the exacting standards obtaining in what the 
effete East so condescendingly refers to as 
"the provinces." In the past, managers have 
lost so much money in promoting musical at- 
tractions on New York prestige, or what seems 
to be such from the critical excerpts, that they 
have grown wary. They must hear to believe. 
Not being able to hear, they strike the artist's 
name from their contemplated list of attrac- 
tions. 

But suppose they could listen in to these 



'4 



Radio Broadcast 



New York concerts, or could hear the artists 
sing or play a group on a regular radio program. 
This would go a long way toward solving the 
problem for the artist and the manager. Mu- 
sic, to be sure, does not always broadcast suf- 
ficiently well to give the hearer a just basis 
from which to judge the performer. But it 
does so often enough to make this means of 
communication between the artist 
and the manager worth the trying. 
There are certain fundamental quali- 
ties that every artist must reveal, and 
when the numbers broadcast are well 
known to the listener these qualities 
can in many instances be discerned. 
The tempo carries with fi- 
delity; the phrasing can be 
followed; also the propor- 
tion with which the entire 
number is made a well bal- 
anced whole. And, miracle 
of miracles! the radio brings 
out with amazing effect the 
feeling with which a work is 
interpreted. The perform- 
ance of a number over the 
radio that is characterized 
by consistent tempi, intelli- 
gent phrasing, the adjust- 
ment of each part so that it 
makes a well proportioned 
whole, and an understand- 
ing of the emotional con- 
tent, brings assurance that 
the singer or player has the 
qualities of an artist. 

Why then, if he can get 
into touch with concert 
managers through the radio, 
should such an artist be paid for his perform- 
ance? 

For the simple reason that even while he is 
benefiting himself he is giving pleasure to un- 
told numbers of listeners and thereby helping 
to make this particular program a desirable one. 

So all-powerful is this matter of publicity in 
the musical world that it would be well for 
artists and their managers if every worth-while 
program given in New York were broadcast. 
The mechanical devices that have made 
possible the hearing of artists through their 
records, are what has made the success of 
these artists when touring the country. This 
has been proved beyond all question. The 
artist who has never made records cannot com- 



pete with those who have. This fact destroys 
the argument that if people hear an artist 
over the radio they will not trouble to go and 
hear him in concert. They will not only want 
to hear him in concert when the opportunity 
presents itself, but they will go the most 
readily to the program that contains some of 
the numbers they have heard by radio. 

Perhaps, at first, some people will 
stay at home and listen in if, when 
the artist comes to town, his pro- 
gram is broadcast. But, ultimately, 
unless human nature changes in the 
meantime, the broadcasting of pro- 
grams of an artist on tour will 
have little if any effect on 
the attendance at con- 
certs. There was the 
same pan- 
ic among 
themana- 




WILLIAM MENZER 
At work with his musical saw. On sev- 
eral occasions the peculiar harmony from 
this remarkable instrument has been 
broadcast from WJZ, New York 



gers when records became 
so universal. People would 
stay at home to hear, John 
McCormack, let us say, 
through his Victrola rec- 
ords, rather than paying to 
hear the same numbers in 
the concert hall. But they 
did nothing of the kind. On 
the contrary it was because they had his rec- 
ords that they went to hear him. They 
wanted to be right there on the spot to look at 
him while he sang. 

And now to the third and last point: The 
amount that should be paid the artist for 
broadcasting. 

The general impression seems to be that the 
remuneration for a radio performance should 
be the same as that received on tour. The 
truth is that one-half of this remuneration 
should be sufficient to leave the artist as large 
if not a larger profit than he makes in his 
regular concert work. Much has been said 
about the big sums earned by concert artists. 
But note what has to be paid out by them. 



The Listener's Point of View 



The traveling expenses for the artist, and, 
unless he is a pianist, the accompanists' fee 
and also his traveling expenses with the excep- 
tion of his hotel bills; the manager's commis- 
sion; advertising and publicity; the practice 
hours with the accompanist preliminary to the 
tour; dress proper for every occasion, morning, 
afternoon, or evening concert, and always up 
to date and immaculate. The waits between 
engagements when the hotels make inroads on 
the fee. And the many small expenses that 
in the aggregate bring the fee down still more. 

All of these expenses are taken into con- 
sideration when the artist's fee is fixed. But 
it is a question whether the same fee should 
be required for a radio performance which 
would entail no expense on the artist except 
his manager's perfectly justifiable commission 
and, when necessary, his own accompanist. 
This is a point to which broadcast directors 
would do well to give con- 
sideration. 

As for the aspirants for 
concert careers who are still 
in the non-professional 
class, they should not be 
paid anything for broad- 
casting. These radio oppor- 
tunities should be looked 
upon by them as debuts. 
If they go to New York to 
make a debut (as hundreds 
of them do) it costs them, 
entirely aside from their 
personal expenses, any- 
where from $600 to $1,000 
for the one concert. Not a 
dollar comes in at the box 
office to help out, because 
the houses are always pa- 
pered for these debuts. 
Why, then, should they ex- 
pect to be paid if they make 
a debut via radio? To be 
quite frank, the truth is 
they should not be heard at 
all through this medium 
until their work has been 
approved by a competent 
committee of judges. 

Music in its relation to 
the radio is a problem that 
many directors of broad- 
casting are earnestly striv- 
ing to solve. The right 



solution can come only through a thorough 
knowledge of the musical conditions existing in 
the concert field as well as in the field of radio. 

"Humoresque" and the "Suwanee River" 

ONE of the most popular instrumental 
numbers with radio listeners is Dvor- 
ak's charming, " Humoresque." But 
perhaps few who hear it know that the theme is 
taken bodily from "Suwanee River." You can 
easily prove this by playing the " Humoresque" 
while at the samtTtTrne singing the song. In 
the days when Alma Cluck and Efrem Zim- 
balist used to tour together one of their most 
popular encore numbers was the singing by 
Cluck of "Suwanee River" to the accom- 
paniment of "Humoresque" played by Zim- 
balist on his violin. The combination was 
not, as many supposed, a discovery of theirs. 




RUTH WILLIAN 
Second violin of the Cleveland Institute of Music String Quartet 



i6 



Radio Broadcast 



1 1 has long been known to musicians. Dvorak, 
from 1892 to 1895, was director of the National 
Conservatory of Music in New York, and 
during that time became much interested in 
the melodic character of plantation music. 
He made use of these melodies 
in his "Symphony from the 
New World" although in mood 
the symphony bears the flavor 
of his native Bohemia, and is 
not, as some would have us be- 
lieve, intended to be representa- 
tive of America. And although 
he used "Suwanee River" 
as the theme of " Humor- 
esque" this composition, 
too, is Bohemian in spirit. 
If Dvorak were living 
and could get a royalty on 
every radio performance of 
' ' Suwanee- Humoresque 
he would be a plutocrat 
among composers. 

When Singers Broadcast 

HERE'S a bit of ad- 
vice for singers 
who broadcast. 

Don't drag the tempo! 

Contraltos in particular are 
apt to slow down the tempo 
until they get on the listener's 
nerves. They are inclined to do 
this on the concert stage, which 
is bad enough, but when it 
comes to the radio the habit 
becomes distressing. Nor are 
sopranos and tenors wholly ex- 
empt from this criticism, but for 
some reason the baritones 
nearly always keep the tempo 
up to normal. 

When a singer drags through 
a phrase, it means a gasp for 
breath at the end of it. This 
gasp is even more apparent 
over the radio than in the con- 
cert hall. 

The radio microphone is an ex- 
traordinarily faithful reproducer of every sound, 
a fact which artists may slight and it will be 
well for singers to remember this when broad- 
casting if they want to make a good impression 
on their listeners, which, of course, they all do. 



T; 



HE Wolfsohn Musical Bureau goes on 
record as one of the first organizations 
among the musical managers to broadcast not 
only the New York concerts given by their 
artists but also those presented on tour. At a 
time when musicians and managers are 
uncertain of the answer to the question 
"to broadcast or not to broadcast," this 
action is decidedly interesting. 

To this management also goes the 





tinent. 

Mario 

leading 

politan 

Cecilia 



CECILIA HANSEN 
Russian violinist. One of the 
artists under the management of 
the Wolfsohn Musical Bureau 
who broadcast from the Waldorf 
Hotel at the Massachusetts In- 
stitute of Technology alumni din- 
ner on March 7, 1924. WJZ, 
WGY.KDKA, KFKX, KGO.and 
2AC (Manchester) broadcast her 
playing. On the same program 
was Mario Chamlee, one of the 
leading tenors of the Metropoli- 
tan Opera Company. One esti- 
mate has it that an area of one 
million square miles was covered 
in this wholesale broadcasting 
experiment 



credit of being the 
first to have a con- 
cert broadcast 
t h roughout the 
country by relaying 
it through four sta- 
tions across the con- 
This was done when 
Chamlee, one of the 
tenors of the Metro- 
Opera Company, and 
Hansen, Russian vio- 
linist, recently gave a program 
at the Waldorf Astoria, New 
York. Through the cooperation 
of the Radio Corporation of 
America, Westinghouse and 
General Electric Companies, 
this concert was broadcast from 
Station WJZ, New York, picked 
up to be rebroadcast by WGY, 
Schenectady; KDKA, Pitts- 
burgh; KFKX, Hastings, Ne- 
braska; and at 10:30 p. M. New 
York time, station KGO at 
Oakland, California, and station 
2AC of the Metropolitan-Vick- 
ers Company at Manchester, 
England. Various estimates of 
the amount of territory covered 
by this quite revolutionary 
"blanketing" broadcasting have 
been made, the most striking 
perhaps being that one million 
square miles of the earth were reached. Among 
others under this management whose concerts 
have been heard by radio are Moriz Rosenthal, 
Albert Spalding, Manuel Quiroga, Mabel Garri- 
son, and the New York String Quartet. 



The Listener's Point of View 



As If From Heaven 

A'Y ONE who has not listened over the 
radio to the choir of St. Paul's Episco- 
pal Church in Detroit should do so at 
the next opportunity that presents itself. Who- 
ever is the organist 
there knows, as do few 
church organists, how 
to eliminate the usual 
deadly monotony of 
church singing. The 
numbers that should 
go with spirit go with 
such unflagging life 
that the only word by 
which to describe the 
effect is the hack- 
neyed, " Inspiring." 

Not long ago they 
sang, evidently as the 
recessional, "Onward 
Christian Soldiers," 
It came through the 
ether like a thunder- 
ous yet bright clarion 
call to action. 

They sang every 
verse. A group of us 
listened in silence, the 
effect being all the 
greater because the 
singers could not be 
seen. At the close 
one in the group said, 
" But it didn't sound 
at all like church sing- 
ing." To which a young man, not conspicuous 
for his interest in church matters, replied, in 
awed tone: 

"No. It sounded like the Heavenly Host." 

IT IS becoming quite the thing for radio sta- 
tions to give occasional programs made up 
wholly of songs that were the popular songs 
of the day, thirty, forty, fifty or more years ago. 
WOAW at Omaha, Nebraska, has presented 




ANDRE DE REBAUPIERRE 

First violin of the Cleveland In- 
stitute of Music String Quartet 



a number of such programs. A delightful 
custom and one that should continue. What 
reminiscences these songs must bring up to 
those who were young when they were the 
vogue. It would be a good thing if some of 
them could be permanently revived. There's 
romance in them and 
gayety as well hu- 
mor, too. No doubt, 
when broadcast, they 
set many a grand- 
father and grand- 
mother telling of the 
good times they had 
when they were young. 

ALTHOUGH, in 
age, this depart- 
ment is only in its 
second month, a num- 
ber of inquiries from 
readers have been re- 
ceived along the line 
of Won't you please 
write something about 
this? or What do you 
think of that? and so 
on and so on. 

Which leads to the 
statement that the 
conductor of this de- 
partment will always 
be glad to receive 
opinions, whether crit- 
ical or otherwise, of 
whatever may be said 
in the department ; 

also suggestions as to what ought to be said 
for the good of all concerned. 

An editor's opinion, although drawn, as it 
always should be, from long and practical ex- 
perience along the lines discussed, is yet but 
an individual opinion. And as we should all, 
no matter how firm our convictions on any 
subject, be ready to hear the other side, this 
department will ever be open to progressive 
criticisms or constructive ideas. 





THE RADIO ANTENNAS ON A DREADNAUGHT 

The illustration shows the antennas on the U. S. S. Colorado. The long cage antenna is used for the 
large arc transmitter. The other antennas are used for spark and radio telephone communication 



The March of Radio 

Is the Problem Solved? 



S3 MANY times we have asked the 
question "Who is going to pay" 
that any reasonable attempt at the 
solution of the question of the cost of 
broadcasting is very welcome and will 
be watched by millions of listeners with a great 
deal of interest. In the very first issue of 
RADIO BROADCAST an attempt to analyze the 
possible solutions of this problem was made. 
One of the possibilities suggested then was 
that of soliciting contributions from the radio 
audience, a scheme the Church has depended 
upon heavily for many years. It is not at all 
evident however that the radio broadcast 
managers would be as successful in this method 
of getting funds as are the ministers of the 



gospel; neither the hope of Heaven nor the fear 
of Hell will act as brother conspirator with the 
station manager to pry loose some of the sav- 
ings of their audience. It seemed possible 
even two years ago, that the public would re- 
spond to an appeal for funds in an unexpected 
degree, and the possibility is even more im- 
minent to-day after the remarkable demonstra- 
tions of the way in which radio broadcasting, 
properly supported, can instruct and amuse its 
millions of listeners. 

With this idea in mind a committee of New 
York business men has been formed to try out 
this scheme of broadcast financing. It seems 
evident that a station itself could not very 
well carry out such a scheme because a large 



The March of Radio 



part of the public would imagine that their 
contributions were going to pay dividends for 
the stockholders of the company rather than 
for putting out good programs. One or two 
rumors to this effect would kill completely any 
scheme managed and controlled by a business 
concern such as the Radio Corporation or the 
American Telephone and Telegraph Company. 
To convince the public that a bona fide 
attempt was being made to give them self- 
supporting radio, the committee which has 
undertaken the task of introducing this in- 
novation has been wisely made up of prom- 
inent financiers, who could not possibly be 
suspected of any idea of profit-taking, and who 
have been intimately connected with many 
other musical ventures. They are men whose 
names will at once command the respect and 
confidence of the prospective contributors. 
This committee has solicited funds from the 
radio public, calling for contributions of from a 
dollar up, from all those who are entertained 
by WEAF, through which the new broadcast- 
ing programs are to be sent. This station has 
been selected, it is said, because of the "excel- 
lent quality of its modulation and transmis- 
sion." All of the funds received from the radio 
listeners will be directly applied to the securing 
of artists of the highest caliber. The com- 
mittee will serve voluntarily, and the station, 
WEAF, has agreed to carry out the programs 
free of charge. This is no small contribution 
on the part of the American Telephone and 
Telegraph Company in view of the fact that 
this station commands a fee of $400 per hour 
for its use for advertising. 

There have been favorable comments made 
about the scheme, and some adverse and dis- 
couraging. The manager of a well known sta- 
tion expresses the opinion that the public will 
not contribute to any extent for a form of 
amusement which they have a fair chance of 
getting without paying for it. For he says 
the letters he has received from his listeners 
recently seem to show a spirit of dissatisfaction 
with what they are getting already, rather than 
a willingness to part with some of their good 
money to help the distraught manager in 
scheduling more interesting events. 

The price paid for a good receiving set to-day 
is high, and any business man who looks inside 
his $150 or $200 set naturally wonders why he 
has to pay so much for a few coils, condensers, 
tube sockets and the like. Feeling that he 
actually got about $50 worth of apparatus in 




Underwood & Underwood 
THE MOST IMPORTANT CLOCK IN THE WORLD 

Is this chronometer at the Royal Observatory, at Green- 
wich, England, the starting point of longitude in the 
world's maps. Signals from this clock are now sent out 
daily from all nine stations of the British Broadcasting 
Company 



20 



Radio Broadcast 



his purchase he expects to realize on the other 
$100 from the enjoyment of radio programs 
for which he will not have to pay anything. 
Hence when these fail to please he uncon- 
sciously feels that he has, perhaps, been "done" 
and hence his letter of discontent to the station 
manager. 

Another objection to this proposed scheme 
of broadcast financing naturally comes from 
those stations which will not secure the service 
of these well paid artists. "It looks all right 
for WEAF," says one manager, "but how 
about the other 534 stations in the United 
States?" This bares a very important point 
in the broadcasting situation: are all these 
stations entitled to a share of any fund 
collected from the radio audience at large? 
Many of them seem to think so, but there is 
really no justification at all for their stand. 



How many of us would contribute money to 
hear a program from a poorly managed, poorly 
equipped station, such as many of them are 
to-day? If these stations put out such a re- 
quest as has emanated from WEAF it is un- 
likely that one dollar would be contributed. 
There are too many stations to-day which feel 
they have a right to be on the air irrespective 
of what kind of material they send out. They 
appear to forget that the ether is the public's 
and they are on the air not by right but by- 
tacit permission. And the public certainly has 
a right to send its money in to that station from 
which it can get the highest return. 

Just as every good music lover cannot help 
but wish success to the Metropolitan Opera, 
even though this company gets a disproportion- 
ately large share of the public's opera money, 
just so we hope this new scheme will meet with 




PRESIDENT COOLIDGE 

CaJmly before the calm microphone in a recent radio address. The President has three times lately made use of radio 
to reach great numbers of his fellow countrymen. So can the strength of the Chief Executive be saved. As the most 
prominent Republican candidate for the Presidential nomination in June, 1924, he may be heard quite frequently by the 

nation's radio listeners 



The March of Radio 



extraordinary success. Even so, it must not be 
regarded as a final solution to the problem. 
We expect that it will serve merely as a trust- 
worthy indication of the public's real desire in 
broadcasting. And it is the good of the general 
listener, not that of any station or company, 
which must be of chief importance in deter- 
mining the method of solving the problem. 

Where Radio Broadcast Stands 

PERHAPS no article ever published in 
any radio magazine has created as 
much comment as Zeh Bouck's "The 
Truth About Trick Circuits." The avalanche 
of letters reaching us expressing various opin- 
ions indicates just how badly an expression of 
honest belief has been needed. 

For the most part the letters we have re- 
ceived indicate that we gave expression to 
thought hiding in many minds. There have 
been a few objections from our friends in the 
industry. And we say "friends" advisedly. 
Let us explain: 

Among the circuits treated in a most caustic 
manner was the Flewelling adaptation of the 
super-regenerative receiver. During the radio 
show and convention held in New York we had 
the pleasure of meeting Mr. Flewelling. 

Amid the din of a few dozen loud speakers, all 
vying with each other for supremacy, Mr. 
Flewelling, Dr. G. W. Pickard, inventor, Zeh 
Bouck, and the editor sat together on a large 
table where admission tickets were being sold. 
We went right to bat, laid all our cards on the 
table and we are glad to chronicle the results 
here. Doctor Pickard appeared to be very 
sure that super-regeneration is accomplished by 
the Flewelling circuit. That may be, but our 
criticism was of a different nature. Our 
principal complaint was that the circuit, in the 
form in which it received so much publicity 
about a year ago, is a malignant squealer. 

Mr. Flewelling paid us a real compliment by 
saying: "1 have been panned many times be- 
fore; but when RADIO BROADCAST took its 
crack at me it hit me in a tender spot. You 
fellows, by ; inference, intimated that I was 
party to the the unloading of "gyp" merchan- 
dise 'and the truth of the matter is that I was 
made some very flattering offers if I would place 
my approval on all kinds of units which could 
be used in my circuit. I refused them all." 

Such a construction is possible from the 
article as we published it, but it was entirely 




SENATOR ,HIRAM JOHNSON 

At home before a receiving set. As another Presidential 

candidate, his voice may also soon be heard by radio 

listeners who have a bent toward politics 

unintentional, and Mr. Flewelling could not pre- 
vent the exploitation of his own circuit by cer- 
tain irresponsible agencies. Mr. Bouck aptly 
says he has been more sinned against than 
sinning. 

Another gentleman a prominent manufac- 
turer of parts and sets, invited us to his office 
and proceeded with a rather fervent roasting. 
His most important criticism was that the tone 
of Mr. Bouck's article was not of the harmonious 
nature that would create interest in home-built 
receivers from standard parts. This particular 
.gentleman's days are very crowded and he does 
not have as much time as he would like for the 
perusal of magazines. He was unfamiliar with 
the how-to-make-it articles we publish each 
month after we have actual working samples 
of the devices described. 

We are firmly convinced that by keeping our 
faith with our readers we are serving the entire 
art. It is far from our policy to suggest a 
reduction in the number of home-built sets. 
That business, in our opinion, will always 
thrive. However, we also believe that ex- 
aggerated claims for this, that or the other 
circuit, will, after Mr. Home-Builder has been 
sadly disappointed a few times, make him 
doubt the legitimate claims made for eve,n 
really good circuits and honest products. We 
hope this will correct any similar impression 
others among our readers have entertained. 

Another manufacturer and strangely enough 
another maker of parts (in an unsolicited letter), 
says, in part: 

. . . I was particularly impressed with the 
article by Mr. Zeh Bouck in the March issue of 
RADIO BROADCAST which clarifies to the public the 



Radio Broadcast 




ONE OF THE YOUNGEST RADIO FANS 

Is Miss Arline Weber of Chicago. She apparently 
has no complaint to offer on the incoming program 



question of "trick circuits." This has been one of 
the bad features of the business. It plays on the 
psychology of public curiosity and 1 think it may 
help to sell a lot of merchandise which will certainly 
put the good merchandise to the fore in time. The 
cause has turned the American public into a nation 
of experimenters who are going to register their 
opinion in time in no uncertain manner. 

It is my personal opinion and the opinion of our 
company that the solution of better reception is not 
going to be in "trick circuits" or in various frills 
which will be added to the circuits, but the solution 
will be in the refinement, both mechanically and 
electrically, of the material with which we must 
work. We are, therefore, experimenting constantly 
until we find both the mechanical and electrical 
properties of our product to be good. . . . 

The writer.who has been twenty-one years in the 
radio business and during that time watched its 
progress both actively and in a purely observing 
capacity believes that this will be the ultimate 
goal for which any legitimate manufacturer must 
strive. 



industry has, as yet, put in 
its appearance. On the 
other hand there are many 
a great many of the char- 
acter we are pleased to 
record below. As most of 
our older readers will re- 
member, most of the sug- 
gestions in this good letter 
from a student at Massa- 
chusetts Institute of Tech- 
nology^ have already been 
given attention. In many 
instances, other periodicals 
have campaigned against 
squealing receivers. 

Editor, RADIO BROADCAST. 
DEAR SIR: 

I was very much pleased 
at Mr. Zeh Bouck's article on 
"Trick Circuits." You and he 
invited about twenty libel 
suits, and I admire your cour- 
age. You are the first to come 
out flatly, give names, and be 
specific. I know a few "fat- 
head" B. C. L.'s who believe 
everything they see in print. 
I hope they accept your article 
the same way. 

You might razz Mr. Kauf- 
man some more. His first 
circuit was, as you called it, the "goulash." He 
brought out another, using the reversed feedback 
also a transmitting circuit. He called it the Kauf- 
man No. 2. And I think there are thousands 
ruining the ether. The ultra-audion is another. 

Here I am living fifty minutes from a nest of 
iniquity, at the Riverbank Court Hotel. There are at 
least 20 aerials on that roof. I tried to stem the tide 
of radiation. In my first interview I met a very 
well-to-do director. He thought me a fanatic! 
He had a Grebe "g" and listening in to his tuning 
was painful. He knew nothing whatever of the 
subject, nor his receiver, nor radio. He blamed the 
howls, squeals, etc., on the amateurs. What can you 
do with such a person? I gave up the task in disgust. 
The richer and more able to afford a non-radiating 
receiver, the dumber they are. The dumb owners 
of Colpitts oscillators, alias flivver circuits, are a 
great menace here in New England. 

If you want to do a great service, describe only 
non-radiating receivers and get fellow editors to do 
the same. 



This other request takes a lot of my nerve. It is a 

It is significant to note that not a single lot to even talk about. A good way to check radi- 
ation would be to have an issue in as many maga- 



criticism from readers not associated with the 



The March of Radio 



zines as possible devoted entirely to factory made 
and other receivers, taking each class of "pest" list- 
ing all known factory makes of that type, also aliases, 
and tell how to convert them into good sets. Give 
good notice to the Sodion tube and how to convert a 
single circuit into a good receiver, using this tube and 
without need of much extra parts except a potentio- 
meter. Make it detailed for the "dumb-bells." 
By mentioning radiating makes of receivers specifi- 
cally you are in little danger of a libel suit, for 
radiation can be easily proved, and the truth is a 
perfect defense for you. 

I am an experimenter, and my interest in the music 
is little, with the exception of some very good music 
from good stations. Hence I am not a novice. But 
I would like a clean air to test in. Interference 
can be avoided by a good set, but the best types of 
receivers are helpless before radiating receivers. 
Yours truly, 

C. J. LeBel 

Expensive Service 

PRESIDENT COOLIDGE'S speech on 
Washington's birthday was not broad- 
cast from a Chicago station, as it had 
been announced, because the station's manager 
thought the service cost too much to make it 
worth-while. Any broadcasting of this kind 
is entirely dependent upon the American 
Telephone and Telegraph Company who con- 
trol all of the long distance telephone lines of 
the country. Unless their cooperation is 
secured, practically no broadcasting can be 
done from points outside the studio. Thus all 
of the ambitious broadcasting stations, desiring 
to put on the air affairs which take place at 
distant points, are entirely dependent on the 
country's great communication company. 

The Westinghouse engineers, with their short 
wave transmission from Pittsburg to Nebraska 
have solved, to a certain extent, the question 
of remote modulator control but, of course, 
the Chicago station could not very well set up a 
short wave transmitter at the White House, to 
relay the speech to Chicago. The General 
Electric Company has used a small portable 
short wave transmitter to actuate WGY from 
points a few miles away. Such a scheme is 
possible, but not yet as desirable as a good 
telephone line connection. 

So the question arose how much should a 
broadcasting station be charged for the use of a 
long distance line for a few minutes when the 
President is speaking? Apparently $1000 was 
offered but the "asked" price did not get 
below $2,500, so a sale was not made. In the 



words of the discomfited radio station mana- 
ger "the regular long distance charges for the 
use of wires from Chicago to Washington is 
only $4.80 for the first three minutes and 
$i .60 for each additional minute. The original 
plan was for the President to talk ten minutes; 
at the regular rates the cost of the wires would 
then be $14.80. Because of the necessity of 
having well balanced wires and other possible 
special care, one Chicago station offered the 
American Telephone and Telegraph Company 
$1000 for the servkejrom Washington, but 
even at that figure the service was refused." 

Before condemning the telephone company 
for its apparently excessive charge for this ser- 
vice it must be considered that the ordinary 
wire connection will not serve at all for such a 
purpose. Special lines and repeaters have to 
be taken out of regular service, have to be put 
through special tests and adjustments, all 
extraneous "noises" eliminated and a special 




HOW KDKA WAS RE-TRANSMITTED IN ENGLAND 

The receiving set had six stages of tuned radio-frequency 
amplification, detector and two stages of audio-frequency 
amplification. This special station is installed at Biggin 
Hill, near Manchester. In the photograph are, left to 
right Mr. Honri, of the British Broadcasting Company, 
Mr. Webb, of Popular tireless, and Captain West, Assist- 
ant Chief Engineer 



Radio Broadcast 



staff of men, as well as spare lines, be kept in 
readiness in case the connection should fail. 
However large we may think the bid of 
$2,500 for ten minutes' service may be, all of 
the related factors are not on the surface, and 
we feel that the Telephone Company is entitled 
to the benefit of any doubt there may be, 
when w r e consider the fine radio broadcast ser- 
vice they have given the public during the 
past year. Whatever may be the policy of 
their financial advisors, we do know the 
company makes a continual effort to improve 
broadcasting service. This has been of great 
benefit to the radio public a public which 
so far has paid the Telephone Company noth- 
ing at all for the service. It is well to remem- 
ber also that the radio receipts of the Ameri- 
can Telephone and Telegraph Company are 
practically nothing at all whereas an organiza- 
tion like the Radio Corporation has an income 
from the radio public which must be measured 
annually in the tens of millions of dollars. 

Good Work by the Bureau Physicists 

A FEW of the workers in the field of radio 
development have received rich ma- 
terial rewards for the successful solu- 
tions of certain radio problems. We think at 




DR. J. H. DELLINGER 

Of the Bureau of Standards with the standard wave- 
meter at the Bureau laboratory in Washington 



once of Armstrong, Pupin, Hazeltine, and 
others. Other workers spending months and 
years upon the solution of problems of great 
importance in the advancement of science, in 
the saving of lives, prevention of shipwrecks, 
etc, receive practically no direct financial 
reward when their work is successfully com- 
pleted. Among such workers must be reckoned 
most of the research workers in University 
laboratories and certainly those on the staffs 
of such institutions as the Bureau of Standards. 
Much valuable work is done by the physi- 
cists of the Bureau. This is the kind of work 
that practically never brings much remunera- 
tion to the worker. Tests on the applicability 
of short waves for radio transmission were 
carried out at the Bureau quite some time ago. 
This work is and has been of great value to such 
companies as the \Vestinghouse which, of 
course, gets credit from its radio audience for 
putting into operation the remarkable short 
wave channel from Pittsburg to Hastings, 
Nebraska. This work of the Westinghouse 
engineers naturally deserves much approba- 
tion, and it does get it, whereas the work of the 
Bureau scientists remains unknown except 
to a few who happen to consult the bulletins 
describing the work of the Bureau. 

There has recently been published by the 
Bureau, Scientific Paper No. 480, 
describing a new type of radio bea- 
con station, and its use in the navi- 
gation of aeroplanes. Ordinarily an 
aeroplane is guided to its port by 
the use of a directional radio re- 
ceiver mounted on the plane itself; 
generally two coils at right angles, 
the scheme attributed to Bellini- 
Tosi, is employed. It is by no 
means easy to carry on accurate 
directional measurements on a noisy 
aeroplane, going at its tremendous 
speed. The Bureau workers set out 
to find a more easily manipulated 
scheme for the plane's pilot. 

This pamphlet gives the results 
of a series of experiments made 
with the view of not requiring di- 
rectional measurements on the plane 
itself. All the operator on the 
plane had to do was observe the 
signal intensity. The sending sta- 
tion uses two large coil antennas, 
mounted about 135 degrees apart. 
On the plane, a simple non- 



The March of Radio 



directional receiving set suffices. Signals are 
transmitted alternately from the two coils 
at the transmitting station. On a line divid- 
ing the 135 degree angle the two signals 
will be received by the pilot with equal 
strength, but in other directions the signals 
from the two coils will be of unequal strength. 
After the radiation from this beacon is once 
picked up, the pilot maneuvres his plane until 
the two signals are of equal strength and then 
holds to the line in which this equality is main- 
tained, and he will be making a straight course 
for the station. 

Tests carried out with the assistance of the 
Army air pilots seem to indicate that this new 
type of radio beacon will much facilitate the 
accurate navigation of air craft, at night or 
under bad weather conditions, when ordinary 
observational methods fail. The develop- 
ment of this new radio beacon was carried out 
by Messrs. Dunmore and Engel, physicists of 
the Bureau of Standards. 

"Fifty Million People Hear General Carty 
Speak" 

SO ONE staid New York newspaper an- 
nounced recently. Off hand, we thought 
they had slipped in one too many zeros 
in the linotype, but these same fabulous figures 
appeared the next day in even more positive 
form. This statement is quite in line with 
other confident assertions of what radio is do- 
ing. This newspaper in question should send 
its radio editor to an elementary class in radio 
principles, and then to some other necessary 
one in which gullible souls are taught to dis- 
tinguish between solid facts and idle dreams. 

The occasion which called forth this ridicul- 
ous statement was a most remarkable one; no 
foolish exaggeration was necessary to make 
possible the wording of an attractive headline. 
General Carty, vice-president of the American 
Telephone and Telegraph Company, was giving 
a speech to a group of business men in Chicago, 
and as is usual on such an occasion, he spoke on 
the significance of communication to the 
prosperity of a people, and especially on the 
past and future developments in the commun- 
ication art as it exist in America. After point- 
ing out that radio and wire were not in conflict, 
but rather supplement one another, this well 
known telephone engineer gave a most re- 
markable demonstration of the communication 
facilities his company had brought into being. 




BETTY BALFOUR 

A well-known and popular British "cin- 
ema" star before the microphone at 2 LO 

Speaking into the microphone at the banquet 
hall in Chicago, General Carty's 'voice was 
carried over the company's transcontinental 
line, from San Francisco to Cuba (the step 
from Key West to Cuba was by means of 
specially constructed submarine cable). Oper- 
ated by the voice currents as they traveled east 
and west from Chicago over this line, were six 
radio broadcasting stations: Havana,' Washing- 
ton, New York, Providence, Chicago, and San 
Francisco. This tremendous spread of ether 
waves was accurately controlled by the less than 
one millionth of one watt of sound which was 
absorbed by the microphone in Chicago. 
There is a picture for you. 

The manager of WEAF has estimated his 
average radio audience at 500,000 with a possi- 
ble maximum of three million. This was the 
most powerful station of the six taking part in 
the demonstration, and, being situated in the 
most densely populated part of the United 
States, a reasonable estimate of the number of 
people who heard General Carty speak would 
be five million, at the outside. Every one of 
these five million must have had his imagina- 
tion kindled and his admiration of the technical 
genius of his country enhanced, when, settled in 
the comfort of his home he heard the speaker 
say "Hello, Cuba" and the immediate response 
from Havana, and then a few seconds- later 
" Hello, San Francisco," and immediately back 
"Hello, General Carty, this is San Francisco 
talking." - 

It is a pity that Alexander Graham Bell's 
death came too soon for him to hear this 
demonstration of the growth of the art his 



26 



Radio Broadcast 




SUPER-HETERODYNES 



And Major Edwin H. Armstrong, the originator of the super-heterodyne circuit. The cabinet on the left is his original 

"super," and the cabinet behind it is the working model for the finished commercial product on the right. Mr. H. W. 

Houck, who aided Major Armstrong in the development of the set is standing on the left 



simple experiments started. He would have 
heard one man speak to millions, scattered over 
the length and breadth of our land. Even 
knowing the step by step progress by which 
this accomplishment has been made possible, 
it was with difficulty that we kept back the 
sentiment of that other message so important in 
the history of communications development: 
"What hath God wrought." We would also 
add, What great credit is due to those hundreds 
and thousands of bright, earnest, young en- 
gineers, whose diligent efforts and keen appli- 
cation make possible this almost unbelievable 



progress ! 



Radio in Great Britain 



TWO recent news items on the radio 
situation in Great Britain deal with 
the Government's control of the radio 
field in that country. As we know, control of 
the broadcasting has been closely guarded in 
England. The Postmaster-General is the man 
whose decisions completely regulate the com- 
mercial broadcasters. He it is who tells mil- 
lions of listeners what kind of receiving ap- 
paratus they may use. As related in these 
columns some time ago, it is illegal in the 



British Isles to use a receiving set which can 
radiate an appreciable amount of power, a 
regulation which, if put into effect in our 
country, would rule out millions of sets. In- 
cidentally we learn of several new stations 
being put up in England and Ireland. It must 
be that most of the listeners use crystal sets 
as otherwise one or two stations would surely 
suffice for the whole of such a very small terri- 
tory. 

An encouraging sign of the sensible way in 
which the Postmaster is seeking to wield his 
power justly, and in such a manner as not to 
interfere with the progress of the art, is shown 
by his acceptance of the recommendations of a 
committee of broadcasters, that he should ap- 
point a Board to advise him in all the technical 
points involved in radio supervision. This he 
has done and the personnel of the Board is a 
source of encouragement to the radio public, 
according to a news item in the Wireless World 
and Radio Review.' Among those appointed 
is A. Campbell Swinton, who was President of 
the Radio Society of Great Britain from 1913 
to 1921. He will prove a valuable guardian 
of the interests of the British radio public. 

But another governmental activity has lately 
served to arouse Gus;lielmo Marconi himself. 



Adventures of a Wireless Free-Lance 



27 



The report in question had to do with the 
operation of the Imperial Wireless Communi- 
cations, and suggested the limitation of private 
enterprise in the radio field to such an extent 
that Marconi felt that its development would 
be much hampered. This is of especial im- 
portance to Marconi as he feels about ready 



to go ahead with his directive radio, on a 
large scale. He feels that suitable radio 
mirrors can now be constructed, that beams of 
radiations can be thrown across the Atlantic or 
even to South Africa, with a resultant dimin- 
ution in interference between stations and a 
very considerable saving in the power required. 

J.H.M. 



Adventures of a Wireless Free-Lance 

My First SOS A Farce Comedy 
By GEORGE F. WORTS 



THERE was nothing in the least 
amusing about it when it was hap- 
pening. We were soberly and sol- 
emnly aware that the most dramatic 
situation that can arise in the life of 
a ship confronted us. The North American 
was fast aground and lost in a heavy fog. 
Five hundred passengers, mostly women and 
children, were endangered. Responsibility for 
all these lives had been suddenly dropped upon 
our shoulders. A heavy swell the aftermath 
of a gale was lifting us and dropping us with 
great thumps upon a rocky shoal somewhere 
in the Strait of Mackinac; and the ship was 
canting dismayingly to starboard. 

it was a tremendous moment. I had been 
"pounding brass" for two years, and here at 
last was the opportunity for which 1 had been 
secretly and shamefully hoping the opportun- 
ity, I suspect, for which every youthful wireless 
operator secretly and shamefully hopes of 
sitting down at the key and rapping out the 
three most electrifying letters in the alphabet 
SOS! 

1 had retired to my stateroom a little after 
six o'clock from the midnight-to-six watch, 
and was asleep when it happened. A sudden 
jar, a deep banging, startled me awake. We 
had, I learned later, taken the wrong bearing 
on a certain light during the night, and were a 
mile or two off our course. 

1 sprang from my bunk and put my head out 
of the porthole. Cold white fog streamed past 
my face. We had been creeping through 
fog when 1 had turned in, and it seemed to me 



that the fog had become thicker. It was im- 
possible to see farther than twenty portholes 
in either direction and the white hull above 
me vanished into creamy nothingness. 

From every porthole within range a head 
protruded, nose down. Some were men's 
heads and some were women's heads adorned 
with braids, kid-curlers and lace caps. Every 
one was gazing at the water, and no one said a 
word. 

The engine had stopped and the ship was as 
still, as peaceful as though we were at anchor 
in some snug, quiet harbor. Then a long wave 
rolled out of the fog and lifted us. We settled 
down again with a harsh scraping sound and 
the whole ship seemed to shiver as we listed to 
starboard. 

A woman at a porthole above me said, in an 
amazed voice, "Why! we're aground!" She 
did not seem alarmed. In fact, no one seemed 
alarmed. That, to me, was astonishing. 1 
had heard that in moments such as this every 
one became panic-stricken. The excitement 
came later. 

We all stared with fascination at the water. 
It was pale blue and so clear that we could 
easily see the stones on the bottom. They 
were of all sizes, some as small as golf-balls, 
some as large as basket-balls. 

My stateroom door opened and Kenneth 
Little, the junior operator, burst in with a white 
face and excited eyes. He was grinning nerv- 
ously. 

"Well!" he got out breathlessly. "We're 
on!" 



Radio Broadcast 



We exchanged glances with which every 
wireless operator can sympathize. Our great 
moment had come! No longer were we the 
playthings of passengers luxuries forced upon 
unappreciative owners. We were, provided 
the North American did not back off the shoal 
under her own power, the two most important 



^ '_ r i I*L, 




"FROM EVERY PORTHOLE WITHIN RANGE 
A HEAD PROTRUDED, NOSE DOWN" 

individuals on board the ship! We were 
about to become heroes! 

"Can she get off by herself?" I asked anxi- 
ously. 

He didn't believe so. She had been running 
through the fog at half-speed and she had sud- 
denly been brought to a jolting stop. It 
wasn't conceivable that she could back off that 
ledge. 

Another wave lifted the beautiful white bulk 
of the North American and dropped her with a 
harsh deep booming still farther up on the shoal. 
The hull trembled as the engine started full 
speed in reverse. A glance from the porthole 
assured me that steam was being wasted. 
The golf-balls and the basket-balls remained 
stationary while bubbles from the propeller 
swept forward. 



I had always pictured myself, when this 
moment came, as a man of coolness, courage, 
and decision. 

"Get back on the job," I said crisply. 
"Stand by and wait for me. Test out the 
emergency outfit. Call up the engine-room 
and tell 'em we'll want plenty of juice." 

"Hadn't 1 better send out an S O S?" he 
inquired hopefully. 

"Not by any means," I said. "Stand by 
and wait for me." 

"Stand by" is a phrase that has always 
appealed to me, along with other nautical 
terms such as " Steady as you go," and " Bright 
light two points off the port bow, sir!" 

When 1 entered the wireless room the tele- 
phone from the pilot house commenced to ring. 
The first mate nervously wanted to know if 
everything was all right with us. I reported 
that we were standing by and ready to send an 
S O S at a moment's notice. He told me rudely 
to keep my shirt on and not to send an S O S 
without the Captain's explicit orders. 

I asked him if there seemed to be much 
chance of our backing off the shoal under our 
own power. 

" How do 1 know?" he said irritably. "Stay 
where you are and don't go fooling around the 
decks. We may need you." 

It appeared that, in the opinion at least of 
the first mate, I was not yet the man of the 
hour. I devoted myself to an inspection of 
the apparatus. 

The wireless room was situated in the star- 
board after corner of a square hall between- 
decks known as the "social hall." At one 
corner of the social hall was the purser's office. 
Across from that was the steward's office. I n 
another corner was the baggage room; and in 
the fourth corner was the large glass and 
mahogany cage housing the radio apparatus 
and the newsstand. We ran the newsstand 
sold magazines, candies and cigars in addi- 
tion to operating the wireless. 

Our transmitter was a 2 k. w., 24O-cycle 
rotary synchronous set the first of its kind to 
be installed on the Great Lakes, and a source 
of endless trouble. Our receiving set was a 
heritage from United Wireless days, a loose- 
coupled tuner and a carborundum crystal 
detector in which we defiantly used silicon and 
a cat-whisker of mandolin E-string. The 
audion had yet to cast its pale glow upon 
radio scenery. 

If the first mate did not appreciate our in *- 



Adventures of a Wireless Free-Lance 



2Q 



portance, certainly the passengers did. They 
swarmed about the newsstand, asking no end 
of idiotic questions. How long would we be 
aground? Did the Captain know where we 
were? Was the fog going to lift? Were ships 
coming to our relief? How did we know if 
anybody was calling us when we didn't have 
those rubber things on over our ears? 

I made the interesting discovery that human 
beings in moments of great crisis crave chewing- 
gum. Every one wanted to buy chewing-gum. 
And so 1 have come to the conclusion that gum 
chewing is the American way of expressing 
deep emotion. 

We closed the newsstand emphatically. 
Somehow, selling chewing-gum to anxious 
passengers did not harmonize with 
the dignity of our position. We were 
wireless heroes, not chewing-gum 
salesmen! 

The long waves continued to roll 
up under the stern from out of the 
fog, driving the ship farther and 
farther upon the ledge and tilting 
us more and more to starboard. The pounding 
did not excite the passengers, but the listing 
did. The opinion prevailed that the North 
American \vas about to turn turtle. 

Within half an hour after the first impact, 
many of the passengers put on life-belts. The 
social hall was in a hubbub. Every one was 
asking every one else questions. 

The second assistant engineer covered with 
mud and rust raced through the social hall and 
demanded the use of our telephone to the pilot 
house. He had been down in the bilges and 
wanted to inform the Old Man that no visible 
damage had been suffered by the garboard 
strakes. 

"She isn't taking any water, but we're stuck 
tight," he reported excitedly. 

The first mate asked for me. 

"The Captain wants you to get hold of 
Mackinac Island and have a tug sent out." 

"Yes, sir!" I snapped. "Where are we?" 

They didn't, it developed, know exactly 
where we were. 

"On one of the Duck s," he guessed. "Tell 
the tug to nose around the Ducks. We're 
probably on Little Duck." 

"Yes, sir!" I snapped. A picture came into 
my mind of the Old Man and 1 in the act of 
leaving the ship sticking to our posts to the 
very last, while the ship was ground to flinders 
on one of the Ducks. 




This vision possibly was prompted by a 
sudden and sickening realization that the 
Mackinac Island operator would not be on the 
job for at least an hour. It was still very early 
in the morning. 

There was nothing else to do, so I started 
the motor-generator and called WHQ the 
Mackinac Island station. There was no re- 
sponse. At that time of day no one was on 
the air. Even the static seemed to be reposing. 

The telephone rang again, and this time the 
voice of the first mate was agitated. 

"Has that tug started?" he wanted to 
know. I told him that the Mackinac Island 
station wasn't open and wouldn't be open 
for another hour. 

" You've got to get word to Mack- 
inac somehow," he said. "We can 
see land now. We're on Little Duck. 
This wind is freshening. There isn't 
any time to lose, Sparks. Get busy!" 
I got busy. Futilely I called 
WHQ. I called and called and called. 
The operator probably hadn't left 
his boarding house. It was a tormenting 
situation. In desperation I called VBB, the 
Canadian Marconi station at Sault Ste. Marie. 
Someone was always on duty in VBB. He 
could put the message on the land line to 
Mackinac Island. Then I realized with a sen- 
sation of sickness that the Western Union 
office at Mackinac Island did not open until 
WHQ opened. 

VBB did not answer. 1 called him feverishly 
for five minutes. Then I rang the pilot house. 
The Captain answered. I told him that I had 
tried to raise Mackinac Island and the Soo, 
but that no one answered. 

"See if there isn't some ship near us," he 
replied. 

"That means an S O S," I told him. 

"All right send as S O S!" he snapped. 
" But get somebody. What are you fellows 
being paid for?" 

And so the great moment came, not pre- 
cisely as I had wished, perhaps; but here, at 
all events, it was. After two years of faithful 
brass pounding I was about to send my first 
SOS! I was divided between perspiring 
agitation and a consciousness of the part I 
played in this epic maritime drama. 

Kenneth, the junior operator, looked at me 
enviously as I slipped into the chair and grasped 
the handle of the motor-generator starter. 

"SO S?" he gasped. 



Radio Broadcast 



" Yes," I said fatefully. " I t's S O S ! Keep 
that door shut! There's somebody else who 
wants some gum!" 

It opened even as I shouted the warning. 
A perspiring young man with disheleved hair 
and wild but determined eyes forced his way 
inside. The eyes of dozens of passengers on 
the other side of the glass stared at us expec- 
tantly. In his hand the young man had clasped 
a sheaf of papers covered with pencilling. He 
was a reporter on the Chicago Examiner, and 
this story was, of course, a big one. Nearly all 
of our passengers were Chicago people. It 
was a front-page story, worthy of a seven- 
column streamer. 

He shoved the pile of paper at me. 

" 1 want to get this right off," he panted. 
" It's press. It has right of way over all traffic. 
It's to be sent collect." 

He produced documentary and other evi- 
dence to support the statement that he actually 
was a reporter. Sweat was streaming down his 
face, and sweat was streaming down mine. 
1 was trying to push him out of the room. He 
was trying to push me into my chair. We 
weren't making much progress 

" Look here," I said dramatically. " I am 
in the midst of sending an S O S. How dare 
you break in here!" 

"The devil you are!" he cried. He snatched 
the paper from my hands and wrote rapidly 




I AM 

sos. 



IN THE MIDST OF SENDING AN 
HOW DARE YOU BREAK IN HERE!" 



on the top sheet: " Radio men sending frantic 
calls for help!" I glanced bewilderedly over 
his shoulder at other things he had written. 
The North American, 1 learned, was slowly 
being pounded to fragments by a savage sea 
on the gleaming fangs of a rockbound coast. 
Women and children were running screaming 
about the decks. The ship's officers were 
determinedly setting them an example of cool- 
ness and courage. The lifeboats were in readi- 
ness. A furious gale was blowing up. The 
lives of five hundred Chicagoans were in acute 
peril. 

"That's bunk, " I snorted. "I won't send 
that stuff. We aren't being pounded to 
fragments. Nobody's screaming, and a gale 
is not blowing up. You better let the skipper 
see that." 

"This is press," he shouted. " If you don't 
send it, I'll have you prosecuted! There's a 

law that says that says ." 

" If you don't clear out of here," I stopped 
him, "I'll have you put in irons. You're 
interfering with the despatch of a distress 
signal." I appealed desperately to my partner. 
" Ken, get him out, will you?" 

Kenneth grappled with our natural enemy 
while I sidled into the chair and started the 
generator. The reporter broke away from 
Kenneth and shoved his one-act melodrama 
beside my sending arm. My hand was already 
at the key. 

"Won't you please get it 
off when you're through with 
that SOS?" he begged, and 
there were tears in his eyes. 
" I'll have to edit it first," 
I said angrily. 

" If you touch a line of 
that copy," he shrieked, 
"I'll have you jugged the 
minute we hit Chicago! I'll 
break you! I'll beat you 
up! I'll have your license 
taken away! I'll 

Kenneth pushed him out 
into the crowd in the social 
hall, and he was shaking 
with sobs. I could have 
brained him. Hehad cheap- 
ened my grand dramatic 
moment and set every nerve 
to jumping. 

My fingers danced on the 
key. 



Adventures of a Wireless Free Lance 



"Are 



"Z Q P!S B!F S!" the spark stam- 
mered. Then I steadied my hand and ripped 
off a string of very creditable S O S's. 

1 threw over the aerial switch to the receiv- 
ing position. The mournful lazy drawl of a 
big ore freighter came instantly out of the fog. 
The name of the ship is forgotten. 

"Where are you, O M?" I have always dis- 
liked operators who use that solicitous and 
ingratiating phrase O. M. "old man." "Are 
you sinking, O. M? You come in good and 
loud, O. M. Stick to the ship, O. M." 

I coldly informed him that our danger was 
not yet acute, that we were aground on Little 
Duck Island and wanted to have 
some one tow us off. 

He replied with a series of irrit- 
able "9'$". That meant, in those 
days, " I am being interfered with." 
I wondered who could be jamming \ 
us, and while I wondered the smooth 
buzz of VBB, the Soo, enlightened 
me. 

"What is your position?" he asked, 
you in immediate danger?" 

1 told him to stand by, that he was jamming 
me, and called the ore boat. VBB came back, 
insisting on having my position, and a report 
on the character of our predicament. He addi- 
tionally wanted to know why 1 had sent an 
SOS without first calling him. My nerves 
were on edge from that tiff with the reporter, 
and I told him sarcastically that it was a real 
nice day and I hoped he had enjoyed his smoke. 
I used profanity freely. 

He informed me that the use of profanity 
was strictly forbidden on aerial circuits and 
was punishable by a fine and a long term of 
imprisonment under section i I2-A or 233-6 or 
40-1 i-X of the International Radio Regulations. 

" You should be ashamed of yourself to use 
such language in a situation as grave as this." 
Presumably he meant that my chances of get- 
ting into Heaven were imperiled. He finished 
his sermon, and 1 again addressed my invisible 
friend on the freighter. Where were they? 
He reported that they were just rounding 
McGuipin Point, northbound, which meant 
that it would take them hours to reach us. 
That hope was too dim. 

I resorted to a few more SOS calls, mingling 
the distress signals with calls of WHQ, and, 
when I signed off, WHQ's rasping spark ans- 
wered. In all of my years of operating, I have 
never been so relieved to hear a spark. 




Complications immediately ensued. The 
operator at WHQ (there was but one) was then 
very new to the game. I am glad to say that 
he later became an expert operator. 

His reply to my S O S was bewildering. 
After wishing me a courteous good morning 
and making inquiries touching upon the state 
of my health, he sent me all of the baseball 
scores for the previous day. He then pro- 
ceeded to furnish me with long selections from 
the overnight news. He was not absolutely 
to blame. For time-saving purposes, we had 
abbreviated the request for ball scores to the 
three letters S B S send ball scores. The 
similarity between S B S and SOS 
is noteworthy. Perhaps he was 
sleepy that morning. 

When he was through regaling me 
with the topics of the day, I slowly 
and patiently informed him that it 
was succor and not base ball scores 
that I had asked for. Here we were, 
piled up on the rocks, every moment 
precious, and he was using perfectly good 
electricity to tell me that Charlie Chaplin had 
just signed a contract for $1,000 a week. 
Good God! 

For several seconds there was no intelligible 
response from him only the stuttering of his 
spark as his paralyzed hand tried vainly to 
work the key. In broken Continental he 
presently told me to stand by a moment while 
he telephoned the waterfront for a tug. . . . 
And so my heroic moment came, was lived, 
and passed. 1 telephoned the Captain that a 
tug was on the way. 1 read the stirring one- 
act melodrama with its cast of five hundred 
screaming women and children supported by 
the ship's officers who set their cool and cour- 
ageous example. I tore it up and dropped it 
into the wastebasket. We were on a popular 
run; and that story, had it been published in 
Chicago, would have ruined our passenger 
business for the rest of the season. The re- 
porter threatened me with sundry revenges, 
none of which I suffered. 

After WHQ had assured me that the tug 
was on her way, the tension subsided. It was 
all over. Kenneth and I were once more com- 
mercial wireless operators. A wonderful op- 
portunity had been given us to do a land office 
business. 

"Go out and pass the word around," I 
suggested, "that when news of this reaches 
Chicago, all their relatives and friends will be 



Radio Broadcast 




'LOOK! THERE GOES THAT WIRELESS OPERATOR!" 



scared green. Drop the hint that it would be 
a good plan to send radios reassuring them." 

It worked very nicely. Kenneth took charge 
and I went on deck for a breath of fresh air. 
The fog had evaporated and the warm Michigan 
sun beat brightly down upon sparkling blue 
water and a little island covered with ever- 
greens a few hundred yards ahead. The news 
had travelled magically over the ship that a tug 
was on the way from Mackinac Island and that 
there was nothing now to worry about. 

I was proud of myself. Very few wireless 



operators had gone through this ordeal. I 
had sent my S O S a very authentic and 
dramatic S O S and was one of that noble 
company captained by Jack Binns. I glanced 
up affectionately at the smoke-blackened four- 
strand antenna and heard a man exclaim: 

" Look! There goes that wireless operator!" 

And a very pretty girl said, in awed tones, 
"Gee whiz!" 

I pretended not to hear. With head up and 
shoulders back, I proceeded on my way. 

Don't be uncharitable. 1 wasonlv nineteen. 




USING HONEYCOMBS IN THE KNOCK-OUT REFLEX 



THE use of different forms of induc- 
tances in the RADIO BROADCAST 
Knock-Out Reflex circuit, such as 
the straight winding and the spider- 
web heretofore described in this de- 
partment, has suggested to many of our readers 
and to the RADIO BROADCAST laboratory staff, 
the possibility of using the honeycomb induc- 
tance. Our experiments have shown that the 
experimenter and builder will encounter little 
difficulty in adopting this form of inductance as 
the main winding in the reflex circuit. 

In reference to the diagram shown on page 
327 of the February RADIO BROADCAST, our 
readers who have been following up the de- 
velopment of this circuit (and they are many) 
will recall the following specifications for Ti 
and T2. Using a two and a half inch tube, the 



secondaries were first wound, sixty turns being 
used for each transformer. The primaries 
consisted of fifteen turns for Ti and thirty-five 
turns for T2, wound over the secondaries, with 
an insulating layer of paper between. 

The simplest way of substituting the honey- 
comb coils, is using them as the secondaries, 
winding the primaries over them as usual. 
Figs, i and 2 show a set built up in this manner. 
Honeycomb or duo-lateral coils, No. 75 were 
used as the basic inductances. Twenty-five 
turns of wire were removed from each coil, 
leaving 50 turns (in the case of the DL, the 
equivalent). The inductance per turn of the 
honeycomb coil being greater than that of the 
layer type inductance, the result is about equal 
to the usual sixty turns. An eighteen-inch 
strip of cardboard is wound over each secondary 




FIG. I 
Front view of reflex and two step, using honeycomb inductances 



34 



Radio Broadcast 




Rear view of reflex and two step using honeycombs. Amperite resistances have been used in place of rheostats 



coil which acts as an insulating layer between 
the two windings. The cardboard also loosens 
the coupling, increasing the selectivity of the 
set. 

The 1 5- and 35-turn primaries are now wound 
over the secondaries. The 1 5 turns present no 
problem whatever. However, due to the nar- 
row winding space, the 35-turn primary must be 
single bank-wound. Details on bank-winding 
will be found in the Grid department of the 
February RADIO BROADCAST. 

The reader may find it easier to make the 
primary windings, by building up the winding 
"form to the correct size, and slipping it over 
the secondary when wound. 

The completed reflex (Fig. i) plus two stages 



audio was constructed in accordance with the 
instructions outlined in the February RADIO 
BROADCAST. The anti-squeal condenser is a 
.001 mfd. Dubilier Micadon. However, a 
larger panel, 7" x 18" was used. This permits 
a nicer layout, with less cramping of instru- 
ments. The panel working drawing is shown 
in Fig. 3. The base is 17!" x 6f" x f ". The 
sockets are spaced three inches between centers, 
as are the jacks. Thirteen-plate, or .00025 mfd. 
variable condensers were used, with four-inch 
dials. Due to the size of the panel, it was 
thought better to support it by brackets, rather 
than permit the entire strain to be taken up by 
the rigid wiring and the screws into the base. 
The brackets were made from brass strips, 




FIG. 2A 



In the R. B. Lab 



35 



COIL 



eight inches long, one half inch wide 
and ifa inch thick 

A NOVEL BINDING-POST STRIP 

WE CALL the attention of the 
reader-experimenter to the 
mounting of the binding-post strip 
which, perhaps, will appeal to him as 
a novel and efficient method of pro- 
viding for rear connection in all ap- 
paratus having two similar audio 
transformers. This method elimi- 
nates a bit of machine work, con- 
serves space, and raises the binding- 
posts to a convenient height for 
soldering connections to the nuts. 



BACK-OF-PANEL MOUNTING 
FOR SPIDER-WEBS 

(Data by MR. GEORGE BEANE, JR.) 

MANY of our readers have re- 
frained from using spider-web 
coils, a very efficient form of induc- 
tance, due to the fact that mounted 
in the conventional way on the front 
of the panel, they are a clumsy and unsightly 
projection. Mr. Beane, however, has obviated 
this objection in an ingenious and very efficient 
manner efficient because of the possible 
micrometer adjustment, and the absence of 
body capacity effect. 

The drawing, Fig. 4, explains the idea so 
clearly that there is little need for a detailed 
description. 

The wood strips to which the coils are 



-RUBBER B&NDS 




FIG. 4 
How to mount your spider-web coils behind the panels 

fastened, are cut from a cigar box. They are 
glued to the inductances, and to small blocks 
at the inside or panel end, to which are screwed 
small brass hinges obtainable from any hard- 
ware store. 

The brass rods threaded into the knobs and 
panel may be any convenient size and thread. 
The ends against the hinges should be filed 
round. 

If, for the sake of appearance or dials, it is 



O i" 



-n"- 



n 



-9- 



-o 



UNMARKED HOLES DRILLED 
TO CLEAR N. 8 SCREWS 




18" 



FIG. 3 

Panel layout for the reflex and two step 



Radio Broadcast 



desired to separate the control knobs farther 
than shown in the main sketch, this is easily 
done by glueing an empty thread spool be- 
tween each wooden arm and the coil, as shown 
in the insert. 

Rubber bands supply the tension tending to 
bring the coils into close inductive relation. 
By adjusting the bands on different prongs, 
the tension may be varied. 

Honeycomb coils mounted in this manner 
will appeal to the experimenter using the three- 
coil tickler regenerative circuit, advocated as 
a standby set in the March Grid department, 
and the super-heterodyne, in which a very 
efficient oscillator-coupler may be made of 
spider-web inductances. For the latter RADIO 
BROADCAST suggests a winding form having 
an odd number of spokes, about nineteen, with 
a beginning, or minimum diameter of one and a 
half inches. The pick-up, secondary and 
tickler coils should be wound with respectively 
25, 35, and 50 turns of wire. 

AN OPERATING SHELF FOR THE 
PORTABLE AUTOMOBILE SET 

I Photo by MR. C. H. BROWN 

A CARRY ING-CASE arrangement for the 
ideal portable automobile receiver was 
described in this department last month. That, 
however, is only one-half the story. The oper- 
ation of even the most suitable equipment is 
rrarred if it is set up on the running-board, 



OUTSIDE ANTENNA __ 
ABOUT 100 FT. LONG 




SECOND FLOOR. 



LIVING ROOM 



POLARITY 
RECEPTACLE 



DINING ROOM 



FIRST FLOOR. 



TO GROUND 



CELLAR 




TO GROUND 



FIG. 6 
A tentative plan for wiring your house for radio 



FIG. 5 
The windshield shelf for the portable auto-set 

the rear seat of the car, or on the ground at the 
mercy of clumsy and careless picnickers. 

Mr. Brown, who designed the carrying-case 
and equipment, has devised a clever windshield 
shelf for the operation of his set, from a com- 
fortable seat at the most convenient operating 
height. The photograph of Fig. 5, with the 
insert, clearly explains the construction and 
mounting of the shelf. 

The lead-in and beginning of the antenna 
are also shown in the photograph, and exhibit 
the neatness and system which adds so materi- 
ially to the comfort and pleasure of auto 
radioing. The shelf should be used, of course, 
only when the car is standing still. 

The interested reader will find 
other details on the portable auto 
equipment in the April Lab De- 
partment. 

WIRE YOUR HOUSE FOR 
RADIO 

ARE you at present building a 
home, or having plans .drawn 
up for one? If so, instruct your 
architect when making provisions 
for electricity, plumbing, heat, etc., 
not to forget your radio receiver 
which has become as important a 
convenience as the less novel facili- 
ties. 

Fig. 6 indicates the scheme fol- 
lowed out by Mr. George Hofe of 
South Orange, New Jersey, in which 
antenna and ground outlets are 
provided in all rooms where he will 



TO GROUND 



In the R. B. Lab 



37 



be likely to enjoy reception. In Mr. Hofe's 
new home, he will plug in his radio set as you, 
perhaps, now do your electric toaster or vac- 
cum cleaner. 

Polarity receptacles and plugs are used. 
This insures the correct line up of antenna and 
ground without experimental plugging-in. A 
three way switch, close to the entrance of the 
lead-in, makes it possible to cut off all indoor 
leads if at any time, it should be deemed 
desirable. 

Individual grounds are provided at each 
polarity receptacle. 

The architect, in designing your particular 
home, might go even farther, and, taking into 
consideration surroundings, trees, etc., and, 
perhaps, provide antenna mooring in the way 
of an artistic mast or tower. 

A STANDBY RADIO FREQUENCY 
SET 

MANY of our readers, perhaps not desiring 
to hazard some of the newer radio fre- 
quency developments, have requested a con- 
ventional radio frequency circuit, which may 
be depended upon to work without excessive 
experimentation. And there are many rather 
hasty enthusiasts who would benefit from 
building such a set before venturing on the 
more precarious Grimes arrangements and the 
super-heterodyne. 

Complete descriptive drawings of such a 
layout are shown in Figs. 7 and 8. The parts 



are ^all standard, and we suggest, as R. F. 
transformers, such reliable makes as the Acme 
or Murad. A 7" x 24" panel will be about 
right. 

A square solenoid or box loop is suggested, 
four feet on a side. Nine turns of wire, spaced 
one half inch, will cover the entire broadcasting 
range. If it is desired to use an antenna, with 
greatly increased range and volume, a tuning 
coil, such as described by Mr. Sheehy in the 
Laboratory Department for March, may be 
wound. 

This combination has enabled James \V. 
Brennan, of Beverly, Mass, to build up a very 
creditable DX record. 

BUILDING YOUR OWN LAB 

FIG. 9 shows how to use dividers, RADIO 
BROADCAST'S suggestion for this month's 
addition to the growing amateur labora- 
tory. Seven inch dividers is the most common 
size, and should cost in the neighborhood of 
seventy-five cents. They are as indispensable 
to fine -panel layout, as is the compass in 
drawing. 

In combination with the ordinary one foot 
rule, many otherwise difficult panel maneuvers 
become as easy as drawing a straight line. No 
templates are required for the mounting of 
variable condensers, rheostats, etc. The cor- 
rect distances are measured with the ruler, to 
one thirty-second of an inch if necessary, and 
the dividers are spread to span this exactly. 



R.F.T. 



R..F.T. 



A.F.TRANSF. 




FIG. 7 
The circuit for a standard transformer coupled R. F. set 



Radio Broadcast 




The intelligent use of dividers will cut the time 
of preparing a panel for drilling by half. 

A NOVEL USE FOR DIVIDERS 

THE R. B. LAB has found the dividers a 
most handy tool to facilitate the soldering 
of connections to small condensers of the 
Dubilier Micadon type. The points of the 
dividers are placed through the eyelets of the 
condenser, and the spring released. The 
condenser is thus held firmly, and may be 
moved about and adjusted for soldering in 
places inaccessible to fingers. 



FIG. 9 
How to use dividers 



One way to eliminate undesirable radiation 
from your single circuit regenerator is to use Mr. 
Bouck's "Reflexit" (see page 7). Later numbers 
of this magazine will contain, in the Lab Depart- 
ment, instructions on how to convert other types 
of oscillating receivers to unoffending circuits. 



o o 




BASEBOARD- 

FIG. 8 
The panel layout and base, showing the placing of instruments 



How to Build a Resistance- Coupled 

Amplifier 

An Inexpensive Three-Stage Amplifier Unit Which Will Give Distortionless Amplification 

By G. Y. ALLEN 



Westinghouse Electric & Manufacturing Company 






HE three-electrode vacuum tube is in 
itself a very good amplifier of elec- 
tric voltages. Tubes have been con- 
structed whose plate-to-filament vol- 
tages range as much as thirty to forty 
times the grid-to-filament voltage variations. 
Furthermore, within certain limits, this voltage 
amplification is substantially a linear relation. 
Where power must be absorbed from the out- 
put side of a tube, however, high amplification 
factors, with their accompanying high plate 
impedances, require high B battery voltages in 
order to maintain the linear relationship be- 
tween the input and output sides. These con- 
siderations limit the design of practical tubes 
to those having an amplification constant of 
from 6 to 8 and plate impedances ranging 
around 20,000 ohms. Such tubes work very 
well as amplifiers using from 45 to 150 volts 
B battery. 

THE PLACE OF THE TRANSFORMER IN AUDIO 
AMPLIFICATION 

NOW it is a well defined law in electrical 
engineering that the most efficient con- 
ditions are met in any device supplying electric 
power when the impedance drop across the 
power consuming device is the same as the 
impedance drop across the device supplying 
the power. When using two or more tubes in 
cascade amplification, the grid circuit of any 
tube is the load consuming device for the plate 
circuit of the preceding tube. But the grid 
impedance of a vacuum tube as it is used in an 
amplifier is very much greater than the plate 
impedance. Thus, if two or more tubes are 
connected directly in cascade without inter- 
vening apparatus, great amplification will not 
result. This condition has made very popular 
the practice of using step up transformers be- 
tween the plate circuit of one tube and the 
grid circuit of the next tube, which transformer 
presents to both the grid and plate circuits im- 
pedances permitting the tubes to be worked 



at their most efficient point. Furthermore the 
inherent voltage amplification factor of the 
tube is multiplied by the step up ratio of the 
transformer resulting in greatly increased am- 
plification per stage. 

Were amplification all that were to be 
considered, transformer-coupled amplification 
would be ideal. With the advent of good 
broadcast transmission, however, and with 
the production of good loud speakers, the 
broadcast listener's standard of quality has 
crept steadily upward. A transformer, being 
essentially an inductance cannot transform all 
voice frequencies with exactly the same am- 
plification no matter how carefully designed, 
with the result that all amplifying transformers 
suppress the lower and favor the higher fre- 
quencies. True, great improvements have 
been made in transformer design, but the fact 
remains that fundamentally the transformer 
cannot ever give distortionless amplification. 

WHEN RESISTANCE-COUPLED AMPLIFIERS ARE 
DESIRABLE 

FOR those who demand quality at all cost, 
the resistance-coupled amplifier is un- 
questionably the most desirable. The ampli- 
fication per stage is not as great as with 
transformers, but a nearly absolute linear re- 
lation holds between input and output. 

A curve showing amplification plotted 
against frequency for a transformer as com- 
pared with the linear relation existing in a 
resistor is shown in Fig. 2. It will be noted 
that the amplification of a transformer, and 
the curve is shown for one of the best trans- 
formers on the market, falls off very rapidly 
below 200 cycles. In other words, all notes 
below middle C on the piano are reproduced 
much below their normal amplitude with result- 
ing loss in quality. On the other hand (Fig. 3), 
the amplifier using resistance-coupling shows 
nearly constant amplification throughout the 
range of frequencies plotted, although some- 



Radio Broadcast 



what less in amplitude. To compensate for 
the reduction in amplitude, it is generally 
customary to use one more stage than would 
be used in a transformer-coupled amplifier. 

In designing a resistance-coupled amplifier, 
the theory indicates that the greater the values 
of the coupling resistance, the greater the am- 
plification per stage. That statement can be 
proved this way: 

Let E B = AC grid voltage of first tube. 

E P = AC plate voltage of first tube. 

Rp = AC plate resistance of first tube. 

I,, = AC plate current. 

fj. = voltage amplification constant of tubes. 

Ri = resistance of coupling resistor. 
From fig. 2 it will be evident from Ohm's law that 

Ep=I P (Rp+Ri) 

ME g =!p(R P +R,) 



Also E' g = Ip Ri 
and E 1 s = f-E e 



R t (Assuming negligible impedance in 



Rp+Ri coupling condenser 



It is evident, therefore, that the greater the 
coupling resistance Ri, the greater will be the 
voltage applied to the grid on the second tube 
for any potential applied to the grid of the first 
tube, and therefore the greater will be the am- 
plification. 

However, it is plainly evident that the 
coupling resistor being in series with the plate 
battery will reduce the part of the plate bat- 
tery voltage applicable to the plate. There is 
an upper limit, therefore of coupling resistance, 
beyond which it is not advisable to go, on ac- 
count of the large amount of B battery re- 
quired. Fig. 4 shows the detailed circuit where 
R are the coupling resistances. 

WHAT YOU NEED 

THE photograph Fig. i shows very clearly 
the arrangement of the parts on the base 
board. That is the reason no base layout is 




FIG. I 



The complete unit mounted on a base. All wiring is protected by spaghetti tubing. The con- 
struction is not at all difficult and the cost of parts quite low. This amplifier gives perfect quality 



How to Build a Resistance-Coupled Amplifier 





TO.OOO aaooo 



FIG. 2 FIG. 3 

Shows the relation at various frequencies between the How the amplification varies in the resistance-coupled ampli- 



ratio of amplification to the frequency supplied to a 
transformer 



tier with an increase in value of the coupling resistor. Noth- 
ing is gained by using resistors of more than 100,000 ohms 



given. The list of the parts required is given 
below. 



APPROXIMATE 



A 1 , A ? , A 3 , Ward Leonard Resistance Tubes, 20,000 

ohms resistance ....... $2.00 



1.50 

75 

.50 
.50 
1.50 

-25 

.40 
.10 



Lavite Resistors 50,000 or 100,000 ohms 
manufactured by Crescent Radio Supply 
Co ......... ... 

B 1 , B 2 , B 3 , Any standard type of socket 

C 1 , C 2 , C 3 , Radio Corporation type UX 543 grid 
leak mounting ....... 

Grid leaks ......... 

D Carter Rheostat, 6 ohms ....... 

E Carter pin type jacks ...... 

F 1 , P, F 3 , Dubilier Micadons capacity 0.0025 
mfd. 

G 1 , G 2 , G 3 , Fahnestock Connector Posts 

(or similar standard parts can be bought, 
where the builder prefers one product 
over another). 



The rheostat and pin jacks are mounted on 
hard rubber, bakelite, or micarta panels which 
are attached to the side of the board. All of 
the other parts are mounted on the board. 

THIS AMPLIFIER IS SIMPLE TO CONSTRUCT 

THE amplifier described herein was de- 
signed at the suggestion of the editor of 
RADIO BROADCAST. It can be manufactured 
from parts that are readily obtainable and it is 
felt that the constructor will be well repaid 
for his efforts. 

The particular amplifier described was laid 
out with simplicity as the keynote. Its ap- 
pearance is more that of a schematic diagram 
than an assembled set, but the layout is ar- 
ranged for taking either Ward Leonard or 
Lavite resistors. These tubes are supported 
by small brass L pieces as shown in photo- 
graphs and the two detailed drawings. It 
was felt that in this way the basic design 
could be best described and that those desiring 
to incorporate a resistance-coupled amplifier 



in a cabinet could easily modify the arrange- 
ment of the parts to suit their conditions. 

Fig. 3 shows how the amplification varies 
with the increase of the coupling resistor. It 
will be noted that nothing is gained by going 
above 100,000 ohms and that the amplifications 
will be about 50 per cent, more using 100,000 
ohms over and above that obtained using 
20,000 ohms. 

The complete wiring diagram is shown in 
Fig. 5. If the parts are assembled as shown 
in the photograph, no difficulty should be 
found in following the wiring diagram. It is 
advisable to use No. 14 tinned copper bus wire 
covered with spaghetti, both for the sake of 
neatness and efficiency in operation. 

The connections to the Dubilier micadons 




FIG. 4 

How the coupling resistor is connected. The drawing shows 

the circuits involved in the impedance balancing between 

input and output of tubes in cascade for audio-frequency 

amplification 



are shown soldered in the photograph. A 
half inch ^ machine screw is inserted with 
its head supporting the tube and a nut run 
up for the purpose of clamping the flexible 
wire terminal of the resistor and grasping 
the screw tightly. The sketch shown in Fig. 
6 will make this construction clear. Fig. 7 



Radio Broadcast 




FIG. 5 

Complete wiring diagram of the 3-stage resistance coupled audio amplifier 
connected to the RADIO BROADCAST "Knock-Out One-Tube Reflex" set 



shows how to connect the Lavite resistor. Con- 
siderable skill is necessary to do this success- 
fully without damaging the condenser and 
unless the constructor has had considerable 
experience with the soldering iron, it will be 

advisable to clamp 
the wires tightly to 
the condensers by 
inserting ^ inch A 
machine screws 
into the eyelets of 
the condensers. 




FIG. 6 

How the lead from the Ward- 
Leonard resistance tube is 
fastened to the connector 



B BATTERY VOLTAGE 



ACCOUNT 
of t h e fact 
that the 100,000 

ohm resistors are in series with vacuum tube 
plates, in the case of the Lavite tubes, approx- 
imately 20 per cent, of the available B battery 
voltage drop will take place across the re- 
sistor. Thus, the vacuum tube will get but 




FIG. 7 

How the Lavite re- 
sistor is connected 



80 per cent, of the 
voltage of the con- 
nected B battery. 
For most efficient 
results, therefore, 
at least twice 
the B battery volt- 
age normally used 
should be employed 
with the resistance 

coupled amplifier. Forty-five to ninety volts 
should be connected to the detector tube 
and from ninety to one hundred eighty for 
the amplifier tubes for loud speaker opera- 
tion. 

If moulded tube sockets are used manu- 
factured from some of the compounds that 
are not as good insulators as others, it may be 
found that on weak signals, the grid leaks are 
apparently unnecessary. On strong signals, 
however, the tubes will "block" unless the 
grid leaks are placed in the circuit. 



In the June RADIO BROADCAST will appear a com- 
plete how-to-make-it article by Zeh Bouck showing 
how to incorporate the j-stage resistance coupled 
amplifier with the "Knock-out One-Tube Reflex" 



Man -Made Static 

Definite Instructions on How to Eliminate Out- 
side Local Interference with Radio Receivers 

BY A. F. VAN DYCK 

Engineer, Technical Division, Radio Corporation of America 

PART II 



rTHE preceding article a general discussion of 
"man-made static," or inductive interference, 
was given, including a list of such causes of this 
interference as are commonly reported. We 
will now take up these causes individually, to 
- show how each originates and how each can 
be remedied. 

Lightning arresters 
used on power lines are 
not troublesome ordina- 
rily, because they pro- 
duce interference only 
when voltage is discharg- 
ing through them, which 
is seldom, or when they 
are being "charged," 
which requires only a few 
seconds each day and is 
usually carried out at 
times other than broad- 
casting hours. 

Arc lights are frequent 
and serious offenders. 

Arc light interference is very difficult, if not impos- 
sible, to eliminate. As somebody has said, the best 
way to eliminate this interference is to move one's 
home to a neighborhood where none of these lights 
exist. Arc light interference is particularly trouble- 
some because the light itself has somewhat of the na- 
ture of a spark, which sets up interference as explained 
in the previous article. Consequently, it is often 
the case that arc light interference can be eliminated 
only with great difficulty and very special means. 
Very often, however, the major part of the trouble 
comes from faulty insulation of the power line, or 
the lamp itself, because the voltage used in arc light 
systems is quite high and the insulation must be very 
good. A number of cases of arc light interference 
have been cured by replacing defective insulators, 
etc. Therefore in studying a case of arc light in- 
terference, one should make certain that faulty 
insulation of the line is not responsible, and that 
the lamp burns steadily without flickering. When 
this sort of power line is "leaky," the noise produced 
in radio receivers sounds very much like the "roll- 
ing" of a snare drum. 



Transformers on power lines are not troublesome 
very often, because they are inherently simple in 
design and construction, and are ruggedly and reli- 
ably built. A number of cases of loose connections 
on the terminal blocks of such transformers have 
been reported, however. That difficulty is simple 

to remedy. 



The Dealer and the Radio Owner 



Are asked and ask often, bow is my local 
electrical interference to be eliminated? Here 
are suggestions which will show the dealer how 
he can help bis customers get greater satisfaction 
from their sets, and the owner of a receiver to 
know where the trouble comes from, when there 
is trouble. 

Mr. Van Dyck has a simple remedy for 
every interference ill the broadcast listener will 
encounter. THE EDITOR. 



TELEPHONE LINES AND 
RINGERS 



T! 



ELEPHONE and 
telegraph lines do not 
often cause trouble be- 
cause of faulty insula- 
tion, because they do 
not carry much voltage 
so that even if the in- 
sulation of the line be- 
comes faulty no spark- 
ing is produced. How- 
ever, if a telephone line 
or cable is so located 
that near-by power cir- 
cuits induce considerable voltage in it, faulty insula- 
tion of the telephone line permits sparking of the vol- 
tage it receives from the power line. In one case of 
this sort, a telephone cable was located underground 
in a street which passed under an electric railroad. 
The heavy ground currents from the railroad set up 
electrolysis on the lead-sheathed telephone cable and 
finally ate through the lead and into the telephone 
wires. This action was possible whenever the cable 
became wet, as it did after every rainfall. For 
nearly one year, radio receivers in this neighborhood 
experienced bad inductive interference after every 
rain. The source was not found until the cable 
had been so badly damaged as to interrupt the 
telephone service, after which it was repaired by the 
telephone company, which of course eliminated the 
radio interference. 

It was said above that telephone and telegraph 
lines do not often cause trouble because of faulty 
insulation. They do cause trouble often, however, 
because of the kind of currents used. It is reported 
very frequently that telephone ringing machines 
cause interference. Usually the ringers which inter- 



44 



Radio Broadcast 



fere are the hand operated type, which is common 
in small communities. This interference is readily 
recognized by its intermittent nature, and the use 
of call signals. When the ringing generator is motor 
driven and causes interference it is of course contin- 
uous, and not intermittent as is the case with hand 
operated ringing generators. It is particularly severe 
in the immediate neighborhood of the telephone ex- 
change. Interference from telephone ringers can be 
eliminated usually, and always greatly reduced, by 
the use of a proper filter between the ringing keys and 
the machine. Such a device can be installed by any 
telephone electrician, and usually is arranged as 
shown in Fig. i. This arrangement is effective in 
preventing interference, although it does not affect 
the low frequency currents used for ringing, because 
it prevents the high frequency currents, which also 
are generated by the ringing machine, from going 
out on the lines. 

POWER COMPANIES COOPERATE 

IT IS interesting, and encouraging, to know that 
power companies are becoming interested in the 
interference problem to an increasing extent. Some 
companies are training men to locate faults causing 
radio interference. One company in the Middle 
West, has for several months past had a radio crew 
which is on duty nightly, and which responds to 
interference calls from any part of the city. This 
crew is equipped with a direction finding radio set 
mounted in an automobile, with which it is usually 



able to locate sources of interference quickly. A 
night spent on the job with this crew is an exciting 
experience, although if the night is one with the 
thermometer shrinking out of sight, the excitement 
is not unmixed with tingles of another sort. 

Those power companies which are most progres- 
sive in keeping their lines tree from interference 
radiation are those which have realized that the 





A SMALL TELEPHONE EXCHANGE 

Showing the hand ringers which may intermit- 
tently set up interference to radio listeners 



FIG. 



How to connect a filter to prevent interference from 
telephone ringing systems. L is a " etard" coil (# ?AA 
Western Electric, or its equivalent) and C is a con- 
denser of 8 mfd. 



wide-spread use of radio has helped their business 
materially, and as a result, they are doing what they 
can to help radio, knowing that the better radio 
reception conditions are in the territory they serve, 
the greater the electrical energy they are likely to 
sell. It has been observed that a neighborhood 
consumes markedly more electrical energy as soon 
as radio receivers become common in it. This is 
readily explained by the fact that the members of 
households equipped with radio sets stay more at 
home in the evenings, and also stay up later. There 
is many a home where the "midnight electricity" 
has burned nearly every night since radio entered 
in. Likewise the use of 
power to charge storage 
batteries has been a con- 
siderable item. Since this 
extra power is used at a 
time when other demands 
are light, it is a most de- 
sirable sort of load, and 
power companies which 
have appreciated this new 
factor are actively cooper- 
ating in reducing interfer- 
ence with radio reception. 

ELECTRIC PRECIPITATORS 

MANY cases of inter- 
ference have been 
caused by an electric de- 
vice, the precipitator, al- 
though these installations 
are not very common. 
The electric precipitator 
is used to prevent smoke 
or noxious fumes or ma- 
terial from leaving chim- 
neys. It operates by 
establishing a highly 
charged electric field in- 
side the chimney, of such 



Man-Made Static 



45 





1 
i 


**1 


-A 






1 










| 




- 


. H _ 


i 


1 






r n 


I 


I 

' 




* , S 


I R V fh ^ 


p 


\ 


""ti 




- i ' j i 


i 


! 








7/777 


i - 
I 


' 


^> I 





FIG. 2 

How to eliminate interference from an electric precipita- 
tor. A, grounded wire which must extend above the 
central high tension wires; C, the chimney; R, resistances 
of 2,000 to 5,000 ohms; S, screen around high tension 
wires; D, rectifier; H, screen around rectifier, trans- 
former, etc. 

a nature and direction that particles going up the 
chimney are charged and driven against the walls 
where they stick. After a sufficient deposit has 
been created, it is removed in some suitable manner. 

Precipitators have been used in concrete manu- 
facturing plants, chemical plants, incinerating plants, 
as well as in ordinary factories where coal smoke 
created a nuisance. In many cases, the precipitator 
does valuable work in preventing actual damage 
to surrounding vegetable and animal life. 

Precipitators cause interference for the reason 
that the high voltage used in their operation is ob- 
tained from an electrical device called a rectifier, 
which may generate high frequency alternating 
currents as well as the direct current which the pre- 
cipitators need. The high frequency currents are 
not useful to the precipitator and may be eliminated 
without affecting its operation. If the design of 
the precipitator is so arranged that the distance 
between the rectifier and the chimney is only a few 
feet, there is usually no trouble. 
But if the rectifier is separated 
from the chimney, the wire 
which joins them forms a good 
antenna which will radiate 
waves. This wire also runs up 
the chimney, but here it usually 
can not radiate, because there 
are other wires or metal sur- 
faces surrounding it and con- 
nected to the ground. Radia- 
tion from the precipitator 
system and consequent inter- 
ference with radio reception 
can be eliminated by placing 
a grounded mesh screen around 
the rectifier and the wire to the 
chimney. If screening of the 
various parts is impracticable, 
damping resistances can be in- 
serted which will prevent the 
high frequency currents from 
getting to parts of the circuit 
from which thev can radiate 



seriously. A little experimentation may be neces- 
sary, but it should always be possible to make in- 
terference from a precipitator negligible at distances 
greater than a few score yards from the installa- 
tion. The diagram given (Fig. 2) shows proper 
connections for an installation of the worst sort, 
that is, one where the rectifier and the chimney are 
separated by a considerable distance. 

Electric signs of the flashing kind are not trouble- 
some often, partly because they are not common in 
residential neighborhoods. Interference from this 
source can be minimized by keeping the switching 
contacts in good condition and by connecting resis- 
tances of the proper, size across the contacts. It 
can be eliminated entirely by putting choke coils in 
every wire going into the switch, including the main 
power lines. The choke coils must be capable of 
carrying the current which will pass through them. 

HOUSEHOLD APPLIANCES 

MOST household appliances are used only inter- 
mittently and for short periods. Interference 
is often experienced in the same house where the 
appliances are used, but rarely extends farther, if 
the appliances are in good condition. Devices 
involving small motors may need to have the motor 
brushes and commutators cleaned and cared for. 
Bad contacts in plugs, sockets, switches, etc., are 
much more apt to give trouble, particularly in flat- 
irons and other heating devices. In heating appli- 
ances the current used is relatively large and the 
service conditions are more severe due to the heat, 
so that bad contacts are quite likely to develop. 

Interference from door bells and elevator calls can 
be prevented by connecting a large condenser (2 
mfd. capacitance) across the device, or by connect- 




HIGH TENSION WIRES 



Like these cause frequent disturbance to the near by broadcast listener. Radio 
antennas at right angles to power wires such as these will pick up the least 

interference 



Radio Broadcast 



ing a "honeycomb" coil in series with each wire to 
it. In some cases, both condenser and coils may be 
necessary. In every case, the condenser or coil 
must be placed as close to the bell as possible. 

Violet ray outfits are serious disturbers of the 
peace, particularly since it seems to be popular prac- 
tice among owners to use them just before going 
to their beds, which is about the middle of the even- 
ing in the schedule of the radio fan. Neighborly re- 
quests to utilize the machines in non-broadcasting 
hours are usually effective. If not, the interference 
can be stopped by inserting choke coils in the power 
lines to the machine, one in each line. These may 
be made by winding three layers of No. 18 bell wire 
on a three inch tube with winding about six inches 
long. Then two condensers each having i mfd. 
capacity should be connected across the terminals 
of the machine and the mid-point connection 
grounded. This has been effective in several 
installations. 

It should be understood that the method of in- 
serting choke coils in the lines, which has been 
mentioned several times, requires the use of parts 
properly approved by the Board of Fire Underwriters 
as with all devices connected to the power lines in a 
house. 

HOW TO FIX MISCELLANEOUS INTERFERENCE 

AMONG the miscellaneous interference sources 
listed in last month's article, the X-ray 
machine is the worst. They are not very common, 
however. These machines radiate quite powerfully, 
and the radiations are sent out chiefly from the power 
lines from which is taken the power to run them. 
To prevent interference from X-ray machines, the 
method described for violet ray machines should 
be used. The size of wire used in the choke coils 
must be quite large enough to carry the current 
which the X-ray machine draws. Also additional 
condensers of the same size and method of connec- 
tion may be placed across the power lines where they 
enter the two choke coils. If it is desired to have a 
radio receiver close to an X-ray outfit, it will also be 
necessary, probably to enclose the X-ray apparatus 
in a grounded metal cabinet. 

Gas engines with electric ignition often give in- 
terference. The farm lighting plant is a common 
example of this. Part of this interference comes 
from the high tension leads and sparks at the spark 
plugs, and part comes from the contactor in the low 



voltage circuit. The radiation is usually at very 
short waves and is highly damped in character. 
Both of these factors make it difficult for the ordin- 
ary receiver to tune out the interference. The 
remedy is to replace all the ignition wiring with 
lead covered cable, the lead coverings being well 
grounded at frequent intervals and particularly at 
its ends. Of course if lead covered cable is used 
for the high tension wires, the insulation between 
the lead and the wire must be very good to stand 
the voltage. Sometimes heavy rubber insulated 
cable, wrapped with tin foil which is grounded, can 
be used. Occasionally it will be necessary to insert 
choke coils in the spark plug leads, right at the spark 
plugs. Such coils may be made with about 200 
turns of No. 36 double silk covered wire wound on a 
two-inch tube. These coils may have to be enclosed 
in a grounded metal box. 

The ignition system of automobiles radiates short 
waves in thesamemanneras that of thestationarygas 
engines described above. These can be heard only 
a short distance ordinarily, such as when the auto- 
mobile is almost directly under an outdoor antenna. 

Every broadcast listener should assist as much as 
he can, to locate and eliminate unnecessary inductive 
interference. Every listener should realize that 
broadcasting is only one of the many electric ap- 
plications upon which we have come to depend. It 
is also the latest, and as such it must do its share in 
accommodating itself to the others. It is quite 
unreasonable to expect that every power line, every 
motor, every electric device, shall operate at all 
times so as not to produce interference with the weak 
radio voltage received from some relatively small 
station hundreds of miles away. The broadcast 
listener must do his share by working with signals 
which are strong enough to dominate a reasonable 
strength of waves from other sources. The romance 
of reaching out to great distances of reception is apt 
to cause any one to forget that motors and other 
things must continue to operate. As broadcasting 
continues to develop, it will be found that several 
features will be improved, including better ratios 
of signal strength to strength of unavoidable inter- 
ferences. It may be necessary once in a while to 
have an "Inductive Interference Clean-up Week," 
but we can reasonably expect that interference 
troubles will decrease to a satisfactory degree, as 
radio takes, and is accorded, its proper place among 
the electrical services of mankind. 




Regeneration Without the Squeal 



By BOWDEN WASHINGTON 

Chief Engineer, Cutting and Washington Radio Corporation 



T 



HERE is some reason for each really 
new radio circuit, though many so- 
called new circuits seem to be 
brought out largely because some 
dealer is over-stocked in variometers, 
variable grid leaks or some other part, and 
therefore has his "radio expert" design a 
marvelous new circuit to help him get rid of 
them. 

WHAT CAUSES RECEIVING DIFFICULTIES 

IN RADIO receiving we are subject to four 
major kinds of interference. First, that 
from spark transmitters aboard ship. This 
is only severe along our seaboard and will be 
rapidly cured by the replacement of the obso- 
lete spark type with modern continuous wave 
or tonic train (I. C. W.) tube sets. 

Second, we have interference from near by 
broadcasting stations. This probably can be 
solved with sufficiently selective receivers. 
The writer has a receiver at his house '(this re- 
ceiver by the way is not a super-heterodyne) 
which is only three blocks from WLAG, -a 
typical 5oo-watt Western Electric Station, 
tuned to 41 7 meters, and has no difficulty what- 
ever in receiving distant broadcast from 380 
meters down and 441 meters up, with abso- 
lutely no interference. This same receiver 
at a distance of fifteen miles from WLAG 
experiences no difficulty on distant stations at 
411 while WLAG is operating on 417, so I 

think it can be said 

that this interference 
is no longer a funda- 
mental difficulty. 

Third, we have 
static, which, of 
course, can be very 
bad, but static is in- 
termittent, and troub- 
les us very little in the 
winter months and 
probably eventually 
will be largely elim- 
inated. 

Fourth, and worst, 
we have interference 



As far back as 1922, this magazine raised a 
protest against the use of "squealing" re- 
ceivers. And since that time, there have been 
a number of progressive and broad-minded 
manufacturers who have done their best to 
develop efficient, sensitive receivers to take the 
place of the ether agitators commonly called 
"bloopers." Dr. Bowden Washington reviews 
very ably, we think, the entire complicated 
situation and describes a new receiver his 
company has designed. This visible co- 
operation of manufacturers shows much po- 
tential good for the industry. 

-THE EDITOR. 



from transmitting or radiating receivers. The 
reason I say "worst" is that probably there 
is no solution for this malignant interference 
but the discontinuance of the use of this type. 

WHAT HAPPENS-WHEN YOU LISTEN WHILE A 
RADIATING RECEIVER IS "ON" 

IT IS impossible to evolve a principle which 
will eliminate noises received from single- 
circuit regenerative and similar offending re- 
ceivers, because the noises caused by these re- 
ceivers are identical electrically to the noises 
emanating from the broadcasting station 
which you are trying to listen to when disturbed 
by them. Everyone is familiar probably with 
the sound phenomenon known as beats. We 
know it best perhaps in organ music. If one 
organ pipe is sending out 300 pulsations a 
second, and another 340, the two will alter- 
nately add and detract from one another forty 
times a second, and you will hear, apart from 
the notes of the two pipes, a 40 "cycle" note. 
A broadcasting station operates on very much 
the same principle. For instance, we will 
say that the station is operating on 300 meters. 
When the transmitter is running and the studio 
is quiet, a million cycles a second will be sent 
out in the ether. When then a soprano sings 
a fairly high note into the microphone, the 
station continues to send out its million-cycle 
wave, and in addition to this "carrier wave" 
two waves called "side bands," one at a mil- 

lion plus a thousand 

cycles, and the other 
at a million minus a 
thousand cycles which 
when they arrive at 
your detector produce 
a thousand impulses a 
second combined with 
the carrier wave; and 
you hear these thou- 
sand pulses or the 
note which the so- 
prano is singing. If 
a single-circuit oscil 
lating receiver down 
the block is hunting 



4 8 



Radio Broadcast 



for that station, and oscillates at a million 
plus or minus a thousand cycles, it sends 
out a wave identical to one of the two side 
bands produced at the broadcasting station 
by the soprano. This, combined with the 
carrier wave of the broadcasting station, 
produces exactly the same result in your 
receiving set as the carrier wave plus the station 
side band. The detector would have to have 
a brain to be allowed to conclude that no so- 
prano would be allowed to hold this squeal 
for such a long period, or that the squeal did 
not belong to the air being sung, and to cut 
it out. A brain, of course, is something that 
no mechanical or electrical device can possibly 
have. 

LEGISLATION ISN'T THE ANSWER 

I DO not believe legislation against this re- 
ceiver or circuit is the answer. We are too 
prone in this country to feel that all that is 
necessary to remedy any situation is to pass a 
law "regulating" it. It would be easy, of 
course, to prohibit the manufacture of radiat- 
ing receivers by the reputable companies en- 



gaged in the business, but 1 believe that fully 
70 per cent, of the offending receivers in use 
to-day are of home manufacture. Herein the 
difficulty lies, for though the single-circuit 
regenerator is very unselective and usually 
unable to respond to anything but the loudest 
signal present, it will certainly give the great- 
est distance and volume at the minimum ex- 
penditure of time and money. Almost every- 
one knows how to make this apparatus, and 
it seems to me that it would require a tre- 
mendous enforcement personnel to prevent 
its home manufacture and use. 

It would be hard to use the radio compass on 
the intermittent noises they produce. Owing 
to the fact that these sets are almost as ef- 
ficient on a poor antenna as on a good one, a 
moderate sized indoor antenna can be used 
with perfect satisfaction, which makes them 
difficult to find. It is impossible to search 
private houses without a warrant, and at 
least moderate grounds for search must be 
at hand to obtain a warrant. It would be im- 
possible, or at least extremely difficult, to teach 
through any educational campaign the users 




THE "WORKS" 

Showing the excellent construction of -the sensitive, non-radiating receiver designed hy Mr. \Vashington 



Regeneration Without the Squeal 



49 




THE FRONT PANEL VIEW OF THE SET 
But two controls are generally used in tuning 



of these receivers how to operate them in such 
a manner as not to produce interference with 
their neighbors; because this form of opera- 
tion would mean a careful and painstaking use 
of both hands in keeping the regeneration con- 
trol at all times just below the oscillating point 
while the wavelength control was operated up 
and down the scale in searching for distant 
stations. A much simpler method of finding 
distant stations, and that in general use, is to 
cause the receiver to oscillate and move the 
wavelength control until the operator hears 
a loud squeal. Incidentally your neighbors and 
perhaps erstwhile friends hear it, too, worse 
luck. 

AN AGGRESSIVE PUBLIC OPINION IS THE ANSWER 

THE only possible solution, to my mind, is 
so to indoctrinate the public, through mag- 
azines, newspapers and broadcasting station 
publicity, in the harm that this type of re- 
ceiver does, and in the selfishness, unconscious 
or otherwise, of its owner, that public opinion 
and a sense of fair play will rule them out of 
existence. 

Users of these receivers should also be made 
to realize that on account of the inability of 
this type to select anything but local broad- 
casting when near-by stations are running, 
the owners are missing a great deal of the real 
enjoyment of radio, i. e., being able to select 
almost any program at nearly any time. 

To the average reader, it may seem that my 
convictions in this matter are rather extreme. 
But, I certainly believe that the "transmit- 



ting" evil, if allowed to continue, will result 
in less interest in broadcasting as well as agi- 
tation for legislative action. 

1 think it is generally admitted that the 
millions of squeals sent out onto the air every 
night will, in time, lessen the enthusiasm of 
the listener-in. When the listener-in begins 
to become disinterested, broadcasting will 
slacken. Naturally either of two things must 
result the squeals must decrease or broad- 
casting will. 

We who are so vitally interested in radio 
by "we" I mean the general public cannot 
afford to see radio slump, and we will not allow 
it to slump. Radio is already a necessary and 
solid institution. The American people never 
have and never will do without something it 
likes, merely because of difficulties. Therefore, 
I do not hesitate to predict that the "trans- 
mitting" receiver will perhaps this year be- 
come obsolete. 

The trouble is not with regeneration as a 
principle, in fact it is an extremely useful 
principle, increasing the effectiveness of the 
vacuum tube enormously. Regeneration ap- 
plied with extreme care and with very delicate 
apparatus in the laboratory can make response 
from all signals weak and strong practically 
equal. The trouble is that all conventional 
single-circuit regenerative receivers, and to 
a considerably lesser degree the two-circuit 
type, can transmit because the tube which 
in these circuits is directly connected or 
coupled to the antenna, may be made to 
oscillate. 



Radio Broadcast 



HOW DESIGNERS HAVE AVOIDED REGENERATION 

THE neutrodyne was probably the first 
adequately sensitive receiver which did 
not to a greater or less degree transmit, but 
the neutrodyne, as no regeneration is em- 
ployed, is somewhat wasteful on tubes. By 
this, 1 mean that a five-tube neutrodyne does 
not get anything like the volume from its 
five tubes that it would, if regeneration could 
be employed in the three radio-frequency tubes. 

Regeneration is also a tremendous aid to 
selectivity. It can be regarded as an ap- 
plication of negative resistance. As regenera- 
tion is increased, the effective resistance of the 
circuit becomes less and less until it reaches 
zero. If pushed to, or beyond, this point, 
oscillation occurs. 

You all know that a low resistance circuit 
is a "sharp" or selective circuit. The neu- 
trodyne owes its selectivity not to the individ- 
ual selectivity of each circuit, but to what is 
called the concomitant selectivity of the three 
circuits involved. For instance, if each circuit 
reduces interference to 10 per cent, it will be 
10 per cent, in the first circuit, i per cent, in 
the second and ,V of i per cent, in the third. 
Approximately the same selectivity can be 
obtained in fewer circuits by making them of 
lower effective resistance by using regenera- 
tion. 

There are several types of receivers which 



manufacturers have developed to escape re- 
generation. The Teledyne, which is illus- 
trated in the accompanying photographs is a 
recent contribution in this line. The Teledyne 
makes use of full regeneration in the detector, 
but even if the detector is allowed to oscillate, 
these oscillations cannot be radiated because 
of the peculiar type of radio-frequency am- 
plifier ahead of the detector. The Teledyne 
with four tubes under equal conditions seems 
to have somewhat more volume than the five 
tube neutrodyne. 

The grid and filament of this radio-frequency 
amplifier are connected in the usual manner 
across the antenna tuning inductance. The 
plate of this tube is coupled to the detector- 
grid inductance, which is tuned with the usual 
parallel condenser. The detector is furnished 
with a conventional regeneration coil com- 
monly called a "tickler." The coupling be- 
tween these two tubes is such that when the 
detector-grid circuit is resonant, this circuit 
has an impedance approximately equal to the 
output impedance of the amplifier tube, which 
is the correct load for most efficient output of 
this tube. In this coupling position, the im- 
pedance is not of the correct inductive value 
to produce oscillations, so that the radio- 
frequency amplifier cannot itself oscillate. 
Its grid inductance, which is in the antenna, is 
at zero coupling position to the detector-grid 
inductance (primarily to prevent parasitic feed- 




COMPLETE CIRCUIT DIAGRAM OF THE TELEDYNE RECEIVER 
It uses one stage of radio-, two stages of audio-frequency amplification, and detector 



"As It Was in the Beginning" 



back) and therefore oscillations in the de- 
tector can never reach the antenna. 

Among the advantages of this circuit may 
be mentioned ease of handling, as there are 
only two major controls, one for each hand. 
The detector regeneration control may be left 
at a low value and used to increase the inten- 
sity after the signal has been found. If search- 
ing for an unknown station, the detector may 
be made to oscillate freely, and the primary 



and secondary controls manipulated until a 
so-called "carrier wave whistle" is picked up, 
much as in the present regenerative receiver, 
without fear of causing annoyance to your 
neighbor. It will be found to have high 
selectivity and extremely high efficiency. It 
can be used effectively on a small antenna and 
has, I think, to a greater degree, all the ad- 
vantages of the conventional regenerative re- 
ceiver and none of its disadvantages. 



"As It Was in the Beginning" 

A Personal Narrative of the Early Days of Wireless by One of the Few Men Who 
were Helping Start the Wheels Almost Before There Were the Necessary Tracks 

By ROBERT H. MARRIOTT 

Past President, Institute of Radio Engineers, Expert Radio Aide, Puget Sound Navy Yard, Washington 



I AM going to try to tell the story of how 
radio began in the United States. It will 
not be the story of who invented radio. 
That question of who invented radio is a 
subject that people quarrel over. While 
1 am not a Quaker, my ancestors in Maryland 
may have been Quakers two hundred or more 
years ago, and I may have a " hang over" from 
them that makes me desire to avoid quarrels. 
At any rate I am not going to claim that 1 or 
any body else invented anything, but just try 
to tell how and when regular everyday wire- 
less service started in the United States. I 
will call it "Wireless" because that is the name 
it went by in those days. And I am going to 
tell the story in a personal style because, in 
many ways, it is a personal story. 

I suppose the reader wants to know just why 
1 should write about this. Perhaps 1 shouldn't, 
but the reason I am 
writing about it is 
that I designed and 
supervised the con- 
struction of the in- 
strumentsand stations 
that gave the first reg- 
ular ordinary every- 
day radio service in 
our United States. 

The next questions 
are: How did I hap- 



Pioneers Three 

Are Mr. Marriott, Mr. G. W '. Pickard, and 
Dr. De Forest in radio. They are some of the 
few who started in the field who are still active, 
twenty-four years after. Here is a well-told 
story of personal experience in the days when 
the infant radio daily astounded the natives, of 
whom, most scoffed and few believed. It's a good 
story. THE EDITOR 



pen to do that and what circumstances led up 
to it? When I entered Ohio State University in 
1897, 1 had decided that I wanted to specialize 
in physics, especially on " cold light," " X-ray, " 
or "Wireless." The head professor of physics, 
Dr. Thomas, was just recovering, after several 
months, from being burned by X-rays, which 
was discouraging for " X-rays," and he told me 
he did not think "cold light" was a field that 
we could do much with, so 1 decided on "wire- 
less." 

Dr. Thomas, was a scientist and he tried to 
see that 1 applied myself correctly to the study 
of what had been written and to the perform- 
ance of the experiments, which had led up to 
wireless as it was then. Gradually this 
worked up to a point where I had quite a col- 
lection of wireless apparatus that 1 experi- 
mented with or, one might frankly, say 

"played with." As no 
other student was suf- 
ficiently impressed by 
wireless to work with 
me, I had to control 
both the transmitters 
and receivers by my- 
self, therefore the 
longer distance work 
about the campus was 
accomplished by fixing 
a clock pendulum so 



Radio Broadcast 



it would touch a pool of mercury closing a 
circuit and making the transmitter send a dot 
every second. 

THE EARLIEST RADIO COMPANY 

IN 1901, articles appeared in newspapers stat- 
ing that a corporation called the American 
Wireless Telephone and Telegraph Company 
was starting into wireless on a commercial 
scale. That company based its right to exist 
on a wireless patent issued to Professor Dol- 
bear in 1886. I wrote the company asking for 
a job. Much to my surprise, the president of 
the company wrote back and told me I could 
have a job if I would take it at once. 1 
hadn't quite finished my college course but 1 
took the job, in June, 1901. 

We of the American Wireless Telephone and 
Telegraph Co., built stations at Galilee, Briele 



and Barnegat, New Jersey, and placed a station 
on a vessel to report the yacht races of the 
Columbia and Shamrock in the fall of 1901. 

Three organizations tried to report those 
yacht races, Marconi representatives from Eng- 
land, De Forest who was starting a wireless 
company in New Jersey, and our company, the 
American Wireless Telephone and Telegraph 
Company. Mr. Greenleaf Whittier Pickard 
was also with the American Company. I be- 
lieve that Dr. De Forest, Mr. Pickard, and I 
are the only Americans who have continued 
actively in wireless up to the present. The 
others, who are living, have entered other 
lines of work or have retired. 

Except for the brief service rendered in re- 
porting the yacht races, those stations only 
served for demonstrating and experimenting 
as other stations had done before. They were 




RADIO PIONEERS TWENTY-FOUR YEARS AGO 

The men who built the wireless apparatus during the winter of 1901 and 1902 in the shop of the Carstarphen Electric Co.. 
Denver Colorado. Mr. W. P. Carstarphen is the tall bald man in the rear. Mr. G. T. Swenson who later became Mr. 
Marriott's assistant in the California work is the man in the checked shirt in the center. Mr. Marriott is at the 1< 
with his hand in his pocket. He says he was trying to raise a beard to look old enough for his job. 



"As It Was in the Beginning" 



53 




RECEIVING APPARATUS, MODEL IQO2 

The coherer detector, decoherer, relays, sounder, tuning transformer, and tape recorder are shown on the large board. 
At the right is shown a contact type detector with telephone receivers. In this contact detector, steel balls floating on 
mercury were brought into contact with a strip of aluminum or oxidized iron. The contact pressure was varied by screw- 
ing a thumb screw in or out of the mercury. The phones used were the adjustable-magnets, watch-case type of Stromberg- 
Carlson phones, rewound with fine wire (36 or 40 B&S). Note the leveling screws on the coherer receiver board; not only 
were these necessary but the coherers had to be very carefully made, exhausted by a mercury pump and the circuits 
screened by a metal case as we screen circuits now. Taken in Denver, March, 1902 



not located where there was a demand for the 
kind of service they could render. One of the 
main things they demonstrated was that wire- 
less stations should be placed where there was 
a demand for what they could do, if wireless 
was to develop as an art. Also those three 
companies produced the first prominent wire- 
less interference object lesson, when they in- 
tentionally and unintentionally interfered with 
each other in their efforts to each beat the 
other at reporting the yacht races. 

About the time of these races, rumors started 
in the American Wireless Telephone and Tele- 
graph Company that those who were working 
for. the American Company would get op- 
portunities to become chief engineers of sub- 
sidiary companies. According to the story, 
the promoters of the American Company had 
formed that company as a parent company 
and had parcelled out the United States and its 
possessions to a number of subsidiary organi- 
zations. The understanding was that the par- 
ent company was to furnish patent protection 
and instruments for considerations, and trained 
men for the subsidiary groups to hire as chief 
engineers. 



By the subsidiary arrangement, the Pacific 
Wireless Telephone and Telegraph Company 
and the Continental Wireless Telephone and 
Telegraph Company had the Western States, 
Pacific States, and Alaska. Practically, they 
were one company because the two companies 
had the same men for officers. They seemed 
to me to have a territory where wireless might 
be immediately useful. After a few weeks of 
talks, telegrams, and letters while 1 was super- 
vising the building of a station at Barnegat, 
New Jersey, I joined to the Pacific and Con- 
tinental Wireless Telephone and Telegraph 
Companies and went to their headquarters in 
Denver. 

The parent company had not lived up to its 
agreement to supply instruments, and from 
what I had seen of the officers of the parent 
company I did not believe they would ever 
supply the apparatus; so 1 set out to build two 
sets of instruments for use between Catalina 
Island, California, and the mainland of Cali- 
fornia. Some of the officers of the Pacific 
and Continental companies wanted to put the 
stations at Denver and Golden, Colorado, 
where they would have been, simply, another 



54 



Radio Broadcast 



case of experimental or demonstration stations 
and moreover they would have been in com- 
petition with both wire telegraph and wire 
telephone. I believe those officers never did 
agree to the California plan, however, as the 



BIRD S EYE SKETCH OF CATALINA AND 



THE ADJACENT MAINLAND OF CALIFORNIA 




saying is now "We got away with" the Cali- 
fornia plan. 

Work on the wireless instruments was started 
in November, 1901, in a little Denver shop be- 
longing to Messrs. Carstarphen and Wallace. 
By the first of the year 1902, Mr. W. P. Car- 
starphen had interested capital, moved to a 



larger place, and changed the name to the Car- 
starphen Electric Co. I furnished the designs 
and supervision and the employees of those 
companies built the apparatus. 

WHAT APPARATUS WE HAD 

THE induction coil, vibrating interrupters, 
and the coherer detectors used in wireless 
sets in those days were not so bad for demon- 
stration purposes, but they were obviously un- 
reliable for giving public telegraph service. 
The vibrators would stick and stop. The co- 
herers wouldn't work when they should, and 
would work overtime when they shouldn't, and 
the tape recorder made the same dots for 
static that it made for signals. So I designed 
an interrupter consisting of a motor driven 
disc with two insulating segments and two 
brushes pressing against it. That interrupter 
was effective and more reliable. We built 
coherer receivers, but in the meantime I built 
and tried out numerous contact point detec- 
tors with telephone receivers for sound re- 
ception. In those receivers static did not 
make the same sound that signals made. I 
bought watch case receivers like the " Hello 
girls" wore, rewound them with fine wire and 
mounted two on one head band like head sets 
of to-day. 

I hired one of Mr. Carstarphen's men, Mr. 
G. T. Swenson. as an assistant and in April, 
1902, we took the completed instruments to 
California and started construction of a station 
above Avalon on the Island and another at 
White's Point on the mainland near San Pedro 
and about twenty-five miles from Avalon. 
White's Point was the nearest point and located 
there was a dance pavilion which we made into 
a station. At Avalon we had to blast off part 
of the hill and build a station house. 

THE FIRST STATION 

A REAL, practical and continuous demand 
existed for telegraphic communication 
between Avalon, Santa Catalina Island, and the 
mainland of California. The demand for a 
service that would be more suitable than car- 
rier pigeons and two or three daily boats had 
existed for some time and the needs for such 
service were growing. Not only was the de- 
mand there but the interfering static was 
more pacific on that coast than on the Atlantic 
Coast of the United States, and the distance 
was short enough for day-and-night, all-the- 
year wireless service. In addition to those 



"As It Was in the Beginning" 



helpful conditions, the wireless apparatus we 
installed was simple. That apparatus did not 
contain the erratic coherer or induction coil 
vibrator and any part or material in it could 
be bought in the open markets of the United 
States and repairs could be made by almost 
any studious electrician. Those are probably 
the main reasons why wireless became a suc- 
cessful everyday public service between Cata- 
lina and the mainland. 

Wireless operators did not exist in those 
days. There were plenty who could receive 
the signals made by a 
wire telegraph sounder 
or read the tape marks 
as produced with the 
coherer type of wire- 
less receiver, but they 
had not learned to rec- 
ognize the same dots 
and dashes in the form 
of short and long buz- 
zes in telephone re- 
ceivers. The first few 
messages were sent 
and received by Mr. 
Swenson and me al- 
though neither of us 
were operators. To 
send, we picked the 
letters out of a printed 
American Morse code, 
and to receive we 
made a mark with 
a pencil when we 
heard a short buzz 
and other marks or 

left spaces in proportion to the length of 
buzzes and spaces and when the sending 
stopped we compared those marks to a copy 
of the Morse code and wrote the correspond- 
ing letters above the combinations of dots 
and dashes. Many of the subsequent mes- 
sages were received in almost that painfully 
slow way until real operators retrained their 
minds to give the same translation to buzzes 
that they had been giving to sounder clicks. 
After a few operators had set the example, 
others lost the it-can't-be-done feeling, and 
learned to receive rapidly. 

The transmitter dynamo was driven by a 
gasoline engine having a spark ignition system 
and those sparks interfered with receiving. 
Sometimes, the gas engine had to be stopped 
to receive. Shutting down to receive and 




AN HISTORIC RADIO GROUP 

R. H. Marriott driving the first nail in the first wireless 

station at Avalon, Santa Catalina Island, May I2th, 

1902. This was the first regular everyday wireless 

service station in the United States 



starting up the temperamental gas engine to 
transmit, combined with detector adjusting 
and undeveloped receiving ability made the 
early service very slow as compared to a good 
wire line. 

WHEN THE TROUBLE STARTED 

THE majority of the public that paid any 
attention to our efforts during the building 
and testing of the stations, seemed to be divided 
in its opinions_of wireless experts. They 
seemed to think the wireless experts were 

supernatural, crazy, 
or crooked. These 
three classes of opin- 
ions manifested them- 
selves in ways which 
were sometimes amus- 
ing and sometimes 
painful to the expert. 
Where the opinion 
overrated us, it some- 
times caused some 
embarrassment. For 
example, while we 
were developing the 
sound receiving 
method, a number of 
sensitive microphones 
had been made and 
the Avalon station 
had been provided 
with concrete piers 
anchored in rock, and 
a sound proof booth, 
for delicate micro- 
phonic work. Before 

the station was completed, a visitor asked 
some question about a carbon-steel micro- 
phone that was resting on a piece of paper 
on a pier and while the microphone was be- 
ing explained and demonstrated, the visitor 
wore the telephone receivers attached to it 
and a fly lit on the paper and walked. The 
visitor saw and heard the fly light and 
heard his foot steps in the telephone re- 
ceiver. The visitor was startled and amazed 
almost to the point of dragging the microphone 
off of the pier. And I was equally startled 
and amazed the next day when 1 read of my- 
self as a scientific wizard of infinite ability 
occupied on the hill above Avalon with instru- 
ments so sensitive that 1 could hear flies walk 
in San Pedro. As the distance was twenty 
five miles, that was an excellent yarn for those 



Radio Broadcast 



days although it could be done with radio- 
phones and receivers of to-day. 

At Catalina was a resident who had known 
and admired my grandfather. He had ad- 
mired my grandfather so much that he did not 
want to see the family name dragged in the mire 
by me. From his remarks I gathered that he 
with others were convinced that wireless was 
all a fake and he was very much afraid that 
my notably honest and wise grandfather had 
failed to leave one or both of those notable 
characteristics to this grandson. He was 
sincere even to the extent of intimating he 
would pay my fare out of the country if 1 was 
as weak in my finances as I appeared to be 
weak in honesty or wisdom. 

The 1902 Fourth of July fireworks at 
Avalon were novel in that they included the 
burning of a steamship. The old S. S. Hermosa 
which had served Avalon for years, with trans- 
portation and communication, was set on fire 
and towed around and back and forth in the 
outer harbor while the band played and rockets 
ascended from the top of Sugar Loaf Rock, 
and the wireless 
station contributed 
an illuminated star 
at the top of the 
wireless mast on 
the hill above Sugar 
Loaf. The star was 
made as big and 
bright as we could 
make it by using all 
the electric power 
our dynamo would 




WHAT THE PAPERS PRINTED 

A clipping from the Los Angeles Herald of August 

3rd, 1902 showing photos of the White's Point Station 

and some of the messages exchanged during the test 

made by the Los Angeles Herald 



deliver. That noticeable brilliancy on our part 
had an unexpected effect. 

THE FIRST PACIFIC COAST MESSAGE 

ON JULY ninth I received the first mes- 
sage at Avalon and all it said was " Do 
you get me." It was answered in the affirma- 
tive, but the answer was not received. Mr. 
Swenson on the mainland had started sending 
signals to me on June 28th; however, in trying 
out the various receivers I had not tried to 
translate what he said, if he did say anything, 
until 1 picked the kind of detector that seemed 
to be the most serviceable. That detector 
proved to be a contact between a polished steel 
tip and an oxidized iron plate. The first plate 
I made was from a hack saw blade, but I 
found I could do better by burning the surface 
off a piece of tin can using a blow torch and a 
little water and then a little oil on the oxidized 
surface. To get fine adjustment I needed a 
well made steady screw with fine threads and 
a large dial. The spherometers 1 had used in 
college to measure the curvature of lenses were 
the first thing 1 thought of, 
so 1 went to Los Angeles 
and bought some and Mr. 
Swenson made them into 
detectors that were used 
for several years. 

Adjustments at the two 
stations followed and the 
exchanging of test messages 
began. The statement that 
test messages were being 
exchanged brought forth a 
chorus from "Doubting 
Thomas." A few days later 
Jeffries and Fitzsimmons 
fought in San Francisco 
and as we wanted early 
returns and wanted to con- 
vince doubters, we arranged 
t'o wireless the returns 
across to Avalon. 

"EARS THEY HAVE AND 
HEAR NOT" 

THE fight returns were 
laboriously received by 
me on the hill above Avalon 
about midnight and written 
out and taken down to 
town and posted. Those 
who were up read the 



"As It Was in the Beginning' 



57 



bulletin but did not seem to be inclined to 
pay any bets on the strength of what it said. 
However, 1 was happy because 1 knew the 
papers would verify my report next day. But 
I had not studied psychology sufficiently for 
that situation. The verification by the news- 
papers resulted in a large collection of stories 
as to how the news had been received, in every 
way but by wireless. The knocking was epi- 
demic, for nearly everybody broke out with 
verbal hammers. Carrier pigeons were cred- 
ited with the feat, a man was said to have been 
seen bringing me the message in a small boat, 
good guessing and advance information were 
discoursed upon and then somebody bobbed up 
with the story that the ex-Fourth of July star il- 
lumination had been used on the mainland sta- 
tion mast and somebody had seen the flashing 
light. That yarn about the star was damnable. 
The gossip and atmosphere of disbelief in 
the wireless was enough. However it had not 
stopped at that but was reflected somewhat in 
the more durable black and white of the news- 
papers. Catalina was advertized as a place 
where one could get scenery, climate, fish, and 
goats. 1 enjoyed the scenery, climate, fish, 
and hospitality of the Banning brothers who 
owned the Island, but lost my goat to the 
doubting public and similar newspapers. The 
Los Angeles Times was one of my goat getters. 

"AND EYES, BUT SEE NOT" 

THE Los Angeles Herald had been friendly 
and was asked to send men to both sta- 
tions and exchange messages and tell the public 
what it found. On August second when the 
Herald notified me at Avalon that they were 
on the job at the mainland stations, I was tired 
and sore from the effects of oral and newspaper 
gossip so my message to the Herald was " Rip 
and Roast the Times for us." The Herald 
replied "We Will" and patiently sent and re- 
ceived messages over the comparatively slow 
system and wrote up their work and published 
it, including my message. 

A daughter of a wealthy man was taken sick 
at Avalon and her mother obtained a specialist 
from Los Angeles by using the wireless. Those 
successive demonstrations helped to get more 
people to believe wireless could give service, 
but the thing that removed all doubts from 
everybody's mind was as funny as it was 
thorough. Two colored men got into the 
Metropole Hotel Bar on the Island and col- 
lected some change, a case of champagne and 



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HOW THE NEWS GOT FROM THEM TO US 

First page of The Wireless Vol. I No. i. A little news- 
paper started by the Los Angeles Times, March 23, 1903. 
It was made up from wireless dispatches received from 
the California mainland 



some miscellaneous drinkables and departed 
from Avalon with the loot on the five A. M. 
boat. Such a get-away was old and had been 
safe for years because there had been no means 
of communication and the next boat did not go 
until eleven A. M. But the Bar folks knew 
the wireless would work and they sent a wire- 
less message to the mainland which caused the 
colored men to be very surprisingly and very 
officially received at the pier in San Pedro. It 
was a spirited wireless comedy for everybody 
but the Negroes and it caused a laugh which 
shook almost all remaining stubborn disbelief 
out of the public. 

SO WIRELESS BEGAN FOR US IN IQO2 

THAT business of putting wireless into com- 
mon everyday service in the United States 
occurred in 1902 or ten years after Sir William 



Radio Broadcast 



Crookes had said " Here, then, is revealed the 
bewildering possibility of telegraph without 
wires, posts, cables, or any of our present costly 
appliances." (Fortnightly Review, London: 
February, 1892.) He said those words while 
discussing the wireless experiments which 
Hertz had performed in 1886. 

After the stations proved themselves, the 
newspaper reporters and others said they had 
not intended to belittle wireless and wireless 
apparatus or wireless engineers, but that they 
may have unconsciously done so in attacking 
the stock jobbers who were exaggerating what 
wireless could do so they might draw big 
commissions from the sale of doubtful stock. 

Several wireless companies were 

selling stock and had been selling 
stock by saying or implying that 
they were about to span the oceans 
and continents and take all the bus- 
iness away from the telephone, tele- 
graph, and cable companies. Stock 
salesmen were not telling the truth 
when they said the wireless of those 
days could render everyday service across the 
Atlantic or Pacific or could compete with wire 
lines. Antidote statements were a natural 
result, but they were equally untruthful when 
they had said that the wireless we had was not 
capable of giving everyday useful service across 
that twenty-five miles of ocean where there 
was no cable to compete with. 

After a few months of everyday wireless 
service, the Los Angeles Times started a little 
paper called "The Wireless" at Avalon. The 
contents of that paper consisted of local news 
and world news as received via wireless. 

HOW THE AVALON CIRCUIT PROGRESSED 

SINCE that time, several different organi- 
zations have owned and operated and 
improved that wireless circuit from the main- 
land to the Island. During those years the 
island station was shifted about Avalon and the 
mainland station was shifted about San 
Pedro, Los Angeles, and Long Beach. The 
list of owners included the Pacific Wireless 
Telephone and Telegraph Company, the United 
Wireless Telegraph Company, the Marconi 
Wireless Telegraph Company of America, the 
U. S. Navy, and the Pacific Telephone and 
Telegraph Company. 

The Pacific Telephone and Telegraph Com- 
pany in late years (1920) made that radio cir- 
cuit one which could be used for either tele- 




phoning or telegraphing and they connected 
the mainland radio station through repeaters 
to the whole Bell Telephone System of the 
United States and they built a local Bell system 
on the island to serve as an inlet and outlet 
for the Catalina radio station. Avalon citizens 
were able to talk by wire to the Catalina radio 
station and thence by wireless to the mainland 
and thence by wire to Los Angeles, San Fran- 
cisco, Chicago or New York. And for the 
purposes of further demonstration, Deal Beach 
on the New Jersey shore and the S. S. Gloucester 
on the Atlantic were equipped with radio 
phones and conversations were carried on via 
wire and wireless between Avalon and the 

Gloucester. 

After the telephone service be- 
came a matter of course, many of 
the Telephone Company's custom- 
ers talked fluently and freely, not 
realizing that they were operating 
a radio telephone circuit between 
Catalina and the mainland, and a 
growing number of radio opera- 
tors, amateurs, and broadcast listeners tuned-in 
to pick up what was said over that radio tele- 
phone circuit. Some of those who used that 
radio telephone circuit were movie actors and 
people with no work to do, but with time, 
money, and energy to spend, therefore it is not 
difficult to imagine their conversations as pos- 
sessing sufficiently interesting possibilities to 
tune-in for. To provide secrecy, the telephone 
company tried experiments at making the 
radio waves such that only their receivers were 
capable of changing the scrambled radio waves 
into intelligible speech. By this method, the 
telephone company might have kept the 
speech unintelligible to all but experts and 
ingenious amateurs, but there were other inter- 
fering factors. When the original radio circuit 
started in 1902 there were no other radio re- 
ceivers or transmitters to interfere with it. 
As time went on, radio service circuits mul- 
tiplied and produced interference, from trans- 
mitters and regenerative receivers. 

"THE BOY GREW OLDER" 

THE wireless service family had grown in 
twenty-one years to include service be- 
tween land stations, ship stations, ships and 
shore, submarines, airships, aeroplanes and 
amateur stations and service from compass 
stations, fog beacon stations and broadcasting 
stations and besides that, the radio frequencies 



"As It Was in the Beginning" 



and radio apparatus that had been developed 
for radio service had also been applied for 
communication over telephone, telegraph, and 
high and low voltage power lines. From serv- 
ing dozens it had grown to serve millions. 

The telephone company could not entirely 
avoid all of the interference even though they 
did carefully choose the sites for their stations 
and use loops, wave-traps and other selective 
devices. Such interferences to the wireless 
telegraph circuits had only been a handicap 
and irritation for the wireless company's op- 
erators, but in the radio telephone it handi- 
capped and irritated the customers. And last 
of all and probably greatest of all, the wave- 



lengths used by the telephone company were 
wanted for radio broadcasting. 

That first wireless service circuit lived and 
served the public for twenty-one years. But 
the wireless circuit family had grown so large 
there is no longer any room for that first cir- 
cuit. The Pacific Telephone and Telegraph 
Company substituted two cables for it when 
their radio station licenses expired on August 
i, 1923, and quit using the wireless. The 
argument for doing this was that the cables 
provide more secrecy, no interference, and 
connect up better with the wire system and 
business system of the Pacific Telephone and 
Telegraph Company. 



Spoken Literature for Use on the Radio 

By FILSON YOUNG, London 



THE literary possibilities of broadcasting seem 
not to have been realized yet either in England 
or America. Broadcasting in England began 
in 1920, and to-day there are something like 500,000 
known users of wireless in this country, which with 
its dense population and large towns dotted over the 
country at close intervals is particularly suitable for 
a broadcasting covering the whole country. At 
present the entertainment provided by the British 
Broadcasting Company between the hours of 3:30 
in the afternoon and 10.30 at night covers an im- 
mense variety; short talks on various non-contro- 
versial topics; first class symphony concerts, ser- 
mons, services, speeches and so forth, as well as 
hours specially devoted to children's and women's 
interests. But on the purely literary side the re- 
sources suggested by it have as yet hardly been 
tapped. Once a week indeed there is a "literary 
talk" of a few minutes, during which certain new 
books are referred to; a book of my own had the 
honor of being among the first thus to receive a 
broadcast review, and the effect was startling. 

But just consider the possibilities attaching to 
the extended and imaginative use of this new and 
wonderful medium. The written word, although it 
remains, is always inferior to the spoken word in 
its actual power and moving influence, Things 
uttered with the living voice have an appeal and 
command an attention which in many cases would 
never have been achieved at all by the written word. 
At present the newspaper element of broadcasting 
is represented by brief summaries of news, weather 
reports and so forth; but why should brief original 
composition, specially designed for this end, not be 
added to the utterance of broadcasting? A little 
five-minute essay, spoken in his own voice by a well 
known author would have a charm and fascination 
for people that has evidently not yet been realized. 



There is no reason, moreover, why leading articles 
which are after all only brief essays in the expression 
of definite opinions should not form part of the 
wireless repertoire; there is no reason why the 
expression of opinion, as represented by the old 
fashioned leading article, should not take a new 
lease of life and exert a renewed influence. 

The ordinary person who reads a newspaper sel- 
dom occupies more than half an- hour over it. It 
ought to be possible to compile a kind of miniature 
compendium for the purpose of broadcasting, which 
would represent the picked selection which the or- 
dinary reader makes from a newspaper. Yet, in- 
stead of being read from small type printed on in- 
different paper, it would be, so to speak, performed 
like an opera; the individual quality of each writer 
would be reflected in the tones of his voice. 

Of course it is not every good writer who has a 
good voice; on the contrary, I think it is supposed 
to be the rule that distinguished writers are bad 
public speakers. That does not mean so much that 
they cannot read aloud well, as that their thoughts 
are marshaled and molded in the form of literature 
rather than of speech; the redundancies and repeti- 
tions and dilutions which make oratory effective 
are entirely foreign to the spirit of literature, which 
is compact, concise, and condensed. That is all the 
more reason why what we may call spoken literature 
is so suitable for broadcasting, where time is of im- 
portance and concentration is of the essence of the 
program. To produce an effect and a result in a 
brief utterance is infinitely more within the power 
of literature than it is of oratory. In America par- 
ticularly, I should expect this gift to be developed and 
if American broadcasting is as it is in England I shall 
expect to hear of a development of my idea before 
long across the Atlantic. 
(Reprinted by Courtesy of New York Times Book Review.) 




THE GERMAN RADIO CLUB 

Meeting in Berlin in the General Post Office with Dr. Bredow, chief 
of the telegraph, telephone, and broadcasting services in the chair 



What German Listeners-In are Up 

Against 

A Berlin Amateur's Story of What Government Restriction, 
High Prices, and Poor Apparatus are Doing for Broadcasting 



By KURT HILDESHEIMER 




E ARE up against the wall 
here in Germany. No 
amount of cussing helps. 
You can't get this and you 
can't get that, and when you 
do get something, it is poor stuff. An insulator 
is nothing but baked mud, taps come off, parts 
don't fitf and then you begin to chuck the stuff 
against the wall and go to bed swearing never 
to touch any of it again. But the next night 
you are at it again, fishing around for signals. 

You have to pay about two months' total 
income to buy a decent one-bulb receiver. 
The three shops which are selling radio appara- 
tus in Berlin are handling dismantled former 
army sets. They don't know the resistance of 
the grid leaks they sell, they don't know the 
ratio of the transformers, and you can't get a 
variable condenser with a vernier anywhere. 



The amateur who wants to buy a set must 
be a German subject, or, if he is a foreigner, 
licenses will be granted only to citizens of such 
nations as reciprocate in the granting of 
licenses to Germans. He must prove his 
identity and must be more than 21 years old. 
The postal authorities have the right to refuse 
the license if they assume that the amateur will 
in any way abuse his permission to listen-in. 

This license does not make it possible for him 
to listen-in. It merely gives him official permis- 
sion to listen-in. For the license, he pays 2--, 
marks (equal to $6). This is to-day 90,000,000 
paper marks and the average wage-earner i> 
receiving 10,000,000 to 15,000,000 paper marks 
a week. The license is good for one year and 
must be renewed after that time by payment 
of the same fee. However, the Government 
does not guarantee any of its programs, 



What German Listeners-In are Up Against 



61 



nor even that there 
will be any programs. 
The license cannot be 
transferred and is 
good only with appa- 
ratus bearing the same 
number as the license. 
Only such sets, parts, 
tubes, may be used 
which are stamped 
with the stamp of the 
R..T. V. (Reichstele- 
g r a p h e n verwaltung) 

the Federal Telegraph Administration. It is 
prohibited to change anything in the set which 
might alter the wavelength. The antenna 
may have a maximum length of fifty meters. 

The sets may have ranges from 200 to 700 
meters. The sets may under no circumstances 
oscillate. The wavelength restrictions, of 
course, eliminate all sets in which tuning is 
done with honeycomb coils. Only German 
firms are permitted to sell sets. 

It is evident that all these limitations are 



This article is not of a particularly opti- 
mistic or constructive tone; it is simply the 
outburst of a radio experimenter who chafes 
under the apparently unjust restrictions that 
prevail in Germany to-day. It possesses the 
merit of frankness, however, and although 
we do not vouch' for the accuracy of the 
statements made, we believe they are sincere 
and indicate, in general, the true color of radio 
conditions beyond the Rhine. THE EDITOR. 



designed to prevent 
the amateur from 
reachingout with these 
crippled sets and try- 
ing to listen to an 
English, French, or 
Dutch program. 

It is evident that all 
this checking-up and 
controllingand license- 
issuing and stamping 
of apparatus will cut 
heavily into any profit 

which the Government might derive from the 

high fees. 
The stamping fees are in gold marks: 

For a crystal detector set . . . . 2.50 [$0.62] 

For a tube set without amplification 6.00 [$1.50] 

For a tube set with ampliation . 7.00 [$1.73] 

For a tube . . . . .... 0.50 [$0.12] 

For every added stage of amplification i.oo [$0.25! 

(The Post Office, by the way, does not guarantee 
the quality of the sets or that no patents have been 
infringed by the manufacturers!) 




LISTENING TO TIME SIGNALS 

From POZ, at Nauen, Germany, at a German radio exhibition. Broadcasting in 
Germany has not attained nearly the same popularity as in the United States 



62 



Radio Broadcast 




A GERMAN "DETECTOR AND TWO AUDIO" OUTFIT 

It is built by the Telefunken Company and is quite be- 
yond the financial reach of most German radio enthusiasts 



THE DANGER OF CONFISCATION 

WHEN you have all your material together 
and have infringed 121,567 rules and laws 
in buying your stuff, the obstacles to getting 
any use out of a set are almost prohibitive. 
Every time I receive, I climb up my antenna 
tower and string up my aerial. Then, after I 
shut down for the night (or at six o'clock the 
next morning), I go up the tower again and 
take the aerial down. It is a nice game and 
the first fifty-six years are the hardest. 

And then every night you may sit and listen 
for .broadcasting which isn't there at all. 
The nearest stations are in Paris, London, and 
the Hague. But these must have peculiar 
broadcasting hours, as I haven't been able to 
catch them yet. London is apparently too 
far off for one bulb without amplification. 
So all the fun you have is dit-dah-dit dah-dit. 
You begin to feel you are lucky at that. Of 
course, there is no checking up of wavelength 
and you can never tell where or when you can 
tune-in on anything. How is the novice ever 
to try out a circuit or to know what is wrong? 

Now that the German radio law is what it is, 
we can only groan and shed a few tears at it. 
It does not even give you a chance to fight; 
it just kills you. I am sure that in spite of all 
this, I would ultimately have been able to pick 
up English, French, and perhaps American 
programs. Now I am really expecting a raid 
every day. It is nothing short of preposterous 



the way the Government is 
killing off activities and is 
reserving radio for a few 
profiteers who can afford to 
pay any price. Besides, it 
would never appeal to me to 
have a sealed-up receiver 
without a chance to go after 
long-distance stations and 
to improve my knowledge 
of radio. 

Here a government run- 
ning the largest (at least, I 
think it is) station in the 
world (POZ, at Nauen) and 
operating directly with 
many countries on long 
wavelengths, is suppressing 
the amateur "because he 
might disturb the regular 
traffic." We don't want 
sending licenses for the 
present, only the right to experiment with this 
wonderful art. If the Government cannot code 
their messages with one of the well-known 
coding typewriters, or if they cannot use high- 
speed telegraphy, they will not be able to sup- 
press the man who really intends to exploit the 
news he hears. He can have his loop and 
high-powered set in some back room and receive 
without anyone ever finding it out. 

We amateurs would be glad to pay for an 
experimenting license, if one could be had 
within reason. We would not think of listen- 
ing to any telegraph messages. But I know 
that I am not going to the Post Office to get a 
license which would allow me to buy a set, 
because my name would then be on record, and 
I would have more trouble than fun. 

THE FIRST GERMAN RADIO CLUB 

THE Deutscher Radioklub was organized 
in Berlin in the spring of 1923. It de- 
veloped rapidly and attracted wide attention. 
Of course, the authorities frowned on the club, 
and the first series of lectures with demonstra- 
tions were followed by official summons to the 
lecturer, who was a scientist of renowned 
standing and the holder of an experimenter's 
license. He was cautioned not to use his sets 
again outside his laboratory or his license 
would be cancelled. 

The fees for members could not be fixed in 
marks on account of the upset currency situa- 
tion in Germany. At present the fees are 10 



What German Listeners-In are Up Against 



63 



times the postage on an ordinary letter as 
entrance fee, and 6 times this postage as 
monthly fee. This is to-day 10 billion and 6 
billion paper marks. 

The Radioklub ti \ ; spread information 
as well as it could through meetings, lectures, 
demonstrations, and newspaper articles. After 
some time the Post Office was no longer able to 
evade the pressure brought to bear on it from 
all sides. 

A BROADCASTING COMPANY STARTED 

AT ABOUT this time, the public was 
astonished to find that the Government 
has already been "studying the question" 
since January, 1922. A company called "Die 
Deutsche Stunde" (the German Hour) had 
been floated by the Post Office and some of the 
large firms. Experiments were started in 1923 
from the Government station, LP, in Koenigs- 
wusterhausen, also from the Telefunken station 
in Berlin and from the Lorenz station in Eber- 
swalde near Berlin. 

Broadcasting was quite irregular and chiefly 



intended to find out the best conditions under 
which the service could be finally started. It 
was during these experiments that the Govern- 
ment claims to have found out that it would 
be necessary to limit the future broadcasting 
service considerably, as it might otherwise be 
disturbed through the enormous traffic between 
all the surrounding countries. It was stated 
that the number of waves still available was 
very limited and this was one of the chief 
reasons why the amateur activities were going 
to be carefully watched. However, this state- 
ment of the Government can hardly be recon- 
ciled with the fact that the commercial traffic 
is without exception carried on with longer 
waves than would be required for the amateur 
broadcasting service. 

THE WICKED EXAMPLE OF THE U. S. 

A PARTICULARLY striking example of 
the way in which the public was misled 
was by newspaper articles about the American 
Radio Conference under Secretary Hoover. 
It was stated in these articles that the chaos 




GERMAN BROADCAST LISTENERS 

Using a receiver which is quite generally sold by one of the broadcasting companies. 
I hese receivers are sealed and can only be used over a certain band of wavelengths 



Radio Broadcast 




FOR TIME SIGNALS ONLY 

A neat German receiver, tuned exactly to the wavelength 
of POZ, Nauen. The listener has no adjusting to do. 
The diagram on the panel explains how the dots and 
dashes sent during the five-minute period indicate the 
correct time 



in the U. S. had grown so bad that nobody 
was able to pick up anythingon account of inter- 
ference but shrieks, growls, and hisses. The 
public was urged not to follow the "wicked" 
example of the U. S. and England, where no- 
body was paying fees for receiving and where 
the whole broadcasting service would soon 
break down for lack of funds, but to be a good 
boy and rely on the ever-so-well-meaning 
Government and run away and play till every- 
thing had been carefully considered. 

In October, 1923, the press was invited to 
attend the first trial demonstration in the 
Telegraphic Technical Experimental Labora- 
tory in Berlin. A concert and declamations 
were broadcast from Koenigswusterhausen. 
At the same time, the exact regulations were 
printed in a paper published exclusively for 
the German public broadcasting service, Der 
Deutsche Rundfunk (The German Broadcast- 
ing Service). This paper published the laws, 
the reasons of the Government for limiting 
the amateur activities, and in the future it will 
also publish the programs. 

The first idea of the Government was that 



this new sport was a fine field for taxation, so 
it piled it on thick and heavy. A tax is levied 
on sets and on licenses for amateurs. The 
necessity of such taxation was explained by 
the budget deficit. . A large part of the tax 
should also go toward creating so good a 
program right from the start, that people 
would not lose interest after a short time in 
the radio game, if it did not come up to their 
expectations. It was the question of who was 
going to pay for the broadcasting. Here in 
Germany i t is going to be the amateur directly. 
Of course the Government knows that only a 
comparatively small number of people will 
apply for licenses right away so they are cau- 
tioning the public not to expect too much for 
their money in the beginning. The question 
whether the manufacturers would be willing 
to bear the expenses of broadcasting has never 
been raised yet. It is certain, however, that 
they would be glad to contribute directly to 
it in order to profit by the consequent sale of 
sets and not be subject to taxation and bu- 
reaucratic control measures. 

A certain part of the fees collected from the 
amateurs goes to the Government and the 
balance to the Deutsche Stunde or other broad- 
casting organizations. 

MAKING RADIO "POPULAR" 

BROADCASTING will take place from the 
Government station in Koenigswuster- 
hausen and from the Voxhaus in Berlin. This 
is a private firm making gramophones and 
records, and while the records are being 
made in their Berlin studio, the music will be 
picked up and broadcast. Other broadcasting 
stations are planned in Munich in Bavaria 
and in Stuttgart in southern Germany. All 
will work on different wavelengths to prevent 
interference. Every station is intended to 
supply a district of 150 kilometers radius. 

At the same time the Deutsche Stunde is 
going to lease lecture rooms, concert halls, 
etc., from time to time and install portable 
receiving sets for the evening and have the 
lectures and music picked up and reproduced 
through loud speakers. This absolutely absurd 
idea is the best way of discrediting radio with 
the average German who has a highly trained 
musical ear. It would be like inviting some- 
body to attend a concert consisting of ampli- 
fied gramophone records. People coming 
for the novelty of the thing will leave the 
place with an utter disgust fof radio, when they 



What German Listeners-In are Up Against 



can listen to the best soloists, philharmonic 
orchestra, opera, etc. at slightly higher prices. 
Of course this is no way to popularize radio 
in a nation where 90 per cent, of the people 
know nothing at all of radio. 

Another regulation: it is prohibited to receive 
other than the German programs. Just im- 
agine the poor amateur when he gets tuned in 
on London dropping his headset in horror and 
ringing up the Government for instructions 
what to do, when he cannot tune it out. The 
owner is further responsible that nobody mis- 
uses the set. The government officials are 
authorized to enter and search any room in 
which radio sets are stationed just as if you were 
the vilest criminal. 

The amateur (if people with such sets could 
justly be called amateurs, I think, however, 
they had better be labeled "wireless gramo- 
phonists") is thus crippled on all sides. No 
buying of parts, building his own, experiment- 
ing with different circuits, no amplification for 
him, he is just switched on to a kind of enlarged 
gramophone which works only certain hours 
of the day. No distance work, none of the 
thrill and fascination of listening to another 
country and knowing that you are one of the 
vast and enthusiastic wide-spread audience. 

HOW THE PRESENT SYSTEM IS LIKELY TO 
WORK OUT 

THE high costs of administration and 
the small number of subscribers in the 
beginning will prevent profitable utilization of 
the returns and listeners-in abroad cannot be 
taxed either. There will not be enough ama- 
teurs willing to pay the fees, knowing that they 
will be kept on record and subject to frequent 
examination and raids on their apparatus. 



The quality of the service in the beginning will 
necessarily be poor, just when it is most es- 
sential to startle everybody with the high 
quality and frequency of the performances. 
It can be safely assumed that the enterprise 
of the manufacturers, who are eager to create 
an adequate outlet for their production and 
willing to cooperate in the broadcasting it- 
self, can not be set aside for any length of 
time. 

Of course there will always be quite a number 
of people who do not care about the technical 
part of radio. All they want is to hear the 
music and not be bothered with assembling 
the set or with technical knowledge. For these, 
the regulations may be all right if they can 
afford to pay the high fees and the high prices 
for the receiving sets. But preventing all 
persons who are not 2 1 years old and all those 
who want to experiment from going ahead 
and doing it, is preposterous. The amateur 
who wants to experiment would be willing to 
pay for a license, even more than the fee 
stipulated at present. 

However, as long as these crippling condi- 
tions prevail, Germany may as well definitely 
renounce any increase in the technical educa- 
tion and knowledge among the people, and the 
chance of any improvements or inventions 
from the ranks of the amateur. 

1 am afraid this has not been a particularly 
optimistic account of the radio situation in 
Germany. The fact is, I have looked pretty 
thoroughly without so far finding anything 
that would justify loud hoorays, or even any 
very cheerful expectations for the future. No 
one is waiting more anxiously for a good omen 
than I am; and when it appears I'll be among 
the first to join in the hymn of thanksgiving. 



JLJOIV can we speed up our trans-oceanic and trans-continental radio messages? Is a 
new code the answer? Has the limit of speed been reached? Arthur H. Lynch 
has an exclusive interview with Major-General George Owen Squier in the June RADIO 
BROADCAST in which General Squier explains a startling and well-worked-out plan which 
he says would permit, according io his figures, an increase of more than 1 50 per cent, in 
the speed of radio telegraphic, cable and telegraph traffic. 



Looking Into the Vacuum Tube 

WHAT MAKES THE WHEELS GO 'ROUND: III 

What Happens in the Vacuum Tube and How 

By WALTER VAN B. ROBERTS 

Each of these articles is a unit in itself; you can start reading now. This is the third 
article in Mr. Roberts's series. The first appeared in this magazine for March. THE 
EDITOR. 



r ^HE 

mo: 

cah 
acti 

JfL. r^tr\ 



vacuum tube is the heart of 
most radio circuits, and because of its 
calm appearance and almost uncanny 
action, many [are persuaded they 
cannot understand its fundamentals. 
Every one can see the three elements in the 
tube, called (reading, so to speak, from right 
to left), plate, filament, and grid. These ele- 
ments are insulated from each other, although 
placed quite close together. 

29. THE PLATE CIRCUIT 

REFER to Fig. 9. A wire called the filament 
is heated (in the best possible or "hard- 
est " vacuum) by means of electric current from 
the filament heating battery which is usually 
called the A battery. If heated to a tempera- 
ture sufficiently high (the necessary tempera- 
ture depending upon the kind of wire the 
filament is made of) a large number of electrons 
are emitted from the filament, like steam from 
boiling water. They are then sucked over to a 
sheet of metal called the "plate" which attracts 
them because it is kept at a potential more 
positive than that of the filament. This flow 
of electrons to the plate constitutes the plate 
current, and the battery that keeps the poten- 




FLOW OF ELECTRONS 



"B" BMTERN 



FIG. 9 
A simplified diagram showing how the vacuum tube works 



tial of the plate positive and hence maintains 
the plate current is called the plate battery or 
the B battery. Electrons leave the filament, 
are attracted through the vacuum to the plate, 
leave the vacuum tube via a wire sealed 
through the glass, traverse the B battery, re- 
enter the vacuum tube by the filament leads 
along with the filament heating current, and 
get boiled off the filament again for another 
round trip. 

30. THE GRID 

SO FAR only two electrodes have been 
mentioned, for the hot filament is con- 
sidered as only a single electrode although ac- 
tually two wires are sealed through the glass in 
order to provide a complete circuit for the heat- 
ing current. The third electrode is called the 
"grid" because it is usually in the form of a 
lot of parallel wires close together and all 
connected together. When this structure 
(which is located between the filament and the 
plate) is given a potential more negative than 
that of the filament, it repels electrons coming 
from the filament and thus offsets some of the 
attractive force due to the plate. It is a very 
important property of the tube that a small 
change in the grid potential may be as ef- 
fective in changing the plate current as a large 
change in plate potential. The voltage am- 
plification constant, \i, of a tube may be defined 
as the number of volts that must be added to 
the plate battery to compensate for making the 
grid one volt more negative. If the grid is 
made more positive than the filament, it at- 
tracts electrons so that the plate does not get 
them all. Those electrons going to the grid 
constitute a grid current and to maintain this 
current power must be supplied by the source 
that is keeping the grid positive. Inasmuch as 
the most important function of the vacuum 



Looking Into the Vacuum Tube 



67 




FIG. IO 

The essentials of a vacuum tube circuit. 
The milliammeter measures the plate current 

tube is the amplification of power, it is im- 
portant in almost every case that the grid be 
kept negative at every instant in order that, 
as nearly as possible, no power at all be re- 
quired to maintain or vary the grid potential. 
(The quantity y. does not have to be greater 
than unity in order that the tube be capable of 
amplifying power). Wherever we say that the 
grid or plate potential is so much more positive 
or more negative than the filament, we always 
refer to the most negative end of the filament, 
the latter not being an "equipotential surface" 
when the heating current is flowing through it. 

31. PLATE IMPEDANCE 

ANOTHER very important quantity is the 
ratio of a small change in plate potential 
(measured as a fraction of a volt) to the result- 
ing change in the plate current (measured as a 
fraction of an ampere). Of the various names 
given to this quantity the term "plate im- 
pedance" will be used. Except at extraordin- 



6 -5 -4 -I -2 -I +1 +2 +3 +4 
POTENTIAL OF GRID RELATIVE TO NEGATIVE END OF FILAMENT 

FIG. II 

How the plate current varies in a vacuum 
tube when the B battery is constant and 
the polarity of the grid potential is varied 



arily high frequencies the plate impedance is 
practically the same as a pure resistance, so 
that it may be equally well called the plate 
resistance, and denoted by R p . 

31. MUTUAL CONDUCTANCE 






is called the "mutual con- 



HPHE ratio 

ductance" (being the change in plate 
current per volt change in grid potential) and 
this term is coming into use as a convenient 
figure of merit for a tube. 

The quantity, [x is simply a geometrical con- 





-6 -5 -4 -1 -2 -I 



+ 2 + 3 +4 



FIG. 12 

By varying the B and C battery voltage applied to a 
vacuum tube this family of plate-current curves results 



stant, being greater the larger the wires form- 
ing the grid, the closer they are together, and 
the further they are from the plate. R p how- 
ever depends not only upon the actual geom- 
etry of the tube but also upon the copiousness 
of emission of electrons from the filament, and 
the grid and plate potentials. Hence it is 
customary to specify the value of R p for the 
filament current, grid potential, and plate po- 
tential at which the tube is supposed to be used. 
Most receiving tubes have the value of p. 
somewhere between 5 and 10 and R p about 
20,000 ohms more or less. Some tubes have 
[A as high as 40 and R p as high as 100,000 
while others have ^ only about 2 and R p as 
low as 1,500, but tubes with these extremes are 
used only for special purposes. 

33 GRID POTENTIAL PLATE CURRENT 

FIG. 10 shows a tube with an A battery to 
heat its filament, a B battery to maintain 
its plate current, and a C battery to keep its 
grid negative, and a milliammeter to measure 
the plate current. If the B battery voltage is 



68 



Radio Broadcast 



kept constant while the C battery voltage is 
varied, the plate current will be found to vary 
as shown by the curve of Fig. 1 1 . This curve 
is called the "plate current-grid potential char- 
acteristic" of the tube. By making such a 
curve for each of a number of different B bat- 
tery voltages we obtain a "family" of curves 
as shown in Fig. 12. From inspection of this 
family of curves it is 
easy to find what the 
current would be 
for any combination 
of B and C battery 
voltages. 



35- 



s 



SUPERIMPOSITION OF ALTERNATING CUR- 
RENT UPON DIRECT 

O FAR, all the currents and potentials 



34- THE SQUARE 
LAW "EQUATION 



VMU&lt UNIDIRECTIONAL 
CURRENT OR DIRECT 



AND ALTERNATING CUR- 
RENT BOTH AT ONCE. 



URGE CAPACITY 




LARGE REACTANCE 



HOWEVER we do 
not use this chart 
much, for it is a very 
fortunate circum- 

stance that for all purposes in which we will be in- 
terested, the simple equation Ip = K (B+jxC) ? 
gives the plate current with sufficient accuracy 
especially if there is not much impedance in 
the plate circuit. (Ip is the plate current, B 
the number of volts in the plate battery, C the 
number of volts in the grid battery, and if the 
grid is negative a minus sign must be used, 
and k is a constant whose value depends upon 
the particular tube used, and even with a given 
tube depends upon the amount of filament cur- 
rent). If we had only the experimental fam- 
ily of curves of Fig. 12 as a guide to the beha- 
vior of the tube, we could reason out results 
quite well in a qualitative way, but by using 
the equation we can work out quantitative 
results very much more quickly and simply by 
straightforward elementary mathematics, and 
we will not be so likely to overlook unexpected 
effects. However, for all practical purposes, 
the curves of Fig. 12 will be found quite satis- 
factory. 



ALL THE DIRECT CURRENT 
BUT ONW A SMM1 FRAC- 
TIOH OF ALTERNATING 
CURRENT IN THIS BRANIH 



FIG - '3 



terest is centered on alternating currents, it 
should be explained here that if in addition 
to the C battery an alternating potential be 

applied to the grid, 
ONLY PURE ALTERNATING causing the grid po- 

CURRENT IN THIS BRANCH , . ri 6 

. tential to fluctuate 

about its mean value 
"C", then as a result 
the plate current will 
also fluctuate about its 
mean value. But as 
mentioned before, a 
unidirectional current 
whose strength varies 
about a mean value 
can be considered to 

be two distinct currents flowing simultane- 
ously in the same wire: the first a direct cur- 
rent of constant strength, and the second an 
alternating current whose strength depends 
upon the amount of fluctuation. These two 
currents can be, and often are, fairly completely 
separated out from each other by the device 
shown in Fig. 13. Direct current cannot flow 
through the condenser so it all goes through the 
other branch. On the other hand if the in- 
ductive reactance is very large in the other 
branch compared to the condensive reactance 
of the condenser (at the frequency used) 
most of the alternating current will take the 
easier path, that is, the condenser branch. 
It is not always necessary to effect this separa- 
tion. The whole alternating operation of the 
tube may be summed up by saying that 
against a background of direct currents and 
voltages, the tube receives an alternating volt- 
age input to its grid and delivers an alternating 
current output in its plate circuit. 



Experiments using the two-element tube in reflex circuits are de- 
scribed in the Lab Department next month. The host of reflex 
users will have a whole new field of experiment thus opened to them 



<WHO IS TO 
^BROADCASTINQ *AND JfOW? 

*A Contest Opened by T^ADIO ^BROADCAST 

in which a pri%e of $$OO is ojfered 

What We Want 

A workable plan which shall take into account the problems in present radio 
broadcasting and propose a practical solution. How, for example, are the restrictions 
now imposed by the music copyright law to be adjusted to the peculiar conditions of 
broadcasting? How is the complex radio patent situation to be unsnarled so that 
broadcasting may develop? Should broadcasting stations be allowed to advertise? 

These are some of the questions involved and subjects which must receive careful 
attention in an intelligent answer to the problem which is the title of this contest. 

It Is To Be 'Done 



The plan must not be more than 1500 words long. It must be double-spaced and 
typewritten, and must be prefaced with a concise summary. The plan must be in the 
mails not later than July 20, 1924, and must be addressed, RADIO BROADCAST Who Is 
to Pay Contest, care American Radio Association, 50 Union Square, New York City. 

The contest is open absolutely to every one, except employees of RADIO BROADCAST 
and officials of the American Radio Association. A contestant may submit more 
than one plan. If the winning plan is received from two different sources, the judges 
will award the prize to the contestant whose plan was mailed first. 

Judges 

Will be shortly announced and will be men well-known in radio and public affairs. 
What Information You tN^eed 

There are several sources from which the contestant can secure information, incase 
he does not already know certain of the facts. Among these are the National Associa- 
tion of Broadcasters, 1265 Broadway, New York City; the American Radio Association, 
50 Union Square, New York, the Radio Broadcaster's Society of America, care George 
Schubel, secretary, 154 Nassau Street, New York, the American Society of Composers 
and Authors, the Westinghouse Electric and Manufacturing Company, the Radio Cor- 
poration of America, the General Electric Company, and the various manufacturers, 
and broadcasting stations. 



The independent committee of judges will award the prize of $500 to the plan which 
in their judgment is most workable and practical, and which follows the rules given 
above. No other prizes will be given. 

No questions regarding the contest can be answered by RADIO BROADCAST by mail. 



Jw. 7 JH. l sksfLsCLSfLJCLSPLJCiSfL SdffL A Jfc Jfc JCfc jra Jt& J& fll L Jw. T JO. 



How to Increase Your Range 



Details on How to Apply Radio-Frequency Amplification to Single 
and Two-Circuit Regenerative Receivers, Preventing Radiation 

PART II 
By JOHN B. BRENNAN 



M 



ANY have inquired about details 
suggested by the article by Mr. 
Arthur H. Lynch "How to In- 
crease Your Range," in the 
March RADIO BROADCAST. This 
article will attempt a further explanation in an 
effort to simplify the construction of the radio- 
frequency unit there recommended and de- 
scribed. 

The photographs accompanying that article 
merely illustrated the use of the amplifier unit 
with the coil B coupled to a single circuit re- 
ceiver. 

Coil A is wound as was described, with 80 
turns of No. 25 DCC wire, tapped every 20 
turns. It is not bank wound, as shown in the 
lower right photograph, Fig. 3, page 381, 
March. 

The amplifier unit is shown in Fig. i. 
When applying this unit to a standard 



three-circuit regenerative receiver such as 
Fig. 5, page 440 in RADIO BROADCAST for 
March, the following changes are necessary; 
Disconnect the antenna and ground leads from 
the primary of the regenerative set and connect 
them to their respective posts on the amplifier 
unit as shown in the correct circuit below. Con- 
nect the primary or stationary coil of the coupler 
in the regenerative set to the posts Nos. 8 and 9 
(Nos. i and 2 as in Fig. i, next page). This 
primary coil then becomes coil B (See Fig. i, 
page 380, March). The filament circuit must be 
checked over so as to prevent short-circuiting o f 
the A battery. The set is now ready for use. 
By referring to Figs, i and 2 the method of con 
necting to a single circuit receiver will be quite 
evident. The antenna and ground leads of the 
single circuit receiver are disconnected from the 
binding posts and in their place is connected the 
piece of wire E. This operation shunts the 




6 Volt 

t 0-f- 

' Telephones 

^*--m*P/ifi 



THE CORRECT CIRCUIT 

For changing your single-circuit receiver into a non-blooper by adding a stage of radio-frequency amplification. This is 
the same circuit which appears on page 380 of this magazine for March. There are several corrections: Coil C, lower lead 
goes to the 6 volt lead. If a loop is used in place of an antenna and ground, connect posts i to 2 and plug loop in at 

points i and lA 



How to Increase Your Range 



fixed; in other cases it is made variable by addi- 
tional switch arms. 

Unless the owner of a single circuit set is 
entirely familiar with the wiring circuit of his 
receiver, it is recommended that he secure the 
services of a competent radio mechanic to con- 
struct the amplifier. 

To adapt this circuit to use for radio- 
frequency amplification, the antenna tuning 




FIG. I 

The radio-frequency unit 

variable condenser across the primary coil re- 
sulting practically in the equivalent to Fig. 
i, page 380, March, with the exception that 
instead of a plate variometer, we have a rotat- 
ing coil D coupled to the coil C. The ter- 
minals Nos. i and 2 of Fig. i are connected to 
the 45-turn coil B and this is loosely coupled 
to the coil C. The construction of the coils 
A and B were explained in the March issue; 
however, a brief resume follows : 

About 150 feet of No. 25 DCC wire will be 
plenty for the winding of both coils. The tub- 
ing for the coils A and B is of formica, bakelite 
or cardboard, | inch thick and 3! inches in 
diameter. The tube for A is 3 inches wide and 
for B, 2 inches wide. A margin of about f inch 
is left on either side of the winding of both coils. 

It is to be noticed that the grid leak, which 
usually shunts the grid condenser, is connected 
to the positive side of the filament supply as 
shown in Fig. 2. 

One more word about the single circuit re- 
ceiver. There are many variations and modi- 
fications of the single circuit, but in most cases 
they are of the same principle; that is, the an- 
tenna is connected through a variable condenser 
to a coil, thence through a selector switch arm 
to the ground lead. The grid and filament 
connections are usually taken directly off the 
coil proper. Sometimes this connection is 



so 



FIG. 2 

Connections necessary to change a standard 
single circuit regenerator to a non-radiator 

condenser of the receiving set is shunted across 
the primary coil. This is usually accomplished 
by connecting the antenna and ground binding 
posts with the wire E as shown in Fig. 2. 

An error occurred in the wiring diagram in 
the March issue, page 380. The bottom side 
of the coil C had been left disconnected. It 
should be connected to the negative or ground 
lead. 

In Fig. i, A 80 turns No. 25 D.C.C. wire, 
tapped every 20 turns; B 45 turns No. 25 




To B+ 

FIG. 3 
Circuit of the untuned transformer-coupled amplifier 



72 



Radio Broadcast 




FIG. 4 

The tuned transformer-coupled amplifier. Dotted lines 
show how and where to include neutralizing capacity 

D.C.C. wire tapped every 15 turns; Ci and C2 
.00025 m fd. condensers; 3 .002 mfd. fixed 
condenser; R 3oo-ohm potentiometer. 

MULTI-STAGE RADIO-FREQUENCY AMPLIFIERS 

CONSIDERABLE interest has been shown 
in circuit diagrams showing several steps 
of radio-frequency amplification. It must be 
remembered that for every additional step, the 
control of the set becomes more sharp and 
often critical. This, in a large measure, defeats 
the very purpose for which the added steps were 
ntended. 

There are, however, means for overcoming 
this drawback in the form of neutralization and 




TO e>+ 



FIG. 6 

The circuit for the Superdyne or negative 
feedback for the impedance-coupled amplifier 



negative feedback. Both methods will be dis- 
cussed. 

In general, some of the various forms of radio- 
frequency amplification are: untuned trans- 
former-coupled, tuned transformer-coupled, 
tuned impedance-coupled, and resistance- 
coupled. 



The untuned transformer-coupled type is 
not equally efficient over its entire wavelength 
range as it is for one certain wavelength within 
its band. In other words, it has a peak value 
for most efficient operation. Several steps are 
needed to equal the performance of various 
of the other types. See Fig. 3. 

The tuned transformer-coupled type was, 
and perhaps still is, very difficult to time except 
where proper steps have been taken to include 
the neutrodyne feature in the circuit. This 
renders the set free from the self-oscillation of 




FIG. 5 

Circuit for the tuned impedance-coupled amplifier 

the tubes, allowing easy yet sharp control. 
See Fig. 4. 

The same oscillation trouble was true of the 
tuned impedance-coupled amplifiers, but the 
use of the negative feedback, or Superdyne 
method, partly eliminated this drawback. See 
Figs. 5 and 6. 

In Figs. 3, 4, 5 and 6, only single stages of 
the radio-frequency amplifier units have been 
shown. With the exception of the Superdyne 
method, for more than one stage of amplifi- 
cation the circuit for the successive units 
would be the same, that is, the output of one 
would be connected to the input of the fol- 
lowing unit. 

Several of these various types of radio- 
frequency transformers were dealt with in 
great detail in past issues of RADIO BROADCAST. 
A reference list follows: 

For untuned R. F. transformers, see page 393, 
March, 1923, issue. 

For tuned R. F. transformers see page 393, March, 
1923, issue, page 499, April, 1923, issue, and page 2 14, 
July, 1923, issue. 

For neutrodyne system, see Dec., 1923, Jan., 1924, 
and Feb., 1924 issues. 

For resistance-coupled amplifier, see page 330, 
Feb., 1923; also this issue page 39. 



How to Build the Knock-Out Two- 
Tube Set Behind a Panel 

By WALTER VAN B. ROBERTS 

It is worth knowing that this circuit has given excellent satisfaction as to distance, is not 
hard to build, and is sensitive and does not radiate. Mr. Roberts began work on the circuit 
last December and his original descriptive article appeared in RADIO BROADCAST for April. 
THE EDITOR. 



IN RESPONSE to the demand for a better 
looking arrangement of the circuit de- 
scribed by the writer in the April issue of 
RADIO BROADCAST, the sets shown in the 
photographs have been built, and work 
about as well as the original arrangement. 
For one set the coils were wound on five and 
ten cent store spider web forms, and a five 
and ten cent store brass arm was used to 
operate the tickler coil. The other set makes 
use of coils built especially for this use by the 
Turney Laboratories, 
and can be wired so as 
to appear somewhat 
neater. It has ad- 
justable coupling be- 
tween coils P and S 
of the circuit diagram 
of Fig. i. This fea- 
ture allows maximum 
efficiency over the 
whole wavelength 
range, but it is recom- 
mended that only two 
or three values of this 
coupling be used. Va- 
riation of this coupling 
changes the condenser 
settings. For long 
waves, say 450 to 600, 
have P and S about 
\ inch apart, for the 
range 300 to 450 have 
them, say 30 degrees 
apart, and for very 
short waves, have 
them fully separated. 
They can of course, be 
left at some compro- 
mise position, as in the 



These parts are needed: 
// the set is entirely home built. 
2 General Radio (or equivalent) .005 mfd. con- 
densers. 

.005 mfd. micadon 
.0025 mfd. micadon 

2 25-ohm Cutler-Hammer resistance strips 
Amertran audio-frequency amplifying trans- 
former 

6-ohm rheostat 
UV-20I-A socket 
UV-I99 socket 

Grid condenser with grid leak clips; .00025 mfd. 
condenser, grid leak, 3 megohms 
bus bar (neutralizing capacity "C") 
bus bar for connections 
spaghetti 
binding posts 
panel, formica or bakelite 
wood sub-base 
contact points 
switch lever 

3 coils (3 ten cent store spider web forms, #ire, 
about No. 26 B & S) 

// the set uses purchased coils 

same as above, except parts for the coils are omitted. 

Turney Laboratories coils and mountings. 

Because of the great variation in price of 
these various parts, no price estimate is given. 
Any piece of apparatus which will do the same 
work as a special one mentioned in the article 
may be substituted for it. 



other set, and never varied. Both sets work 
about equally well. 

HOW TO BUILD THE SET WITH HOME MADE COILS 

FOLLOWING are instructions for building 
the set using home made coils: Fig. 4 
shows how to drill the panel. In case it is 
necessary to use other makes of parts than 
those specified, drill only the holes for their 
shafts according to Fig. 4, and then drill holes 
for their supporting screws wherever necessary. 

A baseboard \ inch 
thick with cleats \ 
inch thick is used. 
Fig. 3 shows the po- 
sitions of parts on 
top of the baseboard, 
together with the ap- 
proximate arrange- 
ment of some of the 
wiring. The rest of 
the wiring is easily 
done by referring to 
the circuit diagram of 
Fig. i. Coil A, the 
antenna coil, is mostly 
hidden in the photo- 
graph. Its inner lead 
goes to the antenna 
binding post, which 
is the upper left hand 
one when the panel is 
looked at from the 
front. The ground 
binding post, which 
is just beneath, con- 
nects to the rotating 
contact arm. The 
left contact point 
(viewed from the front 



74 



Radio Broadcast 



V 




FIG. I 

The Roberts circuit. Revised as originally printed last month. Several changes have been 
made. A 3- instead of a 4^-volt C battery is used, a .005 mfd. condenser is added in series 
with winding N, and in the grid return of the UV-igo. is made through the filament 



of the panel) is connected to coil A one turn 
from the inner lead. The next contact point 
connects to the second turn. Point No. 3 goes 
to turn No. 5. Point No. 4 to turn No. 10. 
Point No. 5 to turn No. 20. Point No. 6 to 
turn No. 30. Point No. 7 to turn No. 40, which 
is the outer lead from the coil. Coil A is 
wound of No. 22 d.c.c. wire, winding over two 
teeth, then under two teeth, etc. 

Coils S, one of which hides A in the photo- 
graph, are wound in a similar fashion, and with 
the same kind of wire, but there are 44 turns 



and no taps. The separation between coils A 
and S should be \ to \ inch between centers. 
They are set slightly askew so that they "aim" 
at the centers of the coils at the other end of the 
board. 

Coil T, the tickler, is the coil mounted on the 
rotating arm, and has about 18 turns of any 
kind of magnet wire wound any way. (If os- 
cillations occur before the tickler is turned 
down somewhere near the other coils, there are 
too many turns on it. If oscillations do not 
occur when turned well down toward the other 




FIG. 2 
The home made set behind a panel. As can be seen, the construction is quite simple 



How to Build the Knock-Out Two-Tube Set Behind a Panel 



75 




FIG. 3 

Behind the scenes of the Roberts circuit using the manufactured coils 



coils, the tickler is probably connected back- 
ward.) 

The coil containing the windings N and P is 
the one lying flat on the baseboard. Coil S 
is screwed down on top of it, and separated 
about \ inch by a piece of wood with a hole for 
the screw to go through. N and P are each 
20 turns, being wound both at once by simply 
using a pair of wires instead of a single wire to 
wind with. Wind over one tooth, then under 
one, and so on. Use wires no larger than No. 
26, preferably of different colors so that no mis- 
take will be made in connecting up. 

The sliding contacts on the two Cutler-Ham- 
mer 25 ohm resistance strips should be set so 
that there are about 35 ohms altogether. One 
slider at the end (about 20 ohms) and the other 



at the middle, will be about correct. Never 
remove the 201 -A tube from its socket while 
the filament of the UV-I99 is lighted, as this will 
increase the current through the 199. Connect 
the outer lead of the coil S which is coupled to 
coil A, to the grid of the 201 -A tube, but the 
inner lead of the other S coil to the grid of the 
199. The stationary plates of the condensers 
are the ones that are connected to the grids in 
both cases as is indicated by the diagram. If 
the rotating arm on which the tickler is 
mounted happens to be bent the wrong way, 
saw it off and solder together the other way 
around. Be sure that the terminal marked P 
on the primary of the Amertran is connected 
to the tickler, not to the B battery terminal. 
If some other make of transformer is used, try 




-Iff- 



,**> 



-y/i 



FIG. 4 

Panel layout for the home built set. The panel with manufactuied coils is three inches longer 



7 6 



Radio Broadcast 




FIG. 5 

Front view of set using manufactured coils. The 
has plenty of leeway in building his own set 

connecting its primary both ways to see which 
works right. In connecting windings N and P, 
first connect the outside lead of one to the in- 
side lead of the other. Be sure not to simply 
connect the outside lead of one to its own inner 
lead. 

The neutralizing capacity, C, is easily made 
by leaving two inches of bus bar projecting 
from the grid terminal of the 201 -A tube. This 
is covered with spaghetti. A brass tube con- 
nected to the free end of winding N is then 
slipped over the spaghetti, fitting snugly. 
(Bare wire wrapped tightly around the spa- 
ghetti will do instead of the tube.) 

See the article in the April RADIO BROADCAST 
for directions for adjusting the capacity C, and 
for the theory of the operation of the set. 

THE SET WITH PURCHASED COILS 

THE set using the Turney coils was built on 
a 2 1 -inch panel to make it less crowded. 
The baseboard, however, is only 16 inches 



experimenter 
of this type 



long. Coils A and S are 
mounted 2 inches from 
the panel and parallel to 
it. The circuit is the 
same as in the other case, 
although the wiring is 
slightly altered to suit the 
different arrangement of 
parts. 

In both sets, General 
Radio .0005 mfd. con- 
densers with slow motion 
gearing are used. The 
rheostat is 6 ohms. The 201 -A socket is 
a Paragon, while for the 199 tube, either Para- 
gon, General Radio, or Radio Corporation 
sockets are recommended. Binding posts, 
contact points and panel, can be got at the five 
and ten cent store. 

To get an idea of what performance to expect, 
the following is of interest: WGY is received 
quite satisfactorily on the loud speaker in 
Princeton, N. J. at any time of day, and KDKA 
can be heard faintly. At night KHJ is barely 
audible on the loud speaker, while KGO is 
almost loud, and can be separated perfectly 
from WLW, whose wavelength is only i per 
cent, different. (The respective settings of 
these two stations on the set using the home 
made coils are 23 and 22|.) 

The original set described in the April RADIO 
BROADCAST is now being used by Dr. L. A. 
Turner of the Dept. of Physics, Princeton 
University, who has heard KGO on the loud 
speaker, using an indoor antenna! 




What Our Readers 
Write Us 




Wiib the Broadcast Listener in Samoa 

A^ONG with this extraordinarily interest- 
ing letter from Mr. Roberts came several 
copies of a twenty-page radio bulletin which 
the enthusiastic listeners of Samoa issue "every 
once in a while" under the direction of Mr. 
Roberts who types the thing. We regret we 
haven't space for it. However, the transatlantic 
tests which RADIO BROADCAST sponsored last 



November were by no means unsuccessful, as 
the flood of letters we received demonstrated 
conclusively. 

Consulate at Apia, Samoa, January 21, 1924 
Editor, RADIO BROADCAST, 
Doubleday, Page and Co., 

Garden City, L. I. 
DEAR SIR: 

I have read in the January issue of RADIO BROADCAST 
an account of the transatlantic broadcasting tests. It ap- 



What Our Readers Write Us 



77 



pears that interest in the test was general, leading broad- 
casters, eminent engineers on both sides of the Atlantic, 
the press services, and prominent men cooperating in the 
tests. 

Using super-heterodyne receivers at Garden City, faint 
voice and music was heard. The Radio Editor of the 
New York Times writing December 9, 1923, indicates that 
the tests from the view point of the American listeners were 
failures. Broadcasting stations, spark stations, and static 
interfered with the tests. 

I have briefly summarized the results of the transatlantic 
tests as gathered from my latest magazines and papers in 
order to compare your results with the success of the trans- 
pacific tests now being carried on by WBAP the Star- 
Telegram, Fort Worth, Texas. 

Incidentally, it may be of interest to learn that RADIO 
BROADCAST is responsible for the transpacific tests. Mr. 
G. C. Arnoux, Program Director of WBAP, read "When 
the Bug Bit in Samoa" in the October number of RADIO 
BROADCAST and wrote me suggesting a series of tests with 
Samoa. 

The proposal was brought to the attention of the broad- 
cast fans of Western Samoa who established a listening-in 
schedule drawn up to eliminate interference from Apia and 
Tutuila spark stations and from the single-circuit regenera- 
tive receivers in operation in the vicinity of Apia. Radio 
fans were to listen in on the following dates: 
NPU Tutuila Radio Station, American Samoa. All dates. 
VMG Apia Radio Station, Apia, Samoa. All dates. 
Father J. B. Dumas, Aleipata, Upolu, Samoa. All dates. 
W. R. Ragsdale, Palauli, Savaii, Samoa. All dates. 
Quincy F. Roberts, Apia, Samoa. January 6, 1924. 

1 1.30 p. M. to 12:30. 
John H. Dixon, Apia, Samoa. January n, 1924. 11.30 

p. M. to 12.30. 
VMG was given January 9, 1924. free from interference 

from the single circuit regenerative receivers. 
All stations January 21, 1924, and January 23, 1924. 
1 1.30 P. M. to 12.30. 

The difference in time made WBAP's transmitting hours 
from 5.00 A. M. to 6.00 A. M. January yth, loth, i2th, 
22nd, and 24th. 

On January 6, 1924, the music from the Coconut Grove 
Orchestra at the Ambassador Hotel, Los Angeles, trans- 
mitted through KFI ended. The next three hours were 
spent in cleaning connections, adjusting voltages, and 
changing tubes in an effort to find the right combina- 
tion for best results. At 11.30 WBAP'S carrier wave 
came in. Adjustments brought in voice. Bang. Apia 
Radio opened up with its 8 kilowatt spark set. Tutuila 
came back with his br'oad spark. Several ship sparks 
joined the chorus. Both NPU and VMG had forgotten 
the Fort Worth tests. The telephone service was over 
hours earlier. There was no way of informing VMG 
that his spark was drowning out WBAP'S messages. We 
could hear voices and strains of music between the dots 
and dashes. 

Static and interference had combined to make the first 
test a failure, but the strength of the signals was sufficient 
to convince the radio fans of Western Samoa that under 
more favorable conditions WBAP would span the Pacific. 

Receiving conditions during the second test were slightly 
better. Static was heavy. Lightning flashed on three 
sides of Apia. Two or three ship stations were using a 
frequency which overlapped the Fort Worth wavelength. 

WBAP, in the heart of Texas, came on the air at 5.00 
o'clock in the early winter morning of January is, 1924. 



Radio enthusiasts of Samoa in the last half hour of mid- 
summer January 9, 1924 caught the signals. 

Clear and strong the Texan spanned the Pacific with, 
"This is WBAP, the Forth Worth Star-Telegram of Fort 
Worth, Texas, United States of America calling 
NPU American Samoa, 
Savaii Radio Station Savaii, Samoa, 
Apia Radio Station Apia, Samoa, 
Mr. Quincy F. Roberts, American Vice Consul in charge, 

Apia, Samoa, 

Father J. B. Dumas, Aleipata, Samoa, 
Mr. John H. Dixon, Apia, Samoa, 
Mr. W. R. Ragsdale, Palauli, Samoa, 
All stations in New Zealand, Australia, Java, Borneo, 
Sumatra, Japan, Philippines, and China. 
If you receive this send a cablegram or a radiogram to the 
Radio Department of the Fort Worth Star-Telegram, Fort 
Worth, Texas, and we will refund telegraphic charges to 
you. This is station WBAP, Fort Worth Star-Telegram, 
Fort Worth, Texas, United States of America. Stand by. 
We will change to Morse then give you music." 

Morse followed. Then the operator shifted to the pipe 
organ and a longing for home filling the hearts of the lis- 
teners brought tears to their eyes as old familiar melodies 
came through space. 

My wife looked up and said. "We've been away too long. 
We must go home in April." 

Then and there we decided to return to the United States 
in the Spring. Fort Worth's second test is bringing joy to 
a family in the hills of Tennessee and to another on the 
Great Lakes. Our relatives are receiving word that we are 
due in New York next May. 

Imagination did not help in the long distance reception. 
Although static was exceptionally heavy and spark sta- 
tions interfered, I can safely say that the entire program 
was received. It was possible for us to recognize the 
accent of the announcer. We marked errors in the pro- 
nunciation of Samoan village names as the speaker strug- 
gled through the list of places he called. 

Mr. W. R. Ragsdale from Savaii writes, "Speech and 
music transmitted by Fort Worth came in at my station. 
The signals were very loud on a single dry cell tube. Con- 
versations were recorded and will be submitted for verifica- 
tion upon the conclusion of the tests. Static and spark 
stations interfered badly, but it was almost impossible to 
miss WBAP and his cow bells." 

Mr. John H. Dixon, Plant Engineer at Apia Radio re- 
ports, "Static was bad during my test with WBAP. I 
heard the announcer request South Pacific, New Zealand, 
and Australian, stations to report on the test. Organ 
music came in. As the names of the pieces played were 
not announced I can not give the complete program." 

There are only two more stations to report. VMG did 
not listen in. NPU'S short wave receiver failed and was 
in Honolulu for repairs during the tests. Father J. B. 
Dumas and Doctor R. L. Christie have not yet had an op- 
portunity to send in their reports to Apia from Aleipata. 

The results so far are three of the five broadcast fans 
of Western Samoa using a single tube variometer set, a 
single-circuit regenerative receiver with two stages of 
audio-frequency amplification, and a five-tube receiver with 
two stages of radio frequency and two stages of audio- 
frequency amplification succeeded in receiving WBAP 
through static and spark signals, a distance of 5,850 statute 
miles. 

The reception of American broadcasting stations by the 
fans in Western Samoa is no longer considered remarkable. 



Radio Broadcast 



Seldom are receiving conditions so unfavorable that music 
transmitted by the high powered Pacific Coast stations can 
not be tuned-in. 

The following American stations are heard regularly in 
Samoa : 

KFI Los Angeles 4.75 miles 

KHJ Los Angeles 4.750 miles 

KPO San Francisco .... 4,750 miles 

KGO Oakland 4.75O miles 

WJAZ Chicago 6,555 miles 

Wednesday working WNP 

WDAF Kansas City 6,no miles 

Night Hawk Frolic 

Other stations heard at various times are: 

KLX Oakland 4,75 miles 

KGW Portland 5,080 miles 

WBAP Fort Worth 5,850 miles 

Test only. 

CFAC Calgary 5,620 miles 

Test only 

An examination of the two lists clearly shows that inter- 
national broadcasting between the United States and 
Samoa is carried on during the winter months of the tem- 
perate zone. Our small receivers consistently night after 
night reach out 5,000 miles and bring in American pro- 
grams. It may be there is a scientific explanation for the 
long distance records made in Samoa. A study of the 
territory covered by the larger stations plotting the most 
distant points reached might be interesting. I know that 
maps showing the territory covered by KFI, KGO, KPO, 



WHB, and WJAZ would be interesting to the amateurs of 
Samoa. Very respectfully yours, 

QUINCY F. ROBERTS, 
American Vice Consul in Charge. 

Win at to Do About Radiating Receivers 

Editor, RADIO BROADCAST, 

Doubleday, Page and Co., 

Garden City, L. I. 
DEAR SIR: 

In your March issue, Mr. Dreher in his article "Is the 
Broadcast Listener at Fault" strikes the right chord when 
he states that the remedy for many of the listener's 
troubles lies in education of the public. First, the adver- 
tiser should be educated to state whether or not the re- 
ceiver he is selling radiates; second, all radio magazines 
should be educated to state in connection with every "hook 
up" printed whether or not it is a radiating circuit, and 
third, all radio magazines should be educated to run con- 
tinually instructions as to how to operate radiating re- 
ceivers without raising the dickens for a dozen or so blocks 
around them. A new crop of suckers is born every spring 
and it takes the repeated instruction to keep up with the 
new crop. There might be added a fourth point, that the 
magazines should be educated to cease asking for reports on 
DX reception. Calling for such reports only serves to 
stimulate the "squealers" to greater activity. 

You have started a good educational campaign, but I 
take it you have "some job" ahead of you yet. 

Yours truly, 
P. R. VAN FRANK, 
Memphis, Tenn. 



The Grid 

QUESTIONS AND ANSWERS 



The Grid is a Question and Answer Department maintained especially for the radio amateurs. Full 
answers will be given wherever possible. In answering questions, those of a like nature will be grouped 
together and answered by one article. Every effort will be made to keep the answers simple and direct, 
yet fully self-explanatory. Questions should be addressed to Editor, " The Grid," RADIO BROADCAST, 
Garden City, N. Y. 



NON-RADIATING RECEIVERS 

/ read with great interest the article in the March number of 
Radio Broadcast on " The Truth About Trick Circuits." 
Allow me to congratulate you on the courageous stand you 
have taken. 

I have been considering for some time, the purchase of 
a Tuska Superdyne receiver, but am now hesitating for fear 
it may be one of those referred to in the article. Will you 
please tell me if it is a re-radiating receiver? 

O. A. J., ROCKVILLE CENTER, N. Y. 

FI RST allow us to correct our correspondent on 
the prevalent mis-use of the term "re-radiating." 
Re-radiating means, of course, radiating again 
which in very few cases is the phenomenon referred to 
when the term is applied to oscillating receivers. Re- 



radiation occurs when resonant or tuned objects, such as 
wire fences, guy wires, the steel frames of buildings, etc., 
pick up energy from a near-by and powerful transmitter 
and, by impulse excitation, retransmit a portion of this 
energy on their individual wavelengths. 

In the case of a banned receiver, the set itself is a small 
transmitting station, generating its own power which is 
sent out on the air to make itself evident as squeals and 
whistles in neighboring receivers. Thus the oscillating 
receiver is correctly termed a radiating set, the prefix re 
being unnecessary and meaningless. 

The Tuska Superdyne receiver, when correctly operated, 
is not a radiating set, and many of our readers have found 
it a most satisfactory equipment. Oscillation in the first 
tube which results in radiation, is prevented by what is 
known as reversed feedback. Most of us who have used 
tickler feedback receivers have learned that the receiver 



The Grid 



79 



will generate and oscillate only when the tickler coil is 
"connected in the right direction." If the leads to this 
coil are reversed, the effect is quite the opposite of regenera- 
tion the circuit refuses to oscillate, and signals are 
weakened as the tickler is more closely coupled to the grid 
circuit. This is the reversed feedback principle employed 
in the Tuska Superdyne, which permits the set to take 
full advantage of tuned plate (resonant) radio-frequency 
amplification. 

For the benefit of our interested readers, and to save 
them the trouble of communicating with us, we herewith 
list a few of the more prominent non-radiating receivers. 

All forms of radio-frequency amplified sets are non- 
radiating when properly operated. It is impossible to 
secure satisfactory reception when they are oscillating. 
This broad statement completely covers the following: 

The Neutrodyne, which is probably the most stable of 
all R. F. receivers. 

The reflex sets De Forest, Grimes, single tube, Erla, 
Acmedyne, etc. 

Receivers having aperiodic primaries, while they radiate 
to a slight degree, are far less bothersome than other types 
of regenerative receivers, and, in most cases, they may be 
used with a clear conscience. This circuit is shown in 
Fig. i. The Haynes circuit, which was inadvertently 
and incorrectly mentioned as a "trick circuit" in the 
article to which our correspondent refers, is representative 
of commercial instruments of this type. 

The super-heterodyne when used with a loop may be 
considered as a non-radiating receiver, even though the 
principle upon which it functions depends on a constantly 
oscillating circuit. These oscillations, however, are con- 
fined to two small coils within the receiver, and for this 



reason they are not radiated to any git-ax. extent. Even 
this very small radiation has been practically eliminated 
on broadcasting wavelengths in Armstrong's latest varia- 
tion of his original receiver which is called "The Second 
Harmonic Super-heterodyne." This receiver, rather than 
using direct oscillations in the neighborhood of the re- 
ceived frequency, employs a widely different main fre- 
quency, the comparatively weak second harmonic of which 
replaces the usual heterodyning wave. This system makes 
practicable the super-heterodyne on the extremely short 
waves below one hundred and fifty meters, where, using 
the main oscillating wave, the radiations, which are 



characterized by a remarkable efficiency, would carry 
fully as far as the lower frequencies now do on the antenna 
operated "bloopers." 

THE THEORETICAL "WHY" OF R. F. AMPLIFICATION 

In these advanced days, when radio-frequency amplification 
is the keynote of wireless reception, I think many of your 
readers, including myself, would appreciate it if you would 
clear up a theoretical point that has bothered me for some time. 

I do not understand how radio-frequency oscillations are 
passed on from one tube to the next tube. I have always 
been taught that the plate cut rent, which of course is responsible 
for the inter-tube transference of energy, is a direct current. 
Thus it seems to me that a single tube is all that is required to 
block effectively a high frequency alternating current such as 
forms a radio signal. And yet it appears that three or four of 
such tubes do not block or impede the progress of these currents 
in any way, but to the contrary intensify them Why? 

B. J. S., NILES, Mich. 

THE phenomenon which puzzles our reader is, briefly, 
how can a vacuum tube, through which only a di- 
rect current may flow, pass an alternating current 
on to the next tube? This is explained by pointing out 
that the tube does not pass on the original current which 
was applied to its input side rather each tube "gen- 
erates" on its output side an entirely new alternating cur- 
rent, which, however, is an amplified duplicate of the ori- 
ginal impressed signal. 

The majority of our readers are familiar with the action 
of the three element vacuum tube, the plate current of 
which is an electron stream, thrown off by the filament, 
attracted to the plate by the positive B battery charge, 
'hich may be varied by an additional charge placed 
upon the intervening grid. The slightest variation of the 
original grid potential either impedes (with a minus var- 
iation) or increases (with a plus variation) the plate (or 
space) current. Thus, when an alternating current, or a 
radio impulse is impressed on the grid of the tube, which 
means that the original grid charge is momentarily aug- 
mented and lessened, the direct plate current becomes 
stronger and weaker. 

The plate current, after the manner of all currents, sets 
up in its immediate vicinity a magnetic field, which, if 
the plate current is made to flow through the primary of a 
radio-frequency amplifying transformer, will "cut" the 
secondary. The magnetic field varies with the strength 
of the current which sets it up, and thus the flux will rise 
and fall, keeping perfect time with the grid variations. 
When a magnetic field moves in this manner, an alternating 
current is set up in any adjacent windings such as the 
secondary of the amplifying transformer. 

This alternating current is now impressed on the input 
side of the succeeding tube where the process is repeated. 
Thus each radio-frequency amplifying tube relays an alter- 
nating current on to the next audion, without actually 
passing any of the input current. 

PHANTOM CIRCUITS AND PHANTOM RECEIVERS 

/ read with great interest the article in the March RADIO 
BROADCAST showing how the old standard circuits are dressed 
up in deceptive garments by unscrupulous and ignorant 
dealers. 

I have been interested in the possibilities of the Oard Phan- 
tom Receiver, manufactured by the Oard Laboratories, Stock- 



8o 



Radio Broadcast 



ton, California. I should appreciate your informing me if 
this receiver employs the "phantom" circuit described in the 
article in question. R. O. M., Milwaukee, Wis. 

NO. THE circuit employed in the Oard Phantom 
Receptor is a different one. Moreover, the 
manufacturers of this receiver do not claim their 
circuit to be a new one, but distinctly mention in their 
advertising matter that it is licensed under the Armstrong 
regenerative patents. 

This undesirable association of the Oard Receptor with 
the "phantom circuit" described in the March RADIO 
BROADCAST is additionally illustrative of the "gyp" phase 
of our young industry. Following the national advertising 
campaign of the Oard people, an unscrupulous concern 
advertised "the famous Phantom circuit" which, through 
natural association, cashed in on the Oard advertising. 

This commercial plagiarism is found in all varieties of 
endeavor, but it is particularly malignant in budding in- 
industries, such as radio now is. The "Micadyne" con- 
denser is another example of "gyp" enterprise. The 
"Micadyne" is an obvious and unjust take off on the 
Dubilier "Micadon," and a permanent injunction has been 
issued enjoining the counterfeiters from manufacturing the 
"Micadyne." 

The radio enthusiast will find many other misleading 
trade similarities. He should discover, if he can, the 
original product or prototype, and beware of the imitation. 
An honest product will stand on its own legs and an honest 
manufacturer does not stoop to camouflage or deception. 

"Accept nothing but the genuine", has been applied to 
everything from pills to suspenders, but in no industry 
should this warning be taken more seriously than in radio. 

WHEN Is MY SET OSCILLATING? 

/ have a three-circuit regenerative receiver which I under-\ 
stand should not interfere with my neighbors as much as would\ 
a single-circuit set. However, another fan, living next door \ 
to me, claims that he hears me when my set is oscillating. I j 
have no desire to interfere with his pleasure, and am always ' 
unaware of the fact when my set is radiating. Is there any 
way that you can tell definitely when a set is oscillating? 
A. T. R., Roswell, N. M. 

IT IS often difficult for the untrained radio ear to de- 
termine when a circuit is oscillating. However, you 
may be certain that you are causing trouble when, as 
you tune across the wave of the broadcasting station, a 
whistle is audible that varies directly with your tuning. 
A sure test for oscillations is touching either the grid 
connection of the tube, or the antenna binding-post. A 



slight click or scratch will always be audible when this 
is done, but a much more definite "blop" will be heard 
if the circuit is oscillating. However, touching the antenna 
post only affects the first tube, and the grid connection 
should be touched when testing radio-frequency amplifiers, 
difficulty with which is often caused by one or more of the 
tube circuits falling into oscillation. 

Oscillations are controlled in most receivers by turning 
down the filament and by reducing regeneration. In 
radio-frequency stages, they are generally eliminated by 
potentiometer adjustment, reduction of filament current, 
and by reducing the plate voltage. 

A. C. AND D. C. CHARGERS 

Is there any difference in storage battery chargers operating 
from the house lighting lines, as determined by whether the 
user is supplied with alternating or direct current? 

A. L. J., New York City. 

YES, there is all the difference in the world. A charger 
designed for alternating or direct current will 
operate only on the current supply for which it was 
intended. A direct current charger, connected to an 
alternating current source, will not charge, while an A. C. 
charger connected to direct current mains will burn out its 
primary winding, or blow fuses. 

Direct current for charging need only be reduced to the 
proper voltage, while alternating current must be reduced 
and then rectified to direct current. Direct current volt- 
ages are generally reduced by the inclusion in the circuit 
of a suitable resistance. The Ward-Leonard direct current 
charger is an excellent example of this type of apparatus. 
Alternating current chargers consist of step down trans-_ 



I 



ABOUT YOUR GRIL, . 

Judging from the rapidly increasing demands made upon this section, it is per- 
forming a valuable service but it is getting to be a very serious problem. 

As a general rule replies to letters addressed to the GRID require the drawing 
of a diagram or two and a considerable amount of research. Similar service, if 
purchased elsewhere, would cost a very tidy sum. We are pleased to offer this serv- 
ice to our readers without charge but feel that it is up to our readers to cooperate 
with us to the extent of sending, with their requests for information, a self-addressed, 
stamped envelope. Unless our request is complied with the GRID will be unable 
to consider these inquiries. THE EDITOR. 



RADIO BROADCAST ADVERTISER 



Improve your set with an 

ACME "lowest loss" condenser 



Because of low losses and sharp 
tuning practically all the currents on 
the antenna can now be used 





Which one is your 

tuning circuit 

the hump or peak? 

HERE are the curves of two tuning 
circuits The hump has a high loss 
condenser and the peak a low loss con- 
denser Both receive broadcasting, but 
the peak receives local and distant stations 
without interference, while the hump re- 
ceives only the nearby stations with inter- 
ference The new Acme Condenser will 
change your tuning circuit from a hump 
to a peak 

The Acme Engineers have been working 
for two years to bring out a condenser 
which would give to Radio experimenters 
sharp tuning and minimum losses. The 
new Acme Condenser has these fundamen- 
tal advantages and also has many new 
improvements in structure and equipment. 
See the illustration with explanation, and 
for more information write to us for bock 
let "Amplification without Distortion," 
which contains many diagrams and help- 
ful hints on how to build and get the 
most out of a set. 

ACME APPARATUS COMPANY 

Dept 65 Cambridge, Mass 



11 

12 

13 
14 
35 



678 




12 



14 



13 



1. Steel brass cone bearings adjustable. 

2. Lock nut for bearing. 

3. Highest grade hard rubber Dielectric in that part of 
the field to prevent losses 

4. Brass separator to which both rotary and stationary 
plates are soldered, making continuous circuit for each. 

5. Brass silver plated plates, rotary plates logalogarithmic. 

6. Dust proof covering 

7. Stops at extreme end of movements 

8. Coiled connection between shaft and heads allowing 
lubrication of bearings. 

9. Brass separator to which both rotary and stationary 
plates are soldered, making continuous circuit for each. 

10. Counterweight which balances rotary plates 

Noiseless friction Vernier control seven to one ratio. 



Brass separators to prevent twisting and to take strain 

off Dielectric 

Panel, mounting holds for 120 degrees spacing. 

Metal heads 

Steel bushing to prevent wear on Vernier shaft. 

All parts are of non-rusting metal, except steel bearing, 
which is covered with nickel-plated protective surface. 
End plate capacity is .000016 m f full capacity is .0005 
m.f. Price $6 50 

CUT OUT AND SEND THIS COUPON 



ACME APPARATUS COMPANY, 

Dept 65 Cambridge, Mass USA 

Gfntlemen; I am enclosing 10 cents (U S. stamps or 
coin) for a copy of your book, 'Amplification without 
Distorticn " 

Name 

Street 

C-ty. 



State 



ACME ~f r amplification 



Tested and approved by RADIO BROADCAST 



I 




Harris & Kwing 

WALLACE H. WHITE, JR. 

The author of the bill which proposes further to regulate radio communication in the United States. Among other 

things the bill contains stringent provision against monopoly in radio and provides for license fees to be collected by the 

Department of Commerce, ranging from $300 for transatlantic stations to fifty cents for an amateur license. Owners of 

receiving sets are not subject to a charge. Mr. White represents the second Congressional District of Maine 



RADIO 




Vol. 5, No. 2 




June, 1924 



Can We Save Millions by Altering 
the Telegraphic Code? 

From a Close Study of the Plan Proposed by Major-General George O. 
Squier It Would Seem Possible. This plan deserves Serious Consideration 



By ARTHUR H. LYNCH 



S3MEONE has been sleeping. In fact 
so many of us have been sleeping that 
we've simply let a problem involving 
a saving of millions slip right by for 
more than seventy years* without 
troubling for a solution. Perhaps our noses 
have been so close to the picture as to distort 
our* perspective. Major-General George O. 
Squier who told this story to me at the Metro- 
politan Club in Washington, D. C., a few weeks 
ago said : " The neglect on the part of the radio 
telegraph industry to alter its only product is 
a problem in psychology of sufficient magni- 
tude to warrant the study of a James." 

"Our automobile factories, for instance," 
continued the General, " are never satisfied with 
the product they turn out. Even though they 
spend veritable fortunes for machinery to make 
a certain type of car, whether it be a truck 
or a luxurious sedan, they go right on develop- 
ing new models. And they find it profitable. 
" More efficient cars, more efficient produc- 
tion methods, more rapid turnover and a 
greater volume of business usually result in a 
lower price and better service to the consumer 
and the demand continues to grow each year. 

The present radio alphabet was adopted by the Vienna 
Convention for European languages in Oct. 1851. 



"Can you imagine any automobile corpo- 
ration attempting to sell wheelbarrows pro- 
duced in factories capable of turning out the 
best-grade pleasure car in the world?" The 
General's eyes sparkled and the color rose in his 
cheeks as he continued: " That's exactly what 
we're trying to do in radio telegraphy and 
they're flat-wheeled barrows at that. 

"WE ARE ASLEEP IN RADIO" 

"\ A 7HY, just imagine how ridiculous it 
V V would be for a factory representative of 
any large company attempting to secure orders 
for his product from samples made in 1851 or 
thereabouts! It's preposterous. 

"Now, let me briefly outline for you what I 
maintain is one of the greatest pieces of neglect 
in the entire communications art. Then, 
having told you of our short-sightedness, let me 
tell you what I think about solving the problem. 
Understand me, I do not maintain that my 
method of solving the problem is the best 
method, nor that it is impossible to improve 
upon it. All I want to do is to demonstrate the 
need for a revision of our radio, telegraph and 
cable traffic which will cause a great financial 
saving annually. Then I want to tell you how 
I believe it can be done. If my system can be 



Radio Broadcast 



improved upon, so much the better. All I 
claim for it is that it is a step in the right di- 
rection. 

" Radio's function, or to be more exact, one 
of its present functions, is to transmit intelli- 
gence from point to point. In the case of 
ships at sea and aircraft it is the only 
method. When we send a telegram or a 
cablegram or a radiogram, we pay to have 
a small piece of paper, bearing a few char- 
acters, delivered to a person or persons some 
distance from us. The more messages we 
wish sent, the greater the number of little 
papers the company delivering them must be 
able to take care of satisfactorily. In many 
instances the lines between us and the person 
on the other end are heavily laden with mes- 
sages sent by other folks and our messages 
suffer a delay. 

" Something must be done to offset the delay. 
It is sometimes necessary, because of the great 
volume of traffic to have a great many similar 
lines between two points to carry the heavy 
burden of traffic. Engineers, ever since electric 
signaling was discovered have studied the 
action of the machines used in transmitting 
and receiving this intelligence. They have 
made astounding improvements and have in- 
creased the speed of transmission many, many 
times. Why it was but last night that both 
you and I witnessed a transmission of a dot 
sent from the lecture room of the Cosmos Club 
to Warsaw and back again to Washington be- 
fore we could say Jack Robinson. 

"If we had suggested any such thing a few 
years ago people would have shaken their heads 
and have had grave doubts of our mental 
stability. But it was done before our very eyes. 

"Although my plan is not at all confined to 
radio but may be employed on the cables and 
telegraph and even the telephone lines, we will 
do well, for the purpose of explanation to stick 
to radio and the necessary changes for all forms 
of wire application will suggest themselves to 
most of your readers. 

" You know as well as I do that radio trans- 
mission, especially over long distances, such as 
between America and Europe is subject to cer- 
tain atmospheric disturbances during the sum- 
mer. Although engineers have made great 
strides in overcoming this interference there 
are many periods when it is necessary for the 
transoceanic traffic to be handled at very low 
speed and when it is necessary to have each 
word repeated two or three times. 



That means a severe crowding of the ether 
lane used by any two stations being used for 
intercommunication and the few available 
wavelengths preclude the possibility of doub- 
ling up the number of stations to offset this 
difficulty. 

" If we consider that for a definite period of 
unfavorable atmospheric conditions it were 
possible for us to double the speed of trans- 
mission during the favorable hours of each day. 
we would double the revenue of our system for 
that period. Further than that you know 
that most of the messages sent from this 
country to Europe are important. Many of 
them have to do with ships, shipping, foreign 
exchange and so on. With each day, the 
importance of our communication with Europe 
becomes even greater. Offsetting by even a few 
moments in the delivery of a message sent by 
one of the large banks, like the Irving National 
or National City Bank to a bank in Germany 
or England may result in preventing a loss of 
thousands of dollars to American investors. 
Commerce to-day is on what manufacturers 
are pleased to term a production basis. Speed 
in communication is everything. 

"Manufacturers in most lines spend thou- 
sands yearly, attempting to lower costs of 
production by saving a little time here and a 
little material there. Efficiency seems to be 
our war cry and it is just here that radio suffers 
by comparison with other industries. 

PRODUCING CAVE-MAN VEHICLES IN LIMOUSINE 
FACTORIES 

WE'RE selling a seventy-year old model 
and turning it out in modern factories. 
We have million dollar factories on occasion 
covering many square miles for the sole pur- 
pose of sending dots and dashes. We have been 
in short, perfectly content to take things as 
we find them and make the best of it." 

Then the General took a long pull on his 
cigar, looked at the ceiling and exhaled the 
smoke slowly and thoughtfully. He smiled, 
sensing my unspoken question. 

"Oh, no!" he said, "I am not discounting 
any of the wonderful work the engineers have 
accomplished, either in the design of trans- 
mitters or receivers. I am merely saying that 
they have overlooked the little pieces of paper 
that carry the thoughts of one individual to 
another. 

"Their transmitters and receivers are won- 
derful. But the product of the factories must 




MAJOR-GENERAL GEORGE O. SQUIER (RETIRED) 

Who, since his retirement on January ist as Chief Signal Officer of the army after more than forty years of continuous 
service, has been indulging in long deferred plans to carry out experimental work in electrical communication engineering 



Radio Broadcast 



TABLE I 
RESULTS OF INTERCHANGING THE SIGNALS FOR THE LETTERS "O" AND "M" 



For International Morse: 

Present values of these letters: 

O frequency in 10,000, times length of signal . 844 x 14= 11816 
M . 273 x 10 = 2710 

Total 14546 
Values if interchanged: 

O frequency in 10,000, times length of signal . 844 x 10 = 8440 

M . 273 x 14 = 3822 

Total 12262 

(..tin ;iv :i n-Milt of interchange = 14546 12262 = 2284 units 



For Squier Alphabet: 

Present value of these letters: 
O frequency in 10.000, times lenpth of signal 
M " " ' " 



Values if interchanged: 

O frequency in 10,000, times length of signal 
' 



844 x 4 = 
273 x 3 = 

Tots 

844 x 3 = 

273 N 4 = 



3376 
819 

4 I OS 

2532 
1092 



The now total for all letters would therefore he . 

minus 



92334 
2284 



90230 units 

1 he ratio of the new value to the old value is 902 so : 92334 = i : 1.02 5 
The increase in speed expressed in percentage is 2.;' , 



Total 
Gain as a result of interchange = 4195 3624=571 units 

The new total for all letters would therefore be. . ^7 

Minus ; 



The ratioof the new value to the old value is 35170 : 35741 = i 
The increase in speed expressed in percentage is 1.6% 



units 
: 1.016 



The system described here by General Squier does not disclose the additional advantage to be gained by changing the 
code characters foi each letter of the alphabet. Some idea of the importance of such a revision may be seen from a con- 
sideration of "O" and "M". Other letters may be similarly transposed, as the system provides, with an additional saving 



be the International Continental code and the 
code well, I often wonder why its revision has 
not been taken in hand long ago." 

Here indeed was an interesting side light on 
this great industry of ours. I wondered too. 
The thought is not an entirely new one. I had 
thought of it several times during some of the 
long hours of a night watch, when at sea as an 
operator. It had occurred to me when the 
change was made from the American Morse 
Code to the Continental Code, shortly after 
American ships began carrying radio as a 
regular thing. I '11 wager the same thought has 
occurred to thousands of radio men at one time 
or another. The psychological analysis of this 
condition is, as the General puts it "worthy of 
a James." 

"That," continued the General, is my argu- 
ment, in a nutshell. In this little pamphlet, 
a reprint of a short paper I delivered on 
this subject before the National Academy of 
Sciences last May, you will find the outline of 
one system which I am sure may be used to great 
advantage in any form of electrical signalling." 

The following paragraphs, taken directly 
from the pamphlet, outline just what revisions 
of our code General Squier advocates and 
indicate some of the advantages he claims for 
such a system. 

CONSIDER THE CODE 

IN TH E Morse alphabet we find the principle 
of different time units for dots, dashes and 
spaces, as the basic idea of the system. In 
Standard Morse a dash is three times the 



length of time of a dot, and the spaces between 
letters and words are timed correspondingly. 

"These signals in International Morse (Con- 
tinental), are universally emitted into the ether 
from the transmitting antenna in the form of 
sudden interruptions in the antenna current, or 
sudden variations in this current. This method 
produces about the worst possible source of dis- 
turbances in the ether space for the reason, 
among others, that the disturbance has no 
regularity of any kind, and the speed of operat- 
ing the sending key has a marked influence on 
the whole phenomena. Present practice is 
drifting away from the complete interruption of 
the antenna current which is the worst from an 
interference standpoint, but even the present 
methods of irregular and sudden variations 
of the current are still a long way from the 
possible scientific solution. 

"In 1915 the writer was considering t e 
general problem of improving the transmission 
system for submarine cables, and in connection 
therewith gave study to a new form of alphabet 
suitable to such a circuit. The system devised 
at that time may be described briefly as a 
continuous wave system: ' C. W. versus the 
' spark' system of the present cable practice. A 
method was developed of sending an unbroken 
alternating current through the cable, and 
means provided for interpreting this alternating 
current into intelligible signals. This system 
abandoned the Morse principle of different 
lengths of time for the signals as being funda- 
mentally inefficient, and adopted the plan 
that all individual signal units should occupy 



Can We Save Millions by Altering the Telegraphic Code? 



99 



equal lengths of time and have equal im- 
portance, whether they were dots, dashes or 
spaces. The signals were distinguished by 
varying the intensity of the individual sending 
elements, i.e., a dot, dash or space occupied 
equal time lengths, but were of different intensi- 
ties. The variation in intensity for signalling 
was effected at the transmitter at the zero phase 
of the resultant current flowing into the cable, 
so that, theoretically, at the moment of any 
operation upon the current there was no cur- 
rent to operate upon. 

"A point of fundamental importance in this 
method is that no two adjacent signals are of 
the same sign, since each semicycle is utilized to 
effect signaling, giving a dot, dash or space. 
Other things being equal, the variation in 
intensities for each of the three elemental 
signals are reduced to a minimum on the 
theory that the minimum possible change of 
the fundamental wave should be made. The 
reason for this is that an alternating current in 
the steady state, which amounts to a series of 
the present cable letters 'a' or 'n' strung to- 
gether without space, can attain a speed in any 
form of telegraphy many times greater than 
any practical system. A sinusoidal wave is 
transmitted through any form of electrical 
circuit without distortion of any kind, and, in 



fact, is the only type of wave that is so trans- 
mitted. 




ARE TRANSOCEANIC RADIO STATIONS WASTING MONEY WITH A NEEDLESSLY SLOW CODE? 

The photograph shows the towers of the Radio Corporation of America station at Rocky Point, 
Long Island, which communicates with England, France, Norway, Poland, Germany, and Italy 



IOO 



Radio Broadcast 



TABLE II 

COMPARATIVE SIGNALING SPEEDS OF INTERNATIONAL MORSE AND 

SQUIER ALPHABETS 

(Weighted according to the frequency of letters in telegraphic Eng- 
lish as given by Hitt, based on an actual count of 10,000 letters.) 

The following bases for comparison as regards spacing and length of signals are employed: 
(See page 22, Univeral Hectiical Communications Union, Washington, 1920). 



Element 


International 
Morse 


Squier 
Alphabet 


Dot 


i unit 


i unit 


Dash 


3 units 


i unit 


Space between parts of same character 
Space between letters 


i unit 
3 units 


o unit 
i unit 


Snace between words 


s units 


2 units 



Letter 


Signals 


Frequency 
in 10,000 


Units in 
Int. Morse 


Units in 
Squier Alph. 


Weighted 
Int. Morse 


\\Vighted 
Squier Alph. 


A 


.- 


813 


8 


3 


6504 


2439 


B 




49 


12 


5 


1788 


745 


C 





306 


'4 


5 


4284 


1530 


D 




4'7 


IO 


4 


4170 


1668 


E 




1319 


4 


2 


,276 


2638 


F 




205 


12 


5 


2460 


1025 


G 





20 1 


12 


4 


2412 


804 


H 




386 


10 


5 


3860 


1930 


I 




711 


6 


3 


4266 


2133 


J 





42 


16 


5 


672 


210 


K 





88 


12 


4 


1056 


352 


L 




392 


12 


5 


4704 


1960 


M 





273 


10 


3 


2730 


819 


N 


- 


718 


8 


3 


=i744 


2154 


O 




844 


14 


4 


11816 


337 6 


P 





243 


>4 


5 


3402 


1215 


Q 





38 


16 


5 


608 


190 


R 


._. 


677 


10 


4 


6770 


2708 


S 




656 


8 


4 


5248 


2624 


T 


- 


634 


6 


2 


3804 


1268 


U 




321 


10 


4 


3210 


1284 


V 




136 


12 


5 


1632 


680 


w 





166 


12 


4 


1992 


664 


X 




5i 


14 


5 


7'4 


2SS 


Y 





208 


16 


5 


3328 


1040 


Z 


. 


6 


'4 


5 


*4 


30 


TOTALS 


IOOOO 


292 


1 08 


9^534 


3574' 


Add for spaces between words, 






10,000 letters = 2,000 words 


3998 


'999 


GRAND TOTALS 


96532 


3774 


Average number of units per word 


48.266 


18.870 



= 48.a66 : 18.870 = 2.56 Squier Alphabet is 156% faster than International Morse 



Both tables were prepared under the direction of General Squier by Captain Friedman, Chief 
of the Code Section of the Signal Corps. It is the result of many months of research 



Can We Save Millions by Altering the Telegraphic Code? 



101 



Now 



'VMMM/HK 



The 



(A) Dot smallest amplitude. Dash medium amplitude. Spa e largest amplitude. 

(B) Space smallest amplitude. Dot medium amplitude. Dash largest amplitude. 

(C) Dash smallest amplitude. Space medium amplitude. Dot largest amplitude. 



Time 



There are three other possible permutations of amplitudes not shown 
of signalling units arbitrarily assumed as i: 2 

FIG. I 
HOW THE SQUIER SYSTEM WOULD WORK 



A STILL more important point to be con- 
sidered is the transmission of the largest 
volume of telegraphic business with a minimum 
number of signals, and from this angle the new 
form of alphabet has most striking advantages. 

" Fig. i illustrates graphically this method of 
modulating a single-frequency wave, and shows 
the words ' Now is the time' as they would be 
transmitted by this method, in which we 
arbitrarily assign the largest amplitude for a 
dash, the next size amplitude for a dot, and the 
smallest for the spaces between. 

It is well known that the sudden breaking or 
introduction of high impedances in an alternat- 
ing current circuit produces transient phe- 
nomena which results in a whole group of 
harmonics being transmitted. Add to this 
the practical condition of performing this 
operation upon a current ranging all the way 
from zero to hundreds of amperes, and it is 
easily seen that the ether of space is bombarded 
with a mass of frequencies never twice alike 
even in the same letter. It is little wonder, 
therefore, that no method has yet been devised 
to prevent such a disturbance from interfering 
radically with the reception of radio signals. 
Entirely apart, therefore, from a gain of more 
than 150 per cent, in the transmission speed, 
from an interference standpoint the present 
method is about as bad as it could well be. 

'At present the radio engineer has utilized 
and made his own all of the audio-frequency 
range and at least several octaves of the radio- 
frequency range, and has devised apparatus 
for the amplification and rectification of both 
of these ranges, audio and radio. This plan 



irgest . 

lere. Ratio of amplitudes 



proposes to enter the unused infra- 
audio range, which would not only 
add a most useful band of frequen- 
cies to those now used, but would 
give a band below the range of the 
human ear. If this band were em- 
ployed for telegraph, an additional 
advantage would be that it could 
not interfere with any radio receiv- 
ing. This method of eliminating in- 
terference would be most effective. 
" Finally, it is seen that by the 
method -proposed here it is possi- 
ble to modulate a single frequency 
by a number of modulating frequencies, and 
thus multiply the capacity of each radio fre- 
quency channel. 

"In 1921 the writer attended at Paris an 
international technical conference on outstand- 
ing radio problems, and for two months special 
delegates of the five great powers gave consider- 
ation to technical points connected with inter- 
national radio telephony and telegraphy. Such 
matters as interference, logarithmic decrements, 
disposition and allocation of wavelengths, 
radiation, etc., were considered. It is now 
proposed that the general subject of a suitable 
method for transmitting telegraphic signals 
either for radio, land lines or submarine cables 
be considered at the next international techni- 
cal conference, with a view, if possible, of 
unifying all branches of telegraphy using the 
same system of modulation for the signals." 

From all this we may rest assured that the 
next international conference which undertakes 
radio problems will devote much of its energy 
to a revision of the telegraphic code. It is quite 
possible that some effort in this direction will 
be made at the Pan American Congress to be 
held in Mexico City within the next few 
months. It will be well to consider General 
Squier's work very thoroughly. 

The radio amateur, whose transmitter and 
efficient receiver make it possible for him to 
chat with his neighbor over a distance of several 
thousand miles is beginning to feel the need for 
a universal language. He may well direct his 
effort to constructive work in revising his 
method of operation to conform with this more 
efficient vehicle and last but not least our great 
radio companies carrying on, as they do, about 
a quarter of our communication with Europe 
cannot afford to overlook the opportunity which 
General Squier points out as being capable of 
increasing their output by some 1 50 per cent. 



How to Build a Knock-Out Four 

Tube Set 

Incorporating with the Knock-Out One-Tube Reflex Receiver a 
Quiet, Inexpensive and Dependable Resistance-Coupled Amplifier 

By ZEH BOUCK 



THE outstanding characteristic of 
crystal rectified (detected) receivers, 
such as the single tube reflex set de- 
scribed with variations in recent is- 
sues of RADIO BROADCAST, is the good 
quality and clarity of the output. The re- 
markably clear tone reproduction of the crystal 
detector is due to the rectifying properties of 
the mineral, which delivers an audio-frequency 
current varying directly with the potential of 
the applied voltage. This is not the case in 
detection by the three-element vacuum tube. 
It is doubtful if this naturalness of tone will ever 
be improved upon, and the enthusiast who is 
satisfied with the volume of a single tube reflex, 
need search no further for perfection in de- 
tecting fidelity. 

However, it is difficult to preserve this clarity 
when amplifying in the conventional manner. 
This close approach to perfection cannot be 
carried through two ordinary stages of trans- 
former-coupled audio intensification. Though 
the output is still superior to that delivered by 
most amplified regenerative receivers, it has 
lost that subtle quality that stamped it as per- 
fect. This is particularly noticeable in ampli- 
fying the single tube reflex receiver, due to the 
capacitative feedback between the external am- 
plifier and the tuning unit. The measures 
taken to stabilize the whole, such as condensers 
connected to the amplifying grids and groun- 
ded, lessen am- 
plification and, 
in some particu- 
larly obdurate 
cases, tend to in- 
crease the distor- 
tion prevalent, if 
not inherent, in 
transformer- 
coupled amplifi- 
ers. 

The push-pull 
amplifier prob- 



TUBE"A' 




FIG. I 

Comparing the theories of resistance- and transformer-coupled 
audio amplifiers. There is not a great deal of difference 



ably represents the nearest approach to perfec- 
tion yet achieved in transformer-coupled audio 
amplifiers. 

THE RESISTANCE-COUPLED AMPLIFIER 

WHILE it is possible, in the laboratory, 
by means of certain balancing and cor- 
rective measures, such as the Campbell filter, 
to obtain perfect transformer-coupled amplifi- 
cation, the writer has never heard a two-stage 
amplifier with an output quality equal to that 
of a three-stage resistance-coupled audio in- 
tensifier. It is significant, that in many broad- 
casting stations, where perfect amplification is 
essential in the speech amplifiers, the simple 
resistance-coupled method is often used in 
preference to complicated transformer circuits, 
which their financial and laboratory resources 
make available. 

The reader will better appreciate the possi- 
bilities of the apparatus we are going to de- 
scribe, if, first, we make clear the theoretical 
functioning of such amplifiers, one of the most 
interesting of radio phenomena, quite easily 
comprehended. 

The resistance-coupled amplifier is not new. 
On the contrary, the chances are that it is the 
oldest form of amplifier, the system being prob- 
ably the direct and logical outcome of early 
experiments to determine the voltage ampli- 
fication of the three element vacuum tube. 

However, until 
the very recent 
advent of tele- 
phonic radio 
broadcast i n g 
during those 
twelve years 
when telegraphy 
was ninety-five 
percent, of wire- 
less, distortion- 
less amplifica- 
tion was actually 



How to Build a Knock-Out Four-Tube Set 



103 



undesirable, and so, without the 
recommendation of its predomi- 
nant and only advantage, the re- 
sistance-coupled audio amplifier 
was practically forgotten. The 
transformer-coupled type gave 
greater amplification per stage, 
particularly when the windings 
were designed to pass the narrow 
band of audio frequencies to which 
telegraphic tones were confined. 1 1 
is only now, after three years of 
redesigning and rewinding of the 
old code amplifying transformers, 
that the resistance-coupled amplifier is being 
salvaged from the radio junk pile. 

Fig. i is divided into two parts, showing am- 
plifying tubes coupled in two systems, A and 
B, respectively transformer-coupling, which we 
all know, and resistance coupling which, 1 
hope, the reader will soon know and appreciate. 

Amplifier A functions in a manner very easily 
understood. The plate current, set up by the 
potential of the B battery, flows through the 
primary, P, of the audio amplifying trans- 
former. This current is made to vary by signal 
impulses applied to the grid of tube A. When 
this current fluctuates, a potential, or voltage, 
varying with the strength of the plate current 
of tube A, is induced in the secondary winding. 
This secondary potential is applied to the grid 
of tube B that is, the voltage is impressed 
across the grid and filament. Condenser C, 
drawn in with dotted lines, is suggested in 




45 90 IZO 
FIG. 2 
he fundamental circuit of a three sfage~resistance-coupied amplifier 



order to make the action of circuit B clearer a 
little later on. The amplifier would function 
quite nicely with this condenser (about .0025 
mfd. or greater) in the circuit, but, as there is 
no necessity for it, we do not include it in the 
conventional transformer amplifier. 

We may therefore sum up amplification by 
stating that its requirements are a potential,* 
varying with the plate current of the preceding 
tube (A), which can be applied to the grid 
circuit of the succeeding tube (B). If we com- 
ply with these conditions, we have amplifica- 
tion. 

Bearing this in mind, we proceed to circuit 
B, which depicts two similar bulbs coupled 
by a resistance, Ri. Condenser C is placed in 
this circuit to isolate the grid from the high 



*This potential must, of course, exceed that applied to 
the grid of the preceding tube. The amplifying ability of 
the tube automatically takes care of this. 




FIG. 3 

The complete circuit of the receiver described in this article 



104 



Radio Broadcast 




FIG. 4 
Front view of the completed receiver. Only two tuning controls as usual 



plate potential. This circuit is quite similar 
to circuit A, though the unpracticed eye may 
not at first recognize the numerous relations. 
We have our plate circuit in tube A, from the 
plate, through the resistance Ri (instead of the 
primary of the amplifying transformer), the 
plate battery, and from there, down to the fila- 
ment. We also have our grid circuit the 
grid of tube B, through condenser C and down 
resistance Ri . Resistance R i is therefore com- 
mon to both the plate circuit of tube A and the 
grid circuit of tube B, acting more or less as a 
double substitute for primary and secondary 
of the audio transformer. Hence, if we can 
show that there is a varying potential across 
this resistance, which changes with the grid 
variation of tube A, we shall have established 
the fact that circuit B is an amplifying system, 
in which the functioning automatically becomes 
quite clear. 

Ohm's law states that the current is always 
equal to the voltage divided by the resistance 
I (current) equals E (voltage) over R (re- 
sistance), i. e., I = |r. Transposing, this very 
fundamental law also postulates that the vol- 



tage across any resistance 
is equal to the current 
times the resistance, in 
other words, E = I X R. 

E, in the case we are 
proving, will be the plate 
voltage; I the plate cur- 
rent; and R the coupling 
resistance, R i . The plate 
current varies with the 
grid potential of tube A. 
Thus, as the potential 
across Ri is always equal to the momentary 
value of the current times its resistance in 
ohms, this potential will vary directly with 
the grid impulses. That is, this circuit am- 
plifies. 

THE FUNDAMENTAL CIRCUIT 

FIG. 2 shows the fundamental circuit of a 
three stage resistance-coupled audio am- 
plifier. This amplifier is about equal to two 
stages of the best transformer-coupled amplifi- 
cation, as far as volume is concerned, and is 
noticeably superior to the best in quality. 
Its extraordinary purity of tone will be especi- 
ally noticed in the reproduction of a woman's 
singing voice. Barring any distortion at the 
transmitting end, the notes will come through 
liquid and pleasing, a marked contrast to 
some of the strident reproductions of the vocal 
attempts of a broadcasting coloratura soprano. 
The resistance of the coupling resistance, Ri , 
R3, and R$ varies in the opinions of individual 
experts, and also from the theoretically correct 
value (which is infinitely high). However, 
experience has indicated that 100.000 ohms is 
the best value when using the amplifying 




FIG. 5 

The panel layout for the Four-Tube Knock-Out 



How to Build a Knock-Out Four-Tube Set 



105 



tubes now available to the broadcast receiving 
public. 

It will be noticed that there are three sep- 
arate B battery taps one for detector (about 
forty-five volts, compensating for the extra 
plate resistance, Ri), the second (ninety volts) 
to the plate of the last tube, which circuit con- 
tains only the comparatively low resistance of 
the loud-speaker winding, and the third and 
highest voltage tap to the plates of the amplify- 
ing tubes through the high resistance coupl- 
ing units. Using the UV-2OI-A tubes, this 
voltage arrangement will result in approxi- 
mately the same total current consumption as 
a two step transformer-coupled amplifier, 
operating without a negative grid bias, and 
with ninety volts on the plate. Each amplify- 
ing tube with a plate coupling-resistance, will 
draw about one one-thousandth of an ampere. 

Considering the current consumption, as well 
as the extra tube and B battery, but balancing 
with the economy of coupling-resistances as 
compared with the cost of good amplifying 
transformers, the two systems break about 
even on an economic basis. (This is somewhat 
contrary to the general idea, which has always 
held the resistance-coupled amplifier to be a 
wasteful and expensive proposition.) 

Condensers C2, Cj, and C^ are included in 
the circuit, as before explained, to isolate the 
grid from the plus side of the B battery. Re- 
sistances R2, R4, and R6 are grid leaks, be- 



tween .05 and 2 megohms, the values of which 
are best determined by experiment. Expe- 
rience has demonstrated that while the grid 
leak value is not critical, there are many cases 
in which variation of this resistance will im- 
prove the tone quality of the received signal. 
One half megohm is about the average proper 
value. 

RESISTANCE COUPLING AND OUR ONE-TUBE 
REFLEX 

A 5 SUGGESTED early in this article.^ the 
single tube crystal detected reflex ' set, 
plus three stages of resistance-coupled audio- 
frequency amplification, is an ideal arrange- 
ment. The writer has effected this combination 
quite satisfactorily in the manner illustrated 
in Figs. 3, 4, 5, 6, and 7. 

Fig. 3 is the circuit followed in detail. Fig. 
5 is a plan of the panel. The remaining illus- 
trations are photographs of the completed re- 
ceiver. It will be noticed that two jacks and 
two rheostats, controlling the first two and the 
last two tubes, have been added to the funda- 
mental amplifying circuit. The jacks plug 
in on the first stage and last stage. Jack i will 
give powerful loudspeaker intensity on local 
stations, while J2 may be used for dancing in 
a medium size hall, and on distant stations. 
The last jack should never be used with tele- 
phone receivers. Signals so weak as to neces- 
sitate amplification are better enjoyed on a 




FIG. 6 

Behind the scenes. Rewound neutroformer- type coils are used as inductances. 
This simplifies mounting for the beginner by eliminating machine work 



io6 



Radio Broadcast 



single stage of amplification. Output binding- 
posts shunt the last jack when closed. 

THE PANEL 

A STANDARD panel was used 7" x 21". 
/V Figure 5 indicates the layout and drilling. 
All holes, excepting those with specially desig- 
nated sizes, are drilled to pass a No. 8 screw 
the diameter found on dry cells and large 
binding-posts. The appearance of the com- 
pleted receiver is greatly improved by graining 
the panel after drilling i. e., sandpapering it 
in one direction, and wiping with an oiled cloth. 

THE PARTS 

THE required parts are quite plainly shown 
on the diagram, Fig. 3, and are further 
listed in the following descriptions: 

Ti and T2, respectively coupler and R. F. 
transformer, may be wound by the experimen- 
ter as described in the " Knock-out Single 
Tube" article appearing in the April RADIO 
BROADCAST, or they may be neutroformer type 
coils with rewound primaries as suggested in the 
Laboratory Department of the June number. 
C<j and C6 are variable condensers with about 
17 plates, giving a maximum capacity of 
.00035 mfd. This capacity need only be ap- 
proximated. 

T3 is a good audio amplifying transformer 



having a turn ratio of about four or five to one. 
Observe the connection initials on the secon- 
dary. 

Det. is the crystal detector, preferably a 
fixed crystal such as the Erla or Star, or Celer- 
undum. 

R7 and R8 are thirty ohm rheostats. Three 
coupling resistances of 100,000 ohms each 
(Ri, R3, and R5), as well as three grid leaks 
(R2, R4 and R6) are necessary. These resis- 
tances will be treated in more detail later. 

Ci is a small bypass condenser, a Micadon, 
.0025 mfd. capacity. C2, C^, and G4 may be 
any convenient capacity Micadon between 
.0025 and .006 mfds., inclusive. The first ca- 
pacity was used in the receiver under discus- 
sion. Cj is a stabilizing condenser. A low 
capacity, .00025, or -0005 at the most, is very 
effective. 

Ji and J2 are standard double circuit jacks. 
Carter jacks were selected by the author for 
this set. 

The reader will observe from photographs 6 
and 7, that all condensers and leaks have been 
mounted in neat clips, which permit instan- 
taneous change of resistances and capacities. 
This is very desirable in the preliminary oper- 
ation of the apparatus. It is important that 
these mountings be of a reliable manufacture, 
with no resistance losses through the bases. 




FIG. 7 

Note the mountings into which the grid leaks and Micadons are clipped. 
These permit adjustments which are always desirable, and often necessary 



How to Build a Knock-Out Four-Tube Set 



107 



Daven mountings (Daven Radio Company, 
Newark, N. J.) were used for both condensers 
and grid leaks. Three grid leak mountings and 
four condenser mount- 
ings are required. 



Two neutroformer type coils with condensers 

Four General Radio* sockets 

One Amertran* audio transformer (5 to i 

ratio) 

Two General Radio* rheostats (20 ohms) 
One Pryatek*fixed crystal detector(see article) 

Two jacks 

Nine Eby binding-posts 

Two Pathe* dials 

Three grid leaks (see article) .... 
Coupling resistances (see article) at $5.00 
Three Daven grid leak mountings* 
Three Daven clip condenser mountings 

One panel, 7" by 21" 

Four Dubilier Micadons .0025 mfd. . 

Approximate cost 



BUILDING THE SET 

ALL instruments, 
excepting T i, Tz, 
T3 and the variable 
condensers, are 
mounted on the base 
board, which was a 
" board cut down to 

7|"X2I." 

The photographs 
show the back of 
panel layout. The 
sockets are mounted 
with the filament con- 
nections toward the 
panel. This arrange- 
ment makes possible 
the most convenient 
connections to grid 
and plate. 

The filaments are 

completely wired before the resistance and con- 
denser mountings, the jacks and inductances 
are placed in their respective positions. The 
amplifier is next wired, starting with the last 
step and running toward the antenna. The tun- 
ing units are last to be mounted and wired. 

Keep all wiring as close to the base as possi- 
ble. This makes for a neater appearance, more 
rigid wiring, and facilitates the clipping in and 
out of condensers and leaks. 

THE RESISTANCES 

RELIABLE resistances should, of course, be 
used throughout the receiver. However, 
reliability is to be particularly emphasized 
in the case of the 100,000 ohm coupling- 
resistances and the grid leak to the last tube 
(R6). 

The coupling-resistances may be any one of 
three possibilities. The Ward-Leonard resis- 



List of Parts Used in Making This 
Four-Tube Knock-Out Receiver 



$14.00 
4.00 

7.00 

2-50. 

1.25 

75 
.80 

.20 
.50 
I5.OO 
.20 
.20 

75 

2.OO 

$55.65 



*Other high grade makes may be substituted for 
the designated manufacture with equally good re- 
sults. 



tances obtainable from well stocked radio supply 
houses, are shown in the photographs, Figs. 6 
and 7. Lavite resistances, made by the West- 
ern Electric Company, 
and by the Crescent 
Radio Company, Ja- 
maica, N. Y. have been 
found equally satisfac- 
tory. The third possi- 
bility, and perhaps the 
simplest is to use a low 
resistance grid leak. 
This last, however, 
must be accurately 
measured for resist- 
ance, capable of pass- 
ing three milliam- 
peres, and must have 
a constant resistance. 
The writer has tested 
the Daven Radio Re- 
sistors (Daven Radio 
Company, Newark, N . 
J.) and found them 
quite equal for this 
purpose to the more 
expensive resistances. 

This particular make can be obtained in re- 
sistances from 50,000 ohms up. 

OPERATION 

TH E operation of the resistance-coupled am- 
plifier is quite consistent and as reliable as 
the transformer-coupled type. The only adjust- 
ments that may be necessary to secure the most 
efficient operation of the amplifier, is the change 
in the stabilizing condenser, C7 and the grid 
leaks (not the coupling resistances). 

If, on very loud signals, using the full ampli- 
fication, distortion or blasting is noticed, re- 
duce the resistances of the grid leaks in the last 
two tubes. In the receiver just described, the 
writer uses 2. meg., .5 meg. and .05 meg. in the 
respective cases of R2, R4, and R6. 

On local stations, it may be desirable to eli- 
minate the high voltage tap, operating all tubes 
at a plate potential of ninety volts or less. 



USING VARIABLE GRID LEAKS 

THERE are some variable grid leaks now on the market which have a minimum resist- 
ance of approximately 50,000 ohms and are capable of carrying the current in the plate 
circuit of a standard tube used in a resistance coupled amplifier. Variable grid leaks hav- 
ing a minimum resistance above 100,000 ohms, or incapable of carrying a plate current of 
approximately two milliamperes, should not be used as the coupling resistors, but any good 
variable grid leak may be used in place of the fixed grid leaks R2, R4, and R6. THE EDITOR. 



Some Remarks in Passing 



By J. P. McQUAIDE 

Vice President, Moon Radio Corporation 



RECEIVING distant stations depends 
greatly on weather conditions. If 
you receive many different stations 
one night and not the next, don't 
blame your set. If you do not think 
the trouble is in the weather, look at your bat- 
teries. They may be run down or one of your 
tubes may be losing sensitivity. As a gen- 
eral rule there is nothing in a radio set to 
wear out and once it is working satisfactorily, 
the trouble is usually in either the tubes, bat- 
teries or weather conditions. 

Don't use any higher voltage than is neces- 
sary on your B batteries, as the more voltage 
you use the faster your batteries will give out. 
Some people think that because their tubes 
light, they must be all right, but this is not al- 
ways the case, as the filament of your tube may 
light long after your tube has become defective. 
Every so often, it is a good plan to take out 
your tubes and clean the points. Good elec- 
trical contact is highly important in the tube 
socket. Particular trouble may be encoun- 
tered at the plate or grid socket contacts, and 
this is the hardest to find since even if the pins 
are not making contact, things look all right. 
ff you have just bought a set and you know 



it is of good manufacture, do not become dis- 
satisfied because you have not obtained the re- 
sults that some friend of yours is getting. 

I n large cities where there are many so-called 
dead spots, it is quite possible for a set to work 
much better in one room than it does in another 
due to the steel construction in the building. 
Try moving your set from one room to another, 
if you are not getting good results. 

A voltmeter for your B battery registering 
0-50 volts, and also a hydrometer, are good 
accessories to have around. 

Don't try to make a lot of noise with your 
set. Good clear reception with less volume is 
far better than reception with distortion and 
great volume. 

If you are getting good results from your re- 
ceiving set, write and tell the manufacturer. 
He will be very glad to know it. If you are not 
getting the proper results, he will want to know 
that too. Perhaps he can help you. 

Receiving sets are becoming easier to operate, 
and the manufacturers are doing all in their 
power to help you enjoy radio concerts. Re- 
ceivers are not automatic, however, and should 
be given some care and not knocked around 
from place to place. 



ERITABLE multitudes of radio listeners in the eastern and central parts 
r of the United States who count that Sunday lost when they do not hear 
"Roxie" and his gang from the Capitol Theatre, New York, will be much in- 
terested in James C. Young's excellent story about "Roxie" (S. L. Rothafel), his 
gang, and his theories, which we will print in July. 



What's in a Name? 

A Brief Guide Book to the Radio Gallery of Names, Telling Why 
"Dynes" and "Flexes" Need Not Be Greek to Almost Everyone 

By JULIAN KAY 



If you are new to radio or at least a present stranger to radio theory, the series by Zeh Bouck, "Va- 
rious Circuits and What They Mean" is well worth consulting. In this magazine for December, 1923, 
appeared the first of his articles on How to Analyze a Diagram. In January, 1924, Mr. Bouck's article 
explained what inductance is and how it is used. The February article^ explained how radio circuits 
are tuned. "What Makes the Wheels Go 'Round" W. Van B. Roberts' serial explaining radio theory 
should also be consulted. It began in March. 



OALL the pests the worst is 
probably the chap who has a 
positive mania for radio. He 
follows you around talking 
about super this or dyner that. 
He has a habit of pushing you into a corner to 
tell you of the latest tricks he has played on his 
Neutroreflex. He knows more circuits than 
you can shake a stick at; he eats, sleeps, and 
orates radio. 

Do you know this 
chap? He is always 
worrying about his 
plex, or his auto, or 
his dingus circuit. He 
rushes madly from 
one radio fad to an- 
other, speaking hazily 
about "quality" or 
"radio-f req." His 
usual conversational 
ability can be meas- 
ured by: 

"Say, I tried out 
those Fussyform coils 
on my Superwhoosis 
last night. 1 had 
twenty-eight turns of 
double covered green 
silk magnet wire on 
the secondary and a 
double naught two 
five condenser 
across ' and so on 
ad libitum until you go. 

Suppose for instance that you were a master 
of the violin, that you loved your instrument, 
that you knew it better than anything else. 
Suppose that you had made it a lifelong com- 
panion, that it soothed and piqued you and 



What Does That Mean? 



Is an often repeated question addressed to 
those who know and those who seem to know, 
more than the rest of us about radio. The 
answer may be correct or it may be some hazy 
attempt at explanation that leaves the ques- 
tioner in a greater confusion and uncertainty 
than ever. And when the question turns to 
receivers and their names, well indeed can 
the question be "What Does It Mean?" 
There are many who recite the various name- 
tags glibly, knowing precious little whereof 
they speak. 

This article attempts to sort out and classify 
the receivers in present use, to show what they 
are, and how they are electrically related, and 
what they are designed to accomplish. No 
effort is made to give a technical or even popu- 
lar explanation of their working, for that is 
task enough for a book. This series aims to 
cast at least a faint light in the present dark 
forest of ponderous hyphenated radio names. 

THE EDITOR. 



gave you immeasurable joy and pleasure. With 
fellow devotees of the violin you shared your 
secrets and your dreams. 

And then some morning suppose that you 
found everyone talking of your violin in the 
most off-hand fashion, not as the instrument 
that you loved but as a "fiddle"; and that 
people seemed more interested in the fact that 
it was made of Spanish cedar and LePage's glue 

than in the beautiful 
tones with which it 
responded to your 
touch. 



SUPER-FIDDLES AND 
FIDDLE-DYNES 



S 1 



UPPOSE even, 
that the big 
brothers of the violin 
were mentioned as 
super-fiddles and fid- 
dle-dynes instead of 
their proper names; 
that everyone could 
play them as easily as 
though they were tin 
horns; that everyone 
talked in the most glib 
manner about species 
of violins of which you 
had never heard. 

In fact, if you sud- 
denly awoke to the 
fact that your hobby 
was no longer an in- 
dividual affair, but that the whole world owned 
it, a world that thought you out of date how 
would you feel about it? 

Do you see how the old timer in radio feels 
about all this business of names, and new 



I IO 



Radio Broadcast 




Antenna 
circuit 



Three circuit receiver 
Figure 1. 



circuits, and the smug acceptance with which 
radio is viewed to-day? 

Or, if you are a new comer, are you be- 
wildered by the claims of the various dynes and 
plexes and supers and the personal monuments 
like the "Jones" or the "Smith" circuits? 

To classify the types of receiving circuits now 
being used, the Family Tree on page 1 12 may 
be useful. It will be seen that there are three 
broad groups of radio receiving equipment, and 
it may be said at once that all of the modern 
types may be found there, or may be a hybrid 
product of two or even all three of these groups. 
So when your friend says that he had a new 
circuit see how it fits into the Circuit Family 
Tree, and if it cannot be found there, if it is not 
a detector or an amplifier, rush your friend to 
the patent office, for he has something the world 
needs. 

ALL RECEIVERS MUST BELONG TO ONE OF THREE 
CLASSES 

THESE three great groups into which all 
receiving equipment naturally falls are 
dependent upon each other, and a really good 
outfit is a proper combination of apparatus 
from each of the groups. The name it bears is 
no criterion of its effectiveness as a receiver. 
Indeed "a rose by any other name would smell 
as sweet." 

The first requisite for a receiving set is a 
detector serving the same purpose as our own 
physical organs for "detecting" the sounds 
that exist in the air, organs we call ears. Now 
everyone knows that there are sounds that are 
too weak for us to hear, and that we can 
remedy our inability to detect these minute 
sounds by proper means of magnification, say 
by an ear trumpet. If our human organism 
possessed a device between the ear and the 
brain for again amplifying the sounds that the 
ear detects, we would have a more or less 



complete analogy for the three groups of radio 
receiving equipment. 

Radio-frequency amplifiers magnify the in- 
coming energy before it is passed through the 
detector, and following the detector, come 
audio-frequency amplifiers which again magnify 
the energy. 

ABOUT DETECTORS 

DETECTORS naturally fall into two classes, 
non-regenerative and regenerative. The 
first group comprises the simplest of all receiv- 
ing circuits. Crystal detectors are very old, 
going back to the earliest days of wireless 
telegraphy. The simple audion connection 
was used for a considerable time before Arm- 
strong demonstrated his remarkable discoveries 
leading to the regenerative detector. 

The last two years have seen the advent of 
vacuum tube detectors on shipboard, but on 
many vessels at the present time, the operators 
still wrestle with old "catwhisker" crystals. 
Among the amateurs, however, the crystal 
of the past few years, is as good as dead, and 
would be completely out of date to-day were it 
not for the recent, broadcasting development. 

The non-regenerative detectors are marked 
by certain inherent disadvantages, but con- 
trary to common opinion have other advant- 
ages which are becoming more and more im- 
portant. 

A crystal or simple non-regenerative tube de- 
tector without some means of amplification will 
not respond to signals from very great distances 
nor will it give much volume. On the other 
hand, the quality of music or speech pro- 
duced by such a detector is far better than the 
usual regenerative equipment is capable of 
producing, particularly when handled by one 
unaccustomed to tuning it. With a stage 




What's in a Name? 



1 1 1 



or two of radio-frequency amplification to 
boost the incoming energy, and a stage or two 
of audio-frequency amplification to bring up 
the signals to the required volume, a simple 
non-distorting detector is unequalled. 

The outstanding features representative of 
this group are, that they are 

1. Non-distorting. 

2. Of low cost. 

3. Capable of short distance reception. 

4. Of low upkeep. 

5. Simple. 

6. Non-selective. 

7. Non-radiating. 

The principles underlying the regenerative 
receiving circuits are the foundations upon 
which present day radio is built. Were it not 
for what vacuum tube experts call " regener- 
ation" whence comes the name of these 
receivers radio broadcasting would probably 
not exist to-day. 

WHERE THE VACUUM TUBE COMES IN 

THIS discovery seems simple in the light 
of our present knowledge. Suppose we 
have a device that has more energy in its out- 
put than in its input circuit. If some of this 
excess energy is fed back into the input, it will 
reappear at the output, amplified by the action 
within the device. If the excess output is 
sufficient to make up for the losses due to re- 
sistance in the circuit, continuous oscillations 
are built up and we say that the system "oscil- 
lates." 

The immediate result is a remarkable in- 
crease in signal strength due to the fact that 



Antenna 

circuit 





Q-JAL 





Single circuit receiver 
Rqune 3 



regeneration is apparently a method of de- 
creasing resistance to a very low value, which 
permits large currents to flow. Another im- 
portant result is the increase in selectivity also 
due to the lowered effective resistance. 

In general it may be said that regenerative 
receivers are highly sensitive, reasonably selec- 
tive, giving considerably greater strength of 
signals than non-regenerative detectors. On 
the other hand, this type of detector is critical 
in its adjustment, is likely to distort so that 
music and the voice are not reproduced accu- 
rately and pleasantly. The great objection to 
this type of detector is its certainty to disturb 
fellow listeners by its self radiation unless care- 
fully handled. 

At the present time the tendency seems to be 
away from regenerative detectors and toward 
radio-frequency amplification, so that the 
future may see the birth of new receivers 
utilizing other methods of detection giving the 
same sensitivity but none of the distortion or 
interference defects of regenerators. The 
Sodion tube is a decided step in this direction. 

ONE WAY "NEW CIRCUITS" AND "NEW" NAMES 
START 

IN ACTUAL practice the plate circuit (out- 
put) is coupled back to the grid (input) 
either through a resistance, an inductance, or 
by means of a condenser. In fact if the experi- 
menter is ambitious and wishes to combat all 
manners of coupling he may use combinations 
of all of these methods. And each time that 
someone "discovers" anew these coupling 
methods a new name is given it. 

It will be noticed that the chart divides 
regenerators into several groups depending 
upon the complexity of the equipment. Any 
complete receiving set must comprise three 



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What's in a Name? 



radio-frequency circuits: the antenna and 
ground, the secondary or input of the detecting 
device, and the output. If the output is not 
tuned, that is, if there is no attempt to resonate 
it with the radio-frequency signals, the system 
becomes a two-circuit tuner. If the antenna 
to ground circuit is combined with the input, 
the combination is known as a "single circuit" 
receiver. 

Of the latter, RADIO BROADCAST has already 
said plenty. This receiver is like the neighbor's 
dog that howls under your window at the moon. 
It causes the horrendous squeaks and howls; 
the little fellow around the corner that swishes 
across your wave, breaking into your concerts, 
and offending your musical ears. In England 
it is unlawful to do anything with one of these 
outfits except, as someone has suggested: 

"Use it as an anchor." 

On the circuit Family Tree they are enclosed 
in a black box of mourning and they should 
be dead. 

WHY THE MULTI-CIRCUIT SETS ARE GOOD 

THE two-circuit tuner is a great improve- 
ment over the single circuit owing to its 
greater selectivity. 

The three-circuit outfit in which the plate 
radio-frequency path is also tuned is naturally 
the most efficient of all, for oscillations occur- 
ring in this circuit may be controlled a 
feature which the simpler systems do not 
possess. In connection with this type of 
equipment it must be said that close coupling 
between the antenna and secondary circuits 
may produce just as malignant interference to 
one's neighbor as any improperly operated 
single circuit regenerator. 

In these various schemes, it does not matter 
whether an inductance or a condenser is used 
for the feed back or the tuning, the process is 





Armstrong flivver circuit 



Weoqant X circuit 

Figure & 



one of obtaining resonance or of conveying 
energy from one circuit to another. For 
instance the "X" circuit in which the plate 
is tuned with a fixed coil in series with a variable 
condenser in place of the usual variometer is 
still a tuned plate arrangement. 

In fact the capacity element of a complete 
radio path may not be apparent at all, but may 
exist within the tube, or as distributed capacity 
of windings, or as the capacity of the antenna 
to ground. 

The ultra-audion has the input circuit at- 
tached directly to the plate; the " tickler" outfit 
uses a coil in series with the plate and placed 
near the grid coil to affect the feedback; the 
Reinartz employs a condenser between grid and 
plate and there you are. They all do the same 
thing but in a different way. 

The Four-Circuit tuner is apparently an 
adaptation of the ultra-audion in which an extra 
absorption circuit is placed near the grid 
inductance. The idea is to extract enough 
energy from that circuit to prevent oscillation 
with its accompanying distortion. It is better 
than the straight ultra-audion on this account. 

The Reinartz circuit was developed by a 
prominent amateur for use in receiving continu- 
ous wave stations operating on short wave- 
lengths. It is most eificient when the tube 
oscillates, and is simple to adjust. The feed- 
back control is nicely adjustable. 

When improperly handled it has a tendency 
to radiate. 

SUPER-HETERODYNE AND SUPER-REGENERATOR 
ARE THE ONLY NEW DEVELOPMENTS 

THE latest application of regeneration, the 
super-regenerator is a member of the type 
of detector under discussion. The principle 



Radio Broadcast 



P 
O 



, m 


JAL. 




o 


H 


i 




is rather unique and the development of this 
system marks the only "new" thing that has 
appeared since the super-heterodyne. 

As any one knows who has operated a 
regenerative receiver, the most sensitive operat- 
ing condition is at the point where the tube is 
about to break into actual oscillation. Many 
schemes might be devised for actually letting 
the tube oscillate a small fraction of a second, 
and then to shut it off. This is what was 
actually accomplished in the super-regenerator. 
As usual there are several methods of carrying 
out this idea, and many of the "trick" circuits 
that exist to-day may be traced to some obscure 
super-regenerator function. 

I n practice, this type of receiver proves to be 
noisy and critical, and it is one of the most 
powerful radiators. It has not proved to be of 
great value in the reception of music, although 
it is useful in code receivers. 

Without a doubt the regenerative receiver is 
one cf the most sensitive and efficient devices 
ever discovered, but its use in radio seems 
limited to the time when equally efficient radio- 
frequency amplifying systems are developed 
schemes which will be discussed in a future 
article. Under this head fall the neutrodyne, 
the superdyne, and the super-heterodyne. 

In order to get sufficient energy from any 
type of receiving equipment to operate a loud 
speaker it is necessary to use one or more stages 
of audio-frequency amplification. To increase 
the range of a given receiving set, a stage of 
radio-frequency amplification may be added 
before the detector, and when one adds this 
equipment it is a fairly simple matter to make 
the extra vacuum tube do double duty in 
other words to reflex it. Reflex systems in 



which the audio and radio amplifiers are com- 
bined are the most economical arrangements 
used to-day, and as usual are of several varie- 
ties, each with a different name. This group 
will be discussed in subsequent articles. 

ABOUT RADIO-FREQUENCY AMPLIFICATION 

MANY names have been applied to the 
many schemes for amplifying radio- 
frequency energy. Sometimes these names 
signify what is going on in the device, but 
usually they are colorful handles added to 
otherwise colorless circuits. It is much easier 
to invent a new name for an old circuit, than 
to invent a new circuit. The next article 
in this series will develop the radio-frequency 
family tree, and show how the various methods 
work. 

By properly designing a radio-frequency am- 
plifier and carefully neutralising it, one can add 
considerable volume to the signals. This is 
contrary to the common supposition that a 
noticeable addition of volume can only be at- 
tained by audio-frequency amplification. The 
two-tube receiver described in RADIO BROAD- 
CAST for April and May is an excellent ex- 
ample of what one can do with a small amount 
of equipment. Here is a detector, a radio- and 
an audio-frequency amplifier, a "neutrodyne" 
and a "reflex" all with two tubes. 

In following articles in this series, the vari- 
ous circuits which involve the use of radio- 
frequency amplification will be discussed. The 
radio newcomer should preserve these circuit 
"family trees", for they will help him analyze 
the many circuits which plague his bewildered 
eye. 




The Inside Story of the British 
Broadcasting Experiments 

How Success Came After Many and Long Experiments to Link 
America and Great Britain, by One of the Staff of 2AC at Manchester 

By W. J. BROWN 



Metropolitan-Vickers Company, Manchester 



SO MUCH interest has been aroused by 
the recent American rebroadcasting 
tests that the following account of the 
preliminary experimental work which 
was necessary before the tests could 
be conducted should 



be of some interest. 
It is probably not gen- 
erally realized that the 
relaying of KDKA, 
the Pittsburgh station 
of the Westinghouse 
Electric & Manufac- 
turing Company, was 
only rendered possible 
by a tremendous 
amount of experi- 
mental work between 
this Company and the 
Metropolitan - Vickers 
Electrical Company of 
Manchester. There 
was no mystery about 
the excellent results 
which have been ob- 
tained on 100 meters. 
These were in fact the 
culmination of plans 
which were made 
many months ago. 

The Metropolitan- 
Vickers Company is in 
very close technical 
association with the 
Westinghouse Com- 
pany, and several 
months ago it was 
agreed that a combined attempt should be 
made to relay the KDKA broadcasting pro- 
grams in this country. The Westinghouse 
Company had been experimenting with short 
wavelengths around 100 meters and had found 
that they promised well for long-distance 



reception, though of course this is all against 
the theory of excessive absorption on short 
wavelengths. In September, 1923, they com- 
menced experiments with the Metropolitan- 
Vickers Company by transmitting their or- 
dinary broadcast pro- 



The Future Which Way? 

It is manifestly impossible for every radio 
listener to own a highly sensitive receiver. 
And it is also true that as radio grows older 
broadcasting will be more used in politics, in 
government, and all branches of the national 
life. So it is that the long-visioned ones in 
radio have wondered how it is economically 
and electrically possible to bind together some 
of our powerful and important broadcasting 
stations located at strategic points in the 
country, so that an event of national import- 
ance could be broadcast nationally. Most of 
our readers know of the recent successful 
experiments which have taken place within 
the last six months. 

Now there are two ways to link broadcast- 
ing stations. One is by direct land wire, and 
the other is by radio itself, using extremely 
short wavelengths. In this country, the 
American Telephone and Telegraph Company 
has done much with the land line method 
while the Westinghouse Electric and Manu- 
facturing Company has taken the opposite 
course and done a great deal of research with 
transmission over long distances with short 
waves. We described these experiments 
from the American angle in our February 
number. This is the English side of the story. 

THE EDITOR 



grams on 100 meters 
as well as on their nor- 
mal broadcast wave- 
length of 326 meters. 
The Metropolitan- 
Vickers Co. built up a 
i oo meter receiver and 
listened to the trans- 
missions at their ex- 
perimental station at 
Altrincham in Che- 
shire. 

WHAT IOO METER 
WAVES WOULD DO 

TTWASimme 




1 apparent^ 
loo mettf^tnlhsrms- 
sions came over the 
Atlantic better than 
the 326 meter wave- 
length. The chief im- 
provements noticed 
were firstly, greater 
consistency of results, 
secondly, freedom 
from interference by 
spark stations/'mush" 
and static, and thirdly, 
the comparatively 
small amount of fad- 
ing experienced. As regards consistency of 
results, the improvement was particularly 
noticeable, and it was found possible to receive 
signals much earlier in the night than was 
possible with the 300-500 meter American 
transmissions. 



n6 



Radio Broadcast 



The experiments being so far successful, the 
Westinghouse Company built a new transmit- 
ter operating at nearly 30 kilowatts input. 
This transmitter represents absolutely the 
latest radio engineering practice. It employs 
special high-power tungsten valves with an 
elaborate system of water-cooling, whereby 
quite a small valve can be made to handle an 
enormous amount of power. Most elaborate 
precautions are taken to prevent slight changes 
of wavelength which at the exceptionally high 
frequency of 3,000,000 cycles per second 
would have a very serious effect. The antenna 
system is designed to have absolute rigidity, as 
are the high frequency connections of the trans- 
mitter itself. The inductances are wound on 
rigid formers and as a final precaution the 
whole of the high frequency portion of the 
transmitter is mounted in a framework sus- 
pended by springs. 

Statements have recently appeared in the press 



to the effect that KDKA has been making 
no special effort to broadcast their signals over 
the Atlantic, and also that their 100 meter 
transmission is of lower power than that of a 
British Broadcasting Company station. When 
it is realized that KDKA has been working with 
Metropolitan-Vickers for months past, and 
that they built a transmitter specially for 
transatlantic work which is probably greater in 
power than all the British Broadcasting Company 
stations put together the inaccuracy of such 
statements will be appreciated. 

The first tests on the new transmitter were 
made in October, 1923, and naturally it was 
found that signals were coming over a good bit 
more strongly than before. Other troubles 
became evident however, chief of which was 
"night distortion" which is caused by slight 
changes in the carrier frequency of the trans- 
mitter, together with changing propagation 
conditions. In many cases this distortion was 




WHERE AMERICAN BROADCAST PROGRAMS ARE HEARD ALMOST NIGHTLY 

The extremely sensitive receiver at the Trafford Park Laboratories of the British Broadcasting Company near Manchester. 
The six foot loop in the foreground is used constantly in receiving 94 meter waves from KDKA, and, recently, the 104 
meter wave of WG Y. A wire line connects this station with the operating room and studio of the Manchester station 2 AC 



Inside Story of the British Broadcasting Experiments 



117 



so bad that speech was rendered quite unin- 
telligible. 

It must again be emphasized that, working 
with wavelengths as short as 100 meters, a 
very much greater constancy' of wavelength 
is required than with the 300-500 meter trans- 
missions, and also this constancy is much more 
difficult to obtain. 

Many experiments were carried out with a 
view to eliminating this trouble. These ex- 
periments were carried on usually in the 
early (or rather, late) hours of the morning 
after the American broadcast program had 
ceased, and special forms of modulation were 
employed for the purpose of analyzing the 
effect. Great difficulties were met, parti- 
cularly at the transmission end, and these 
resulted in an almost continuous flow of cable- 
grams between the two 
companies. In the end, on 
December 27, 1923, a 
fairly good transmission 
through was achieved, and 
on the following day re- 
broadcasting of KDKA to 
listeners in Great Britain 
was an accomplished fact. 

During ; the following 
seven or eight days the 
Metropolitan-Vickers Com- 
pany carried out a series of 
rebroadcasting tests, so as 
to gauge the possibilities of 
their system as it ,then 
stood. The repeating was 
done from the Company's 
station 2AC at their re- 
search laboratories, Traf- 
ford Park, Manchester. An 
experimental i| kilowatt 
transmitter was employed, 
operating at a wavelength 
of 400 meters. Reception 
was still carried out at the 
Altrincham Station. The 
two stations were connected 
bv land-line. 



mine the most satisfactory method of reception. 
During the whole of the relaying period, how- 
ever, a frame aerial some six feet square was 
used for picking up the signals while the receiv- 
ing set employed a number of high frequency 
stages varying from six to twelve according to 
the prevailing conditions of reception. After 
detection, the signals were passed through two 
stages of low frequency power amplification 
before passing them on to the line leading to 
the microphone transmission. 

At the beginning of the week, the whole of 
the controlling and ^announcing from Altrin- 
cham was done over telephone lines, but this 
was found to be rather unsatisfactory since 
there was no suitable non-resonant room for 
speech purposes at the Altrincham station; 
hence these functions were transferred to 




THE MANCHESTER EQUIP- 
MENT 

DURING the preceding 
two months many dif- 
ferent forms of receiver and 
various antenna systems 
had been tried out, to deter- 



Barratt's, London 



CAPTAIN A. G. D. WEST 



Assistant chief engineer of the British Broadcasting Company. Captain West has 
supervised the successful rebroadcasting of American programs from WGY and KDKA 
on a number of occasions. "We have some difficulty in regard to distortion," says 
Captain West, "The announcer is usually quite intelligible, but in some speeches, 
not a word can be understood, and this is perhaps when they are an "outside broad- 
cast" . . . One of our chief troubles is from French amateur transmitters work- 
ing on about 100 meters. Some of them spend their time tuning up and down for 

hours on end" 



n8 



Radio Broadcast 



Trafford Park before the end of the week. 
In order to keep a check on the quality of the 
landline tranmission from 2AC, a 400 meter 
receiver was rigged up at Altrincham. The 
"control operator" was equipped with a pair 
of phones which he could connect at will either 
to KDKA direct or else to KDKA via 2AC 
and thus he could immediately detect any 
transmission or line faults. 

A portion of the receiving station is shown 
in the accompanying photograph. The frame 




THE NINE BRITISH BROADCASTING STATIONS 
are connected by land line to the central London station 

antenna is seen in the foreground. Behind, to 
the left, is seen the control and announcing 
table and the low frequency amplifiers. Im- 
mediately behind the frame antenna is seen 
one of the receiving sets. 

During the period of approximately one 
week the Metropolitan-Vickers Company suc- 
ceeded in relaying the Westinghouse trans- 
missions for an aggregate time of 18 hours. 
In two or three cases relaying commenced about 
11.30 Greenwich Time, but the best results 
were undoubtedly obtained between the hour of 
4 A. M. and j A. M. as had been anticipated from 
previous results. In fact one or two of these 
early morning transmissions were almost perfect 
in their reproduction nearly as good as a first 
hand broadcast transmission. 



ARLINGTON SIGNALS TWICE RETRANSMITTED 

DURING the week a complete American 
program was successfully relayed right 
from the first item by the Westinghouse 
Band at 1 1 120 p. M. up to the relaying of the 
Arlington time signals at 3:00 A.M. The re- 
laying of the Arlington time signals was in 
itself something of a novelty, since it reached 
the ears of British listeners through no less 
than three stages of transmission. The signals, 
which are the American equivalent of the 
famous Paris time signals, were transmitted 
from Arlington on a wavelength of 2650 
meters at 10:00 P.M. New York time. They 
were picked up by the Westinghouse Company 
at Pittsburgh, 200 miles distant, and sent over 
the Atlantic to Manchester on the 100 meter 
wavelength, who received them and trans- 
mitted them for the third time on their 400 
meter wave at 3:00 A. M. Greenwich Time. 
(Greenwich time is 5 hours later than that in 
New York). 

Anxious to obtain all possible information 
and experimental data concerning the relaying, 
the Metropolitan-Vickers Company asked for 
reports, and got them. They were numbered 
first by hundreds and then in four figures. 
With scarcely an exception, they were all com- 
plimentary, most of them enthusiastically so. 
Many of these reports came from the Contin- 
ent, some of them from as far off as Switzer- 
land and even Italy. When it is considered 
that the power input at 2AC is somewhere 
about half the average power of a British 
Broadcasting Company station and that the 
actual relaying of KDKA was clearly heard at 
these distances, the results of the experiments 
were very gratifying. It has been possible to 
reply by post to only a very small percentage 
of the reports received, and the Metropolitan- 
Vickers and Westinghouse companies would 
like to take this opportunity of recording their 
thanks to all those listeners who have been 
good enough to send in their reports and 
comments. 

A few details of the ordinary broadcasting 
activities of the Westinghouse Company may 
be interesting. In November, 1920, they 
opened the pioneer broadcasting station of 
the world, KDKA, at East Pittsburgh. The 
first transmitter was of comparatively low 
power i oo watts were delivered to the antenna. 
This was increased by stages to its present 
value of looo antenna-watts, corresponding to 



Inside Story of the British Broadcasting Experiments 



a D. C. input of four or five kilowatts. The 
main studio at KDKA is situated half a mile 
from the transmitting station. There are also 
two other studios in the city, 14 miles distant, 
all of which are elaborately equipped. Land- 
line transmissions are an important feature; 
there are 45 permanent landlines covering an 
area of 225 square miles. These take in every 
church, theatre, public hall, and auditorium of 
any pretensions in the Pittsburgh section. 

SOME CONCLUSIONS ABOUT SHORT WAVE BROAD- 
CASTING 

IN CONCLUSION it is interesting to compare 
the results obtained with this 100 meter ex- 
perimental transmission with those which 
might be expected with the ordinary 300-500 
meter American broadcasting. As indicated 
earlier in this article it proved possible to relay 
the too meter signals for 18 hours during little 



more than a week, whereas in all probability 
sufficiently good reception of the 300-500 meter 
signals for relaying purposes would not be 
obtained for more than 2 or 3 hours per week. 
Thus it may be claimed that these experiments 
with the Westinghouse Company have in- 
creased the chances of American relaying 
probably about ten times. Also they have 
rendered it practicable to start such relaying 
at about 1 1 :oo P.M. during the winter months, 
as compared with the impossible hour (for 
most people) of i :oo or 2 :oo o'clock in the 
morning. 

Of course perfection is not nearly reached, 
but some of the greatest difficulties which 
existed have been largely overcome, and with 
further developments the relaying of intelli- 
gence and entertainment from America may 
in the fairly near future become a matter of 
everyday fact. 




Keystone 

THE HOTEL SAVOY BAND 

-a well known dance orchestra from a well known London hotel, whose excellent programs have been broadcast for the 
especial benefit of American listeners from 2 LO and the other eight BBC stations 



'stenoriPoint 



Conducted 

by 

bnnie Irene M* 




WKat Does the Public Want in Radio Music? 



BROADCAST directors seem to be 
losing much sleep worrying over the 
question, "What does the public 
want in radio music"? In their 
well-intentioned attempts to find a 
solution to this problem they send out question- 
naires, or they ask at the end of a program if 
the listeners will please be so very kind as to let 
it be known 

by letter iMttBBBHtiHMBiiBHHHI 
what num- 
bers they 
most enjoy- 
ed. "Only 
through such 
means,' 
comes the 
explanation , 
"can we give 
you what 
you want." 

One would 
think from 
this that 
until radio 
came into 
existence the 
American 
public had 
given no in- 
dication of 
what it 
wants in mu- 



IGNAZ FRIEDMAN 

lo hear such an artist as Mr. Friedman over the radio wipes out the memory of 

many mediocre performances sent through the air. The New York recital of this 

internationally famed pianist was broadcast by station \VEAF 



sic. On the contrary this question was quite 
definitely answered so many people believe- 
long before a broadcast station was thought of. 
In order to find a partial answer, broadcast 
directors might examine the attendance of 
concerts and opera and thus find out what kind 
of music the public pays to hear. They might 
well listen ... as one among these audi- 

ences and 
note how the 
music is re- 
Nj| ceived. 

Through 
these means 
an idea can 
be gained of 
what large 
numbers of 
people want 
in radio 
music. For 
one's mu- 
sical taste 
does not 
change sim- 
ply by tun- 
ing-in a re- 
ceiving set. 
Many people 
listen over 
radio for the 
same kind of 
music that 




Unde 



d \ I nde 




Nicholas Muray, New York 
EVA LE GALLIENNE 

This picture shows this famous young actress as she appears in "The Swan" at the Cort Theater, New York! Miss Le 

Gallienne was recently introduced to a radio audience through station WOR. After giving a short talk, she read some of 

the most widely known of the poems written by her father, Richard Le Gallienne. From the picture, one concludes that 

those who could hear but not see Miss Le Gallienne lost as much as they gained 



122 



Radio Broadcast 



they have long enjoyed through the established 
concert channels. 

To facilitate knowledge of what sort of music 
a large public pays to enjoy, here are some 
facts. 

There are in this country ten or a dozen 
permanently established symphony orchestras 
of the first rank, maintained solely for the pur- 
pose of presenting only the best in orchestral 
music supplemented at times by soloists cap- 
able of playing or singing works of a standard in 
keeping with the rest of the program. There 
are about forty other orchestras maintained for 
the same purpose and all steadily advancing 
into the same rank. This means that in fifty 
or more cities, and in the communities adjacent 
to these cities, there is a 
public eager to hear the 
greatest music ever 
written. For the fore- 
most instrumental 
works of the worlds' 
foremost composers 
may be found in or- 
chestral literature. 

To hear these or- 
chestras and other mu- 
sical attractions of equal 
standard the American 
public spends more each 
year than for attend- 
ance at all the sports 
combined, even includ- 
ing those years when 
championship prize 
fights are staged. 

The music students 
who are scattered all 
over the country pay 
millions of dollars 
yearly for serious 
musical instruction. 
Their teachers add to 
the aggregate of these 
figures by themselves 
spending money to 




study whenever pos- 
sible under the great concert artists who, at 
stated periods, conduct master classes. 

There is scarcely a college of any importance 
throughout the entire land that does not main- 
tain a music department. 

In well nigh every city, and also in large 
numbers of towns, pupils in the public schools 
are given opportunity to study music under 



Moffett, Chicago 



CLAUDIA MUZ1O 

One of the greatest among living operatic sopranos and 
now with the Chicago Civic Opera Company. She has 
been heard in solos over the radio and affirms that 
she enjoys singing for her unseen listeners as much 
as they seem to enjoy hearing her, judging from the 
letters she has received from these listeners. Mme. 
Muzio's broadcast performances have been given at the 
Zenith Station now operated by the Chicago Tribune 
(WGN) 



expert instruction, this study including also 
classes in musical appreciation so that the 
pupils may be made familiar with the classics. 
In Cleveland, Ohio, for example, thirty mem- 
bers of the Symphony orchestra and each one 
of these thirty a master on his instrument- 
give instruction to school children, the cost of 
these lessons being paid out of the Community 
Chest. 

In practically every city where a symphony 
orchestra is maintained, special concerts are 
given for children of school age, and although 
only music of high standard is played, the 
difficulty is to find accommodation for all who 
want to attend. In New York, Walter Dam- 
rosch, who for years has given such concerts, 
was obliged last fall to 
transfer them from 
Aeolian Hall to Car- 
negie Hall of far larger 
capacity. Philadelphia, 
Cincinnati, Detroit, 
Chicago, Minneapolis, 
and San Francisco, are 
a few among the other 
cities where the attend- 
ance at such concerts is 
limited only by the 
seating capacity of the 
auditorium. 

America leads all the 
other countries in its 
patronage of music. 
This is why every con- 
cert artist who can pay 
his way across the 
Atlantic comes here 
with the hope of mak- 
ing a living. 

Nor are these artists 
heard only in the 
cities. Towns of no 
more than a few 
thousand population 
engage, year after 
year, some of the best 
talent that good music 
may be heard rightly presented. And when 
these people cannot hear an artist in their 
own town they journey at much expense to 
some near-by city to enjoy this privilege when 
the opportunity to do so presents itself. 

The sum total of the money thus spent each 
year for good music in the United States is 
estimated by some authorities in the billions. 



The Listeners' Point of View 



123 



Be that as it may, the amount is quite sufficient 
to prove to every broadcast director that there 
is a large public that wants the best music 
and nothing but the best over the radio. By 
this is not meant only the old classics, but also 
the lighter works with which good musical 
literature abounds. 

On the other hand, enormous sums are yearly 
spent to hear the so-called popular music, some 
of which is very good of its kind and has 
its legitimate use as a means of entertain- 
ment. Still larger sums are spent to hear 
out-and-out trash. These two sums total far 
more than that spent to hear music of high 
standard. 

But this does not necessarily mean that this 
sort of music should dominate the radio. 

Upon every broadcast director rests the 
responsibility of using for a constructive pur- 
pose this greatest musical opportunity that 
has ever been available to the public. These 
directors have no doubt had many unaccus- 
tomed problems to solve, and these difficulties 
must be taken into consideration when judging 
their programs. But they will never rightly 
solve the problem of radio music by appealing 
to the public to find out what is wanted. The 
majority of those who want good music will not 
trouble to express their desire. They will 
simply cease listening to the musical programs. 
Many of them have already done so because 
they think that very often the average musical 
program broadcasted is of a kind, both as 
regards the quality of the music and of the 
performers, that no one of discriminating taste 
can tolerate. 

There must also be an elimination as to 
quantity, for there are not enough singers or 
players capable of giving public performances 
to justify even half the number of musical 
programs now sent out through the air. But 
that is another story. 

The "Radio Trio" and Old Time Songs 

FOLLOWING the comment made in this 
department last month regarding the 
grateful custom of some broadcast sta- 
tions in featuring programs of old fashioned 
songs, comes the information that the first con- 
cert of this kind heard by radio was broadcast 
from station KDKA, Pittsburgh, the singers 
being Clara Huhn, soprano, Mabel King, con- 
tralto, and Roy Strayer, tenor. 
These singers have been so in demand by 




Campbell Studios, New York 
W1LLEM MENGELBERG 

For many weeks thousands of radio listeners heard the 
New York Philharmonic Orchestra every Wednesday 
evening give a program under the baton of the great 
Dutch conductor, Willem Mengelberg. With the closing 
of the Philharmonic's season came the end of what was 
one of the most remarkable musical opportunities ever 
afforded the radio public. The programs were broadcast 
from station WEAF 

radio audiences that they are now known as, 
"The Radio Trio." But singing before the 
microphone is only an incident in their musical 
lives as they are all professionals occupying 
important choir positions and also filling out of 
town concert engagements. 

Anne Griffiths, in whose studio these singers 
have received practically their entire training, 
is known throughout the Pittsburgh district 
as a musician of the highest ideals yet ever 
ready to seek new paths provided they give 
promise of leading to an artistic goal. This is 
why she was one of the first teachers of promi- 
nence in the country to encourage her artist 
pupils to broadcast. In response to the in- 
quiry, " But don't they have to cheapen their 
work in order to be popular?" her reply was: 

"Never! And let me add that the singer 
who must cheapen his or her art in order to 
please should not sing at all." 

The popularity of this trio, as evidenced 
from the large number of letters received 
whenever they have broadcast, is indisputable 
proof that if you do a good thing well enough 
it will please both the connoisseur and the 
layman. 



124 



Radio Broadcast 



Roy Strayer, tenor 





Mabel King, contralto 




Clara Huhn, soprano 
THE RADIO TRIO OF PITTSBURGH 



,n-tr I ' !''!. 



Music Students before the Microphone 

RETURNING to the subject of programs- 
commendation is due those broadcast 
directors who now and then present con- 
certs given by the students of some well known 
school of music. Such programs offer a 
valuable opportunity to other music students 
in that they make possible a comparison of 
achievement that is often worth more than the 
stereotyped lesson. 

A case in point was the concert given a short 
time ago by students at the Sherwood Music 
School of Chicago and broadcast through 
station KYW. It was an ambitious program 
consisting of numbers universally studied by 
advanced pupils, and in its execution was 
sufficiently good to be enjoyable apart from its 
special interest. Those students in other 
localities who heard it had a good chance to 
judge of the standard of instruction given in 
one of the largest music centers in the world. 

And speaking of Chicago, since the Tribune 
of that city has taken over the Zenith station 
(now WON), that station is fairly eating the 
air. And its musical programs are improving. 
The other night, just as this station was tuned- 
in, there came the surprise of hearing the 
opening phrases of what was immediately 
recognized as Debussy's "The Maid with the 
Flaxen Hair." To be sure, the piano tone did 



not have the desired warmth, but for all that 
it was a joy to hear this charming number. 
The pianist proved to be Miss Caroline John- 
son. Congratulations, Miss Johnson, for giv- 
ing radio listeners a chance to hear this in- 
gratiating number by the French composer who 
was the first great musical impressionist! 

Debussy leads us to comment on the pro- 
grams received from the Compagnie Fran^aise 
de Radiophone, of Paris. They recently fea- 
tured a concert called, "Festival Erik Satie." 
What it must have sounded like via radio it is 
impossible to imagine. For Erik Satie is a 
leader among those Moderns who cast aside all 
musical rules and go their own wild and erratic 
way when they compose. Key signatures, the 
division of the music into bars, time signatures, 
these and all other rules mean nothing to him. 
And as for harmony, he evolves his own. Yet 
fundamentally Satie is a sound musician. But 
to hear him by radio would very likely cause 
more amazement than pleasure. 

These French programs contain, in addition 
to works by native composers, others by the 
masters of German and Russian music. But, 
in the dozen or more programs at hand at this 
writing, America is represented only by, " Yes, 
We Have No Bananas," "Mr. Gallagher and 
Mr. Shean," "I Am Just a Little Blue," "1 
Want my Mammy," " Perfect Day," and 
"Swet Henry." Is "Swet" a misprint, or is 



The Listeners' Point of View 



there a fox trot with such a title? One 
should never be ashamed to confess ignor- 
ance where knowledge should be bliss hence 
this inquiry. 

These numbers, compared with the re- 
mainder of the programs on which they appear, 
show all too clearly what the French think of 
American music. 

The Funereal Star Spangled Banner 

WHY broadcast "The Star Spangled 
Banner" at a tempo that makes it 
sound like a funeral hymn? Twice 
in one evening it came through the air at such 
a mournful pace one imagined that every flag 
in the country would be lowered at half mast 
in the belief that some terrible catastrophe had 
overtaken the nation. 

In the name of all that is patriotic, speed it 
up, you who broadcast 
this national song! 

EVERY announcer 
in the country 
might well follow the 
example set by the man 
at station WHAA, Iowa 
City, who spells the 
names of those heard 
during the program. We 
all know how difficult it 
is to understand per- 
fectly a proper name 
the first time we hear 
it. Although speech 
sounds clearer over the 
radio when you have 
the right kind of a re- 
ceiving set properly 
adjusted than it does 
otherwise, yet one 
cannot always be cer- 
tain that the name is 
correctly heard. So we 
herewith present our 
thanks to that WHAA 

announcer who first speaks a name and then 
spells it. There was the case of the program 
of old hymns given at this station recently. 
They were sung with a simplicity so free from 
sentimentality that they sounded almost like 
folk songs. And the announcer made it per- 
fectly clear that the singer's name was Jeanne 
Wolfe. 




WLAG, the Twin City station, Minneapolis, 
has a woman announcer (and, indeed, execut- 
ivedirector) Miss Eleanor Poehler who is the 
equal of any man announcer in the country and 
the superior of some. 

And it was something of a surprise to hear 
recently a woman's voice announcing the num- 
ber of an afternoon program broadcast from 
Ohio State University, Columbus. 

After all, why not? Women have success- 
fully competed with men in nearly every 
branch of work. Why shouldn't they be not 
only announcers but also broadcast direc- 
tors? Why shouldn't every large broadcast 
station have both a man and a woman director? 
Such an arrangement would contribute toward 
giving the programs a wider appeal. Men 
know some things about how to get satisfactory 
contacts with the public that women do not 
know; and by the same token, women know 
some things regarding 
this same matter that 
men have never learned 
and probably neverwill. 
This suggestion is 
offered to broadcast 
directors for contem- 
plation, if indeed they 
ever have a chance in 
these hectic radio days 
to do any quiet de- 
tached thinking. 

And Now Programs 
in Spanish 



I 



Nicholas Hay 



WILLY POGANY 

You could never guess his occupation from this picture, 
so we will enlighten you by explaining that he is a cele- 
brated illustrator and decorator. He was born in 
Hungary, studied in Paris, spent ten years in London, and 
now lives in this country. He has illustrated more than 
one hundred books and decorated many famous buildings. 
He gave a broadcast talk at station WOR not long ago 



T WILL soon be 
quite the vogue to 
broadcast special 
programs given entirely 
in Spanish for the 
benefit of the Latin- 
American countries. 
The first complete pro- 
gram of this character 
was given at station 
KDKA by Mrs. Leora 
during her studies 
Spanish music, and 



Sage McKennan who 
abroad, specialized in 
by Victor Saudek and his Little Symphony 
orchestra. Mrs. McKennan sang a group of 
traditional Pyrenese songs and the orchestra 
numbers were either by Spanish composers 
or works based on Spanish themes but written 
by composers of other nations. The an- 



126 



Radio Broadcast 



nouncer on this occasion was D. Santini, of 
Santa Fe, Argentina. 

Then, a few days later, station WGR at 
Buffalo gave a Spanish program in which all 
the performers, with the exception of the piano 
accompanist, were Spaniards. It was not 
necessary that the accompanist be of this 
nationality as the piano 
can speak in all langu- 
ages with equal facility. 

And now it's up to 
someone to write a 
song about, "Hands 
Across the Air." 

Dramatic Celebrities 
Alone 

STATION WOR, 
L. Bamberger & 
Co., Newark, has 
been carrying a fine fea- 
ture in the presentation 
of many dramatic cele- 
brities in short talks or 
readings. This series, 
which has also included 
celebrities in other lines 
of endeavor, has been 
received with such en- 
thusiasm as to prove 
beyond all doubt that 
people want something 
more than ephemeral 
entertainment over the 
radio. These talks 
have been instructive. 
And it seems the only 
desirable way for 
dramatic artists to 
broadcast. 

It may be that the giving of plays by radio 
will sometime prove a practical method of 
producing drama, but at present, to some of us, 
it presents difficulties that make for dissatis- 
faction. WGY at Schenectady put on the 
comedy "Snowball," about a month ago, and 
although it came through clear, with every 
accent in speech plainly brought out, it all 
seemed fragmentary and confused. Like grand 
opera, drama appeals to more than the sense of 
hearing. It seems as if it were over-straining 
the resources of the radio to expect effective 
results when either opera or drama is broadcast. 
But perhaps time will bring out developments 



along these lines that will astonish us. Indeed, 
nothing is impossible of execution of which the 
human mind can conceive. 




WHEN station WOAW at Omaha cele- 
brated its first anniversary in April, a 
portion of the program was given by members 
of the Chicago Bush 
Conservatory of Music 
faculty. The concert 
proved one of the best 
musical features heard 
via radio in many a 
day, and made some 
of those who listened 
to it lament that pro- 
grams of this kind are 
not broadcast fre- 
quently. 



T 



ANNE GRIFFITHS 

Whose achievements as voice teacher and coach in in- 
terpretation have done much to raise the standard of 
singing in Pittsburgh and vicinity. Miss Griffiths is a 
firm champion of the radio, and equally firm in her belief 
that it should be used to elevate musical taste rather 
than simply to entertain 



HE monthly re- 
cital given by the 
Euterpean Club of Fort 
Worth through station 
WBAP is well worth 
listening to, not only 
because of the excellent 
performances given but 
also because they afford 
opportunity to realize 
the local talent avail- 
able in that progressive 
Southern city. But for 
that matter, all who 
are closely in touch with 
musical development 
in this country know 
that Texas is ever 
abreast of the times 
in this respect. There 
is not a concert artist 
before the public to-day who does not jump at 
the chance to get Texas engagements. And it 
is also a field that yields golden harvests to 
grand opera companies. 



COMMENT made in this department 
last month on the inspiring effect of hear- 
ing by radio the choir of St. Paul's Cathedral 
at Detroit, has brought the information that 
the organist and musical director of the 
cathedral is the widely known musician, 
Francis A. Mackay. It is again a pleasure to 
speak of the vitally artistic quality of the 
choir's singing under his guidance. 




DON WALLACE 

An amateur radio operator of Minneapolis at his station 9 ZT. He was recently awarded the prize 
cup offered annually by Secretary of Commerce Hoover for the best amateur radio station in the country 



The March of Radio 

Hoover on Broadcasting Control 



T 



HE furor started by the "monopoly 
control" cries of station WHN when 
the A. T. & T. suit against it was 
started naturally would call for some 
statement from those government of- 
ficials responsible for issuing radio station li- 
censes. Perusal of the license law may not 
at once disclose clauses under which the Secre- 
tary of Commerce could act, to revoke licenses 
"for cause," but judging by the way in which 
Congress can act when it thinks of losing the 
soldier vote, it would not take more than a day 
or two to enact any law which the radio public 
might demand, provided their demands were 
backed by as powerful an organization as the 
American Legion. 

Evidently feeling that the action of the A. 



T. & T. Company in starting suit to close un- 
licensed stations called for some action on his 
part Secretary Hoover made public the follow- 
ing statement: 

I am in receipt of many requests for my views as to 
issues now before the Courts bearing on the control 
of radio broadcasting. While it is impossible for 
me to express any opinion on particular issues that 
are before the Courts or the Federal Trade Com- 
mission, I can state emphatically that it would be 
most unfortunate for the people of this country to 
whom broadcasting has become an important inci- 
dent of life if its control should come into the hands 
of any single corporation, individual, or combination. 
It would be in principle the same as though the entire 
press of the country were so controlled. The effect 
would be identical whether this control arose under 
a patent monopoly or under any form of combina- 



128 



Radio Broadcast 




RUNNING ASHORE ON A COAST LIKE THIS 

Is not to be relished, and it would happen more frequently were it not for the radio signals 
which supplement the warning flashes from the ever-vigilant outposts of our lighthouse service 



tion, and from the standpoint of the people's interest 
the question of whether or not the broadcasting is 
for profit is immaterial. In the licensing system put 
in force by this Department, the life of broadcasting 
licenses is limited to three months so that no vested 
right can be obtained either in a wavelength or a 
license. I believe it is safe to say irrespective of 
claims under patent rights on apparatus that broad- 
casting will not cease and neither will our public 
policy allow it to become monopolized. 

We heartily agree with the general sentiment 
of this statement. It is an excellent thing for 
United States radio that the department which 
grants broadcast licenses is supervised by such 
a secretary. We are not at all sure that the 
statement, "from the standpoint of the peo- 
ple's interest the question of whether or not the 
broadcasting is for profit is immaterial," is to be 
taken at its face value. Probably Mr. Hoover 
has not thought this thing through. We are 
not convinced that in this sentence the whole 
question as to how radio is to develop does not 
rest. " Radio for profit," the Secretary's state- 
ment notwithstanding, does not sound as though 
it promised much for the listener. 

London Has Hard Work Getting Through 
to U. S. 

WE HAVE yet to learn much about 
radio transmission. In the most 
recent attempt to bridge the At- 
lantic westward there were nine stations opera- 



ting, all connected by wire to radiate the same 
program. Each of the stations was on a dif- 
ferent wavelength. The power any one lis- 
tener in America could pick up was that from 
one station only. 

Although some elaborate preparations had 
been made to receive this transmission, very 
meager results were obtained. The RADIO 
BROADCAST super-heterodyne seems to have 
done as welf as, if not better than, any other, 
but even this was successful in picking up music 
only; Marconi's message of greeting was ap- 
parently cast into a barren waste in so far as 
America was concerned. 

It is Marconi's idea that this trans-oceanic 
transmission should be carried out by his ray 
radio, and we thoroughly agree with him. 
Could "mirror" stations be put up on both 
sides of the Atlantic there is no doubt that 
transmission would be altogether successful. 
What information we have on the method 
shows that if suitable mirrors were used at both 
transmitting and receiving stations the signal 
strength would be increased at least two hun- 
dred times. 

When we think of KDKA's consistently suc- 
cessful 94 meter channel and WGY's recent 
transmission on 104 meters across the Atlantic 
it seems strange that the waves traveling in 
the opposite direction should encounter so for- 
midable a barrier. We may discover why 
some day. 



The March of Radio 



129 



Squealing Sets to Go Surely 

THERE is now no doubt that the single 
circuit regenerative receiver, against 
which RADIO BROADCAST has consis- 
tently waged war, is doomed to go. The dis- 
satisfaction of the listening public has at last 
penetrated high places, and we now hear Mr. 
Sarnoff of the Radio Corporation tell a Congres- 
sional Committee that "the Radio Corpora- 
tion recognized the problem of radiation and 
favored a law prohibiting the sale of receivers 
which produced audible interference with 
others in close proximity." Within a period 
of two years he would make it unlawful for 
any one to use a radiating receiver! 

It is with great satisfaction that we see this 
company, many of whose sets constitute one of 
the greatest causes of inter- 
ference, finally change its 
attitude on this question. It 
is, it seems likely, more satis- 
factory to us to think of this 
law prohibiting radiating re- 
ceivers than it is to those 
hundreds of thousands who 
paid high prices to the 
Radio Corporation for the 
single circuit regenerative 
receivers which it so ardently 
advocated a short time 
back. It seems as though 
Mr. Sarnoff ought, in all fair- 
ness, to offer some sort of a 
reasonable "swap" with the 
former customers to whom 
he sold these sets, now con- 
demned byhim. It is hardly 
fair to sell a man something 
and then agitate for a law 
to make it illegal for him 
to use the apparatus. 



Praiseworthy Broadcast 
Engineering 

A A recent dinner of 
the alumni of Mas- 
sachusetts Institute 
of Technology, a feat of 
broadcasting was success- 
fully accomplished. There 
was a notable list of 
speakers. The pick-up in 
the banquet hall operated 



WJZ. From this operated WGY. KDKA in- 
tercepted WGY's transmission and started the 
program out again on two waves, one for its lis- 
teners and one to actuate its KFKX Hastings 
station as well as station 2 AC in Manchester, 
England. Hastings further relayed the pro- 
gram to KGO in San Francisco, which then 
threw it out over the West Coast and the 
Pacific Ocean. 

As a result of this network control, cable- 
grams were received during the progress of 
the banquet so "General Harbord, President 
of the Radio Corporation, was able to say 
that the speakers had been heard from 
Melbourne to Constantinople. Real broad- 
casting, which completely covers the civil- 
ized parts of the globe, is evidently not far 
distant. 




THE OLD AND THE NEW 

The towers of the United States Naval radio station NPP at Peking 
show in decided contrast to the good old Chinese roof in the background 



130 



Radio Broadcast 



Outlaw Stations to be Closed 

x" X UITE some time ago we were talking 
I 1 to an engineer of the American Tele- 

V>/ phone and Telegraph Company 
^^" "about the development of radio and 
the part his Company was playing in this de- 
velopment. At that time the Radio Corpora- 
tion had been formed, and, as is now common 
knowledge, the Telephone Company had been 
given a virtual monopoly in selling transmitting 
equipment for broadcasting purposes. To 
offset this concession, the Telephone Com- 
pany agreed to keep out of the radio re- 
ceiver business. As a result of this agreement 
we have seen no A. T. & T. radio receivers on 
the market, although their well known am- 
plifier unit to operate a loud speaker, convinces 
us that the Company certainly could design 
and build very excellent radio receivers. The 




Navana. London 

HUGH S. POCOCK 

Editor of the Wireless World and Radio Review of London. Mr. Pocock, 
in cooperation with the engineers of the British Broadcasting Company, 
had much to do with the success of the transatlantic broadcasting tests 
conducted last November by his magazine, the "B. B.C." and RADIO 

BROADCAST 



amplifier is evidently not construed in the Cor- 
poration agreement as " radio receiving equip- 
ment." 

It seemed at once evident that the other 
members of the Corporation "put it over" on 
the A. T. & T. signatories. Greater profits 
are possible in the sale of millions of receivers 
which are used compared with those arising 
from the very few transmitting stations re- 
quired to cover the country. Matters which 
seem so obvious are frequently not. Perhaps 
those responsible for the policies of the A. T, 
& T. Company looked farther than the im- 
mediately visible dollar of profit. 

There is no doubt about the tremendous 
profits to be had from the sale of radio receivers 
by merely glancing over the advertisements 
in any paper it is easy to see that any of the 
standard sets could be materially reduced in 
price and still leave a handsome profit for the 
manufacturer. In fact we predict 
this very thing will come about in 
the next few months. But of all the 
millions of receivers which the Amer- 
ican people have bought and which 
have yielded many million dollars 
of profit to the Radio Corporation 
(other than the A. T. & T.) depend 
upon transmitting stations for their 
utility, and all the transmitting sta- 
tions, according to the agreement, 
are to be furnished, and to a certain 
extent controlled by the Telephone 
Company. 

There is apparently at least one 
objectionable clause in the contract 
which the purchaser of the transmit- 
ting set has to sign which compels 
the purchaser to agree not to use 
the station for profit, as WEAF, the 
Telephone Company's own station 
is continually doing. For sending 
out the concert of The Happiness 
Boys or Chicklet Trio and whatnot, 
some firm is paying the Telephone 
Company about $400.00 an hour. 
Naturally the managers of other sta- 
tions would like to use theirs for a 
few hours each week in this fashion, 
but according to the contract they 
can't. There may be other condi- 
tions imposed upon the purchaser 
which seem to him unwarranted, 
but we hear more about this one 
than any other. 



The March of Radio 



The reader is very likely to conclude that in 
this matter the Telephone Company is monopo- 
listically culpable, that it intends to keep a tight 
hand on any possible profit which may accrue 
from regular broadcasting. But the answer 
of our engineer friend to whom the question 
was put, shows that the gain of profit is at 
least not the only motive controlling the moves 
of the Telephone Company, if in fact it is the 
prime motive. Perhaps they feel that more 
profits may possibly be derived in an indirect 
rather than in a direct way. "The Telephone 
Company," said the engineer, "sees that radio 
broadcasting is very likely to develop into one 
of the most vital communication schemes of the 
age" and his company is a communication 
company. The proper and reasonable develop- 
ment of the art, rather than any immediate 
profit, he thought, would be the force which 
decided the company's course. 

He told of a case of a New York church ask- 
ing for a broadcast set the minister was badly 
infected with the "fundamentalist" germ 
and itched to spread his Sunday sermons 
beyond the walls of his edifice. Now to 
spread the teachings of Christ is surely the 
most noble task to which broadcasting can be 
put, but it is not at all evident that such would 
be the use of this set. So many preachers to- 
day insist on their version of what Christ 
taught. Views on the subject are so diversified 
that many times they seem almost opposed to 
one another. If this minister were allowed to 
broadcast, how about his "modernist" brother 
who professes Christianity as ardently? Shall 
he be refused a transmitting set, or shall the 
Telephone Company give him a set also and 
let the Sunday air be filled with conflicting ideas 
of Darwin and Bryan? And the conflict 
would be as bad in subject matter as in wave- 
length, since probably both would have to 
transmit at the same frequency. 

Foreseeing this imminent battle of the ether 
if it sold a broadcasting set to any who apply, 
the A. T. & T. Company refused to sell a set to 
this church with what result? The church 
is now operating a "bootleg set!" Dispensing 
the gospel over a channel which is operated 
against the laws of the United States for 
the Government regulation, giving protection 
to a patentee, is as much a part of our Con- 
stitutional law as is that granting "life, liberty, 
and the pursuit of happiness." There are 
undoubtedly many broadcasting stations oper- 
ating to-dav in violation of law, for no matter 




WILLIAM GIBBS McADOO 

Addressing the radio audience before a Los Angeles 

microphone. Mr. McAdoo is another candidate for 

the Presidency who says he intends to use radio in the 

campaign 

what arrangement of apparatus is used, all of 
them must use an oscillating triode as their source 
of power. The patent covering the use of oscil- 
lating tubes is owned by the Radio Corporation. 

What then is to be done to these stations 
which are operating in defiance of the patent 
law? Are they to be left alone, or shall the 
patent law be enforced? The A. T. & T. 
Company proceeding legally against infringers, 
requested the Court to compel one of these 
outlaw stations, WHN, to cease operation or 
comply with the agreements under which the 
Telephone Company permits the use of its 
patents. This WHN settled out of court, ac- 
knowledging the validity of the patents and 
signing a license agreement. 

This suit has started much loose talk about 
"freedom of the ether," "monopoly of broad- 
casting," but the public should not be misled 
by any such statements. The question at 
issue is a very simple one. Is the owner of a 
patent entitled to legal protection? If it ap- 
pears that this question of broadcasting is so 
revolutionary in its service and requirements 
that the present patent law can be enforced 
only at the expense of the interests of the people 
then undoubtedly our patent law requires re- 
vision. But until that revision is enacted into 
law we can see no other solution to the broad- 
casting problem than compliance with the 
agreements the Telephone Company sees fit 
to incorporate in its licenses. 



132 



Radio Broadcast 




Courtesy If'ireless World and Radio Review 
AN ELABORATE BRITISH AMATEUR RECEIVER 

Which is fairly characteristic of pres- 
ent day English amateur construction 

It is probably fortunate for the broadcast 
listener that this question is at present in the 
hands of the A. T. & T. Company. This gi- 
gantic corporation with its hundreds of thous- 
ands of stockholders is subject to all kinds 
of governmental inquiry because of its inter- 
state character. And if there is anything this 
corporation does not want to start it is a popu- 
lar demand for government ownership of the 
American telephone system. Such a move- 
ment might gain considerable momentum under 
guidance of the radicals of North Dakota, for 
example, if it could be reinforced by the talk of 
"controlling the religious, educational, enter- 
tainment, and political destinies of the nation" 
which the management of station WHN as- 
serted to be the aim of the Telephone Company. 

We feel that some revision of the patent law 
is probably required; as it stands the people of 
the country give the patentee the opportunity 
to fleece them as much as he desires. If it is 
a cure for tuberculosis that the inventor dis- 
covers, he could legally collect hundreds of 
millions of dollars from the sufferers. Perhaps 
a patent on a device or idea which fills a great 
public need should have such extra governmen- 
tal control exercised to insure to the people 
(who themselves grant the patent) of its rea- 



sonable use. But the fact that WHN, by 
signing the agreement with the A. T. & T. 
Company, is not allowed to do advertising for 
money, cannot well be classed as an oppressive 
measure, as the manager of WHN seems to re- 
gard it. We think that the interests of the 
radio public are being conserved when such 
stations are prohibited from broadcasting for 
direct monetary profit. Direct advertising by 
radio is highly questionable even when tried by 
so excellent a station as WEAF. 

A Municipal Broadcasting Station for 
New York City 

VOLUMINOUS correspondence from 
Commissioner Grover A. Whalen of 
New York, has arrived. He mourns the 
difficulties he has had in trying to establish a 
municipal broadcasting station for his city. 
As he is apparently entirely dissatisfied with the 
manner in which the Western Electric Com- 
pany is willing to sell and install its broad- 
casting apparatus, he has written at length 
on the subject, asking the Federal Trade Com- 
mission to investigate the "monopoly of the 
air" which he asserts the A. T. & T. Co. is 
maintaining. He explains the reasons for his 
actions in this matter in the last sentence of 
his letter to the Board of Aldermen " I believe 
that the people of the City of New York, with 
its millions of radio fans, should be acquainted 
with the commercial aims and monopolistic 
tendencies of this Company to coerce the City 
which is endeavoring by means of the estab- 
lishment of this broadcasting station to give 
maximum service and greater happiness to its 
citizens." 

At the request of the city, the A. T. & T. 
engineers had estimated the cost of this sta- 
tion. It was due to their preliminary tests that 
the location proposed by the city (on the top 
of the Municipal Building) was found to be a 
very unsatisfactory one, and that another, 
much more efficient electrically, was found. 
This new location, however, seemed to be very 
poor, from the city's standpoint, because it 
required a wire connection with the City Hall 
and these wires would be owned by the Tele- 
phone Company. Altogether it seems to the 
Commissioner that this company is maliciously 
hindering the city's radio venture so he loudly 
calls for Federal vengeance. 

The real facts of the case are not all brought 
out in the Commissioner's correspondence, but 



The March of Radio 



33 



he has apparently disturbed the Radio Cor- 
poration officials sufficiently to have them in- 
struct the Westinghouse Co. to offer a broad- 
casting set to the city. Mr. Whalen is rejoiced 
that now he may broadcast without objection- 
able controlling agreements. Just how the 
city is going to use the set after it is obtained 
is not clear, neither is it apparent, we desire 
to point out to the Commissioner, that the 
stuff which is likely to be sent out from his sta- 
tion will "give greater happiness to the citi- 
zens" as he fondly hopes. If he would take 
the trouble to inquire, he would find out that 
most of his "million fans" are pretty well satis- 
fied with the programs the other stations of the 
Metropolitan area have been furnishing them 
for the last year. He will have to extend him- 
self a good deal to make the average citizen feel 
that the municipal station is not a 
nuisance, if it interferes in any 
way with these other stations. 

The tone of the city administra- 
tion's criticism of WEAF's mana- 
gers is well shown by the stand 
taken on the acquirement by this 
station of permission to carry on 
experimental work of development 
during the hours from 2 A. M. to 2 
p. M. In getting from Secretary 
Hoover this special Class D station 
privilege, he "finds this doministic 
(whatever that word may mean) 
company securing the one remain- 
ing concession that was needed in 
order to completely dominate and 
control the air. This appeared in 
the form of an order from the 
Secretary of Commerce notifying 
broadcasters that after this date 
there would be in existence Class 
D. or Broadcast Improvement 
Class, stations. So evidently this 
"doministic" company has hood- 
winked Secretary Hoover and he 
too, is "agin the city." 

Annual Report of the Radio 
Corporation 

THE immense growth in the 
country's radio is indicated 
by the report of the Radio 
Corporation for the year just past. 
From a gross income of about 
$15,000,000 in 1922, the busi- 



ness of the company increased to more than 
$26,000,000 in 1923. .The net income of 
the Corporation has grown in a manner 
which should be very satisfying to the 
stockholders. It was $426,799 in 1921, 
$2,974,579 in 1922, and $4,737,774 in 1923. 
Practically all of the increase in business re- 
sulted from the sale of receiving sets, many 
of them now to be outlawed, thus making way 
for others. Of the net income of the company 
only 9.5 per cent, increase occurred in trans- 
oceanic telegraphy -and 17 per cent, in the 
marine traffic of the company. 

Current assets of the corporation exceed the 
liabilities by more than eight million dollars and 
the 7 per cent, dividend on: the preferred stock 
has been made cumulative. Two additional 
radio channels have been put intooperation dur- 




MUNIC1PAL BUILDING 

New York, where the City of New York is soon to install a 1000 
watt broadcasting station. The old City Hall in the foreground 



134 



Radio Broadcast 



ing the past year, one to I taly and one to Poland . 
New circuits to South America are planned, 
in addition to which there are at present nine 
channels in service, to Great Britain, Norway, 
Germany, France, Italy, Poland, Hawaii, and 
Japan. 

The report concludes with the statement 
that the company's engineers are devoting 
themselves to the solution of the broadcasting 
situation "with the ambition of perfecting the 
service to the satisfaction and benefit of the 
American people." 

Armstrong to the Front Again 

ON MORE than one occasion the radio 
receiver has received tremendous im- 
petus from the contributions of E. 
H. Armstrong, the patentee of regeneration, 
super-regeneration, and the super-heterodyne. 
Now he has designed a new set which the Radio 
Corporation is selling under the name of the 
Regenoflex. 

Seldom has it occurred in any field that one 
experimenter has contributed so richly. The 
regenerative receiver, with its ultra-sensitivity 
in the hands of a skilled operator, did more than 
any one other thing in the decade 1910-1920 to 
advance the art of radio communication. By 



it European signals were consistently copied 
in the laboratory at Columbia University, 
using one triode. Ten years ago in the same 
laboratory it was generally possible to hear 
the West Coast stations talking to Honolulu 
(by code, of course) and to copy these messages 
when the stations themselves were continually 
calling for repeats. 

His next contribution, the super-heterodyne, 
makes possible a most remarkable receiving 
set. This principle offers apparently the best 
method of getting high amplification of weak 
radio signals, and we have always recommended 
it as the best receiver, for those who could af- 
ford it. Its control is fairly simple, it is non- 
radiating, and it can be made to bring in the 
most distant stations, apparently still desirable 
to many broadcast listeners. 

For his super-regenerator we cannot say so 
much. When properly built and adjusted this 
set produces a lot of noise, but that apparently 
is about what it is good for. As usually em- 
ployed this super-regenerator amplifying ar- 
rangement gives very poor quality reproduction. 
Quality, is the one feature which the radio re- 
ceiver manufacturer must strive for more and 
more. Radio transmission, per se, permits of 
almost perfect reproduction of voice and mu- 
sic, whatever distortion occurs is due to the 




AT WHN 

Billy West and Billy Murray broadcasting. VVEAF's suit against this station for alleged violation 
of American Telegraph and Telephone vacuum tube patents was recently adjusted out of court 



The March of Radio 



35 




A MODERN ONE-MAN GERMAN BAND 

Has been evolved by this rather ingenious German who has mounted this radio set on a cart, which may have before held 
his hand organ. He tunes in Berlin programs and depends on the financial appreciation of his audiences for support 



imperfect electrical apparatus employed at 
the transmitting and receiving stations and 
the super-regenerator did not contribute much 
to the solution of this problem. 

He has lately been endeavoring to make the 
operation of the super-heterodyne more simple 
and has apparently succeeded at the same 
time lessening the number of tubes required 
from eight to six. He is of the opinion that 
his latest arrangement, in which regeneration 
and reflexing are employed, as well as the 
double detection idea, gives as good results (in 
so far as amplification is concerned) with its 
six tubes as is obtained with the ordinary cir- 
cuit using eight tubes. The internal capacity 
of the triodes, between the grid and plate, is 
partly compensated as is done in the Hazeltine 
neutrodyne sets. 



To make the adjustment of the local oscilla- 
tor more independent of the loop antenna tun- 
ing, a "second harmonic" oscillator is used; 
the oscillator, instead of generating a fre- 
quency nearly the same as the incoming fre- 
quency, generates about one half this fre- 
quency and the intermediate frequency, for 
the intermediate frequency amplifier, is ob- 
tained by the beat note between the signal 
frequency and the second harmonic of the 
local oscillator. 

The engineers of the Radio Corporation have 
done an excellent piece of design and construc- 
tion on the new set, and if it is anywhere near as 
good in performance as the inventor claims for 
it, the Regenoflex should prove to be a popular 
receiver provided the price is kept as low as 
the amount of material used in the set justifies. 

J. H. M. 



Pity the Poor Broadcaster 

An Intimate Confession, Wrung from One of Them 



By CARL DREHER 

Drawings by F. F. STRATFORD 



HOW fortunate you are to be in such 
an interesting business as broad- 
casting!" A professional broad- 
caster is doubtfully blessed by 
being forced to hear this remark, or 
something very similar, at least twice a day. 

Well, it is not the worst business in the world, 
by any means. At the same time it has its 
drawbacks. Being in a gloomy mood, I pur- 
pose to enumerate a few of them. 

The wonder and mystery of broadcasting 
have been so much cried abroad in the land that 
many people expect miracles of the poor broad- 
casters. For example, the matter of the plac- 
ing of microphones. Everybody wants to be 
broadcast, but the microphones must not be 
visible, oh dear no. Hide them in the foot- 
lights, or hang them as high as Haman in the 
proscenium arch, or keep them warm behind 
the boilers in the engine room, but don't let 
any of the soloists, or speakers, or even the 
audience, suspect that there is a microphone 
in the house. If they do, all is lost, including 
honor. "What," I can hear them say, "the 
microphones have to be placed in certain de- 
finite places?" A long argument usually 
ensues, the broadcasting station's representa- 
tive explaining that a microphone picks up 
only what comes to it in the form of sound 
energy, and that the operators, far from being 
able to make it behave otherwise, are different 
from other people only in knowing what the 
microphone will do and what it will not do. 
Thus, if it is placed on the floor under the 
piano, the piano will sound on the air like the 
merry bouncing of ash cans on urban side- 
walks, and the rest of the show will be conspicu- 
ous by its absence, and the station will receive 
fifty-six hundred threatening letters the next 
morning from irate listeners, including the 
friends and families of the performers. Finally 
an agreement is almost always reached, for the 
representatives of the artists discover that the 
microphone is merely a round black object 
considerably smaller than a man's hand, on a 
slim stand, and that the broadcasters want to 



place it only about waist high, and not, as 
was feared, right in front of the prima donna's 
nose. But in some cases, when it develops 
that the microphone must be somewhere, and 
there is no way of making it invisible like the 
air, all bets are called off, and the radio audience 
has to listen to something else. 

IN THE STUDIO IT'S NOT SO BAD 

A..L this applies only to outside broad- 
casting. In the studio, of course, the 
operators have things more their own way. 
But even in the studio, in the matter of placing 
bands, for example, it is sometimes found that 
the musicians balk at the positions selected for 
them. We must then compromise so that a 
fairly good orchestral balance can be had on the 
air with the musicians lined up so that they 
can play together. Usually this is accom- 
plished by getting the different pieces to 
play with special loudness or softness, the 
music sounding better on the air, very likely, 
than in the studio. But it requires consider- 
able persistence and tact to explain this to 
people. 

Some performers are microphone-shy. This 
is often the result of exposure to a squawking 
loud-speaker overloaded to about ten times 
its proper capacity; hearing the result the 
listener resolves, rationally enough, never to 
let himself be broadcast. The worst of it is 
that the higher a man's musical competence, 
the more severe will the case of micro-phobia 
be, and the greater the loss to the broadcasting 
art during its duration. The broadcasters who 
try to do uniformly good work, and succeed 
almost all the time, have to carry the handicap 
of poor broadcasting by other stations, and 
incompetent amateur and professional re- 
ceiver demonstrations. The prejudices thus 
engendered injure the art as a whole, and the 
good stations suffer with the bad. Possibly 
it was after hearing the braying of some radio 
store's horn, trying to make enough noise to 
get over street traffic, that M. Clemenceau, 
on his recent visit to the United States, flung a 



Pity the Poor Broadcaster 



>37 



public address microphone to the floor on one 
occasion. It makes little difference whether or 
not the report is true. One can hardly blame 
his feeling. 

TRYING TO MOVE AN AMBASSADOR 

SOME listeners have an exaggerated idea 
of the power and influence of the techni- 
cal staff of a broadcasting station. Recently, 
while WJZ was broadcasting the retiring Brit- 
ish Ambassador, Sir Auckland Geddes, speak- 
ing at the Pilgrims' Society dinner from the 
Hotel Plaza in New York City, an irate lis- 
tener called up the station to complain that 
the ambassador was talking too slowly, and 
was there no way to speed him up? On being 
told that ambassadors were in the habit of 
talking as fast or as slowly as they pleased, he 
hung up with a loud "Bah!" and is no doubt 
now going around telling the populace what 
dubs those broadcast fellows are, that not one 
of them had the nerve to step up to Sir Auck- 
land and say " Hey, Ambassador, speed it up a 
little, wontcher?" 

Every broadcasting station of any size is 
bombarded with requests 
from people who want to 
be mentioned on the air. 
Usually they are holding a 
party in honor of someone, 
and they explain that it 
would be so nice to turn 
on the radio and hear it tell 
the world that this is Mr. 
Ignatz Verplatz's birthday, 
and that they are giving a 
party in honor of the same 
at his residence on Presi- 
dent Street, Brooklyn. 
This is, of course, a matter 
of intense public interest. 

WHY READ TELEGRAMS? 

THE larger stations, as 
a matter of fact, are 
discontinuing the practice 
of reading or acknowledg- 
ing telegrams via the air. 
This was perhaps justified 
in the early days of the 
art, when it was a subject 
for great amazement that a 
certain station had been 
heard in Oshkosh, 400 miles 
away; but now this is such 



an everyday occurrence that no further novelty 
or interest attaches to it. The stations are 
glad to get word from their listeners, of course, 
but the proper way to acknowledge them is by 
letter. The ether, it is becoming more and 
more evident, should be reserved for public en- 
tertainment. 

Occasionally people send in technical queries, 
accompanied by hook-ups, and want them 
answered on the air. Just how this is to be 
done is not clear; at least until radio television 
or telephotography^ becomes a reality; talking 
about wiring diagrams, without a pencil and 
paper handy, is too much like lecturing on the 
fourth dimension. It is bad practice, in 
general, to send technical inquiries to a broad- 
casting station. The broadcasting engineers 
and operators have to worry about keeping the 
station on the air, and meggering wire lines, 
and doctoring microphones, and maintaining 
good quality, and it is hardly fair to ask them 
to diagnose the ills of individual receiving sets, 
when there are several radio periodicals with 
facilities for this service and willingness to 
extend these facilities to their readers. 




"THEN THE PIANO SOUNDS LIKE THE MERRY 
BOUNCING OF ASHCANS ON URBAN SIDEWALKS" 



138 



Radio Broadcast 




SOME PERFORMERS ARE MICROPHONE-SHY 



from one or more of the local sta- 
tions are below the intensity of 
WGY at Schenectady or KDKA at 
Pittsburgh or W DAP at Chicago. 
It is hard to explain to people that 
this is an act of God, that the city 
was laid out or grew up naturally 
and more or less aimlessly, and cer- 
tainly without any thought of 
broadcasting, and that the combi- 
nation of man-made structures and 
the topography of the region, put 
together, make the transmission 
what it is in any particular locality. 

THE BROADCASTING STATION'. 
BLAME HEADQUARTERS 



Keeping advertising off the air is another 
extra responsibility in operating a non-toll 
broadcasting station. Most of the performers 
understand the necessity for this and cooperate 
in good faith. Occasionally an attempt is 
made to put something over. One instance 
is on record where a singer of popular song 
hits started working in the name of a dance hall. 
He was promptly taken off the air unknown to 
him, it is interesting to observe for the balance 
of the number. Constant vigilance, and the 
exercise of quick judgment, are prime necessi- 
ties in the operation of a broadcasting station. 

SIMON SAYS YES, BUT SIMEON NO 

A BROADCAST ING transmitter, like all 
mundane objects, has to be located some- 
where, but, judging by the complaints of some 
of its patrons, one would not take this to be the 
case. The listeners who happen to be close 
by complain of the intensity of the signals, and 
request that the power be cut to one fourth, 
to make it easier to tune out the signals. 
Listeners at more remote points want louder 
signals, and urge that the station be made 
four times as powerful. It is very hard to 
please everyone, and broadcasting is pre- 
eminently a business in which one must try to 
please everyone. This brings up the question 
of dead spots in urban broadcasting. Every 
city station has areas, sometimes quite close 
by, where its signal is weak. There is sure to 
be a constant deluge of complaints from listen- 
ers in these neighborhoods who want to know 
why the other station, with no more power, and 
perhaps farther away, is louder. There are 
neighborhoods in New York City where signals 



THE broadcasting interests, like other 
public utilities, are blamed for a great 
many things for which they are in no wise 
responsible, as well as for their actual short- 
comings. Besides dead spots, they are blamed 
for everything from high tension induction to 
static. When anything is wrong with the 
reception, most of the listeners can be trusted 
to be fairly discriminating and to put the re- 
sponsibility where it belongs, but a minority can 
be trusted equally to make a scapegoat of the 
broadcasting station. Of course the staff of 
a broadcasting station is composed of human 
beings; they are willing to be condemned for 
their sins of omission and commission, but they 
do not relish being castigated indiscriminately. 
In the nature of their situation all their errors 
become public as soon as they are made not a 
very enviable position at best. They may 
broadcast beautifully for weeks, and nothing is 
thought of it, but let there be a two-minute 
difficulty, and a few score of listeners who never 
thought of giving them a word of praise, let 
fly with both fists. 

Radio has one other drawback; now that it 
has become a public plaything, one can never 
drop it. One's best girl insists on discussing 
the causes of blasting in loud speakers, 
one's brother-in-law wants to know how to get 
some tubes at a discount, the superintendent's 
set, which is out of order, has to be fixed before 
he can be persuaded to send up a little heat, the 
very bus boys and bootblacks inquire what is 
the best set to buy, how much it will cost, and 
whether it will receive Mars every night. 
Popularity has its disadvantages. A high 
official of one of the great corporations in the 



Pity the Poor Broadcaster 



139 



field, leaving on his vacation for parts unknown, 
remarked gloomily: 

"No one's been told where I'm going, and I 
don't know a soul there. I'm going to tell 
everybody I'm a plumber, so they won't talk to 
me about radio." 

There are few radio men who would not 



sympathize with this sentiment at times. At 
bottom all of them including the writer of this 
jeremiad, like the business, "business," observe, 
not "game," for none of them is observed 
leaving it. Like newspaper work, it is fast, 
eventful, and fascinating. So we leave plumb- 
ing to the plumbers, who don't seem to mind. 



A Correction 



WE REPRODUCE in Fig. i the Kauff- 
man circuit as originally published, by 
Mr. Kauffman, in a recent issue of The Radio 
Globe, the Saturday radio supplement of what 
was then the New York Evening Globe. We 
regret that this circuit was incorrectly drawn 
in the trick circuit article, which appeared in 
the March RADIO BROADCAST. 



The principal electrical difference between 
Fig. 2 and the circuit first published, is the 
failure to indicate the inductive relation be- 
tween the plate and grid coils which, however, 
was described in the text of " The Truth About 
Trick Circuits." The interested reader will 
find it worth while comparing the circuit in 
Fig. 2 with the original text. 




FIG. I 

The diagram, Fig. 6 in "The Truth About Trick 
Circuits" in RADIO BROADCAST for March. This 
was published as the Kauffman circuit. See Fig. 2 



/ 


i; / l ' 


ITl ** 



#*s< 




FIG. 2 
The corrected Kauffman circuit 



'HAT the English listener hears, what he has to hear it with, how 
much it costs, and some remarks about the radio climate are in 
W. H. Gary's "England's Venture into Broadcasting" which will 

appear in July. 




The "lab" department has been inaugurated by RADIO BROADCAST in order that its readers may 
benefit from the many experiments which are necessarily carried on by the makers of this magazine in 
their endeavor to publish only "fact articles" backed by their personal observations. 



THE TWO-ELECTRODE VALVE AND REFLEX SETS 



rnpKHE 
filai 
alte 

for 

J^- nrn 



two-element vacuum tube (a 
filament and plate), as a rectifier of 
alternating current, has been known 
for many years. Its rectifying 
properties were probably first noted 
by Edison several decades back whereupon its 
action was named the " Edison effect. " Later, 
this principle was applied to the detection of 
radio signals by Fleming, in England, his tube 
being known as the Fleming Valve. This 
"valve" now finds its largest commercial 
application in storage battery chargers such as 
the Tungar and Rectigon. 

In the triumph of the DeForest audion, 
which followed the introduction of the third 
element or grid, the Fleming valve practically 

CRYSTAL 



\ 




FIG. I 

The principle which may be followed m substituting a 
two element valve for the crystal detector in any circuit 



disappeared from the field of radio detection 
when it had barely developed beyond the 
laboratory stage. However, when the crystal 
detector became popular in reflex and certain 
other radio-frequency amplified circuits, the 
two-element bulb again suggested itself as a 
detecting possibility. It is more sensitive and 
stable than the crystal, and possesses the same 
admirable rectifying qualities which result in 
absolute purity of tone. 

There are several commercial two-element 
valves on the market, and they may be added 
to any crystal rectified set by substituting for 
the mineral as shown in Fig. i. The leads A 
and B should be reversed in order to determine 
the correct directional flow of current. 

Though an extra A battery is indicated in 
Fig. i, it will often be possible to utilize the 
same battery that lights the amplifying tubes 
but this may require some experimenting. In 
using the common A battery, our tests have 
shown that the best results are secured by 
means of an unusual series filament connection, 
(Fig. 2). The filament of the two-element 
bulb is placed in series with the negative fila- 
ment lead to the regular amplifying tubes. A 
3o-ohm rheostat is placed in shunt with the 
valve to regulate the current passing through 
it. Operated in this manner, the extra bulb 
is lighted entirely without additional cost. The 
energy which ordinarily would be dissipated 
and wasted in heating the rheostat, now lights 
the extra filament. 

The remaining rectifying connections must 



In the R. B. Lab 



141 




TO AMP. FILAMENTS 



<t 

+ 



FIG. 2 

The series filament connection recommended by the 
R. B. Lab. Ri is the regular filament rheostat. Con- 
nected in this manner, the extra rectifying tube is operated 
with absolutely no additional expense 



be "doped out" by the operators of individual 
sets, by following out the principle suggested 
in Fig. i, and by noting the manner in which 
this laboratory has effected the change in the 
famous one-tube reflex circuit. 

THE TWO-ELEMENT VALVE AND THE KNOCK- 
OUT REFLEX 

IN THE first place, the use of the commercial 
types of two-element valves is not practical 
in the case of single tube reflex sets. It is not 
possible to take advantage of the big jump 
in efficiency by the "free" lighting of the 
additional filament. The 
commercial diodes consume 
in the neighborhood of f 
ampere, while the tubes used 
in these sets draw | ampere 
or less. 

It is obvious that to oper- 
ate most efficiently (the best 
result at the lowest possible 
cost), the one-tube reflex 
with a two-element bulb rec- 
tifier, the rectifier must be of 
the same amperage as the 
main tube, and of a lower 
voltage, so that it may be 
lighted in series with the 
main tube using up the 
spare voltage difference that 
exists between the battery 
voltage and the operating 
voltage of the tube. The 
operating voltage of the UV- 
2oi-A is 4^, and, when a six 
volt storage battery is used 
to light the filament, i| volts 
are left over, generally to be 
wasted in the rheostat. 



Even though commercial two-element valves, 
meeting these requirements, are not to be had, 
the matter is easily solved by making your own 
rectifying tubes, with the correct amperage to 
order. 

"MAKING" YOUR OWN TWO-ELEMENT TUBE 

IT IS only necessary to procure a standard 
three element tube of the required voltage 
and amperage. The plate and grid are con- 
nected together, and this common connection is 
used as the plate terminal of the rectifier. The 
result is a rectifying tube that our experiments 
have shown to be superior to the usual com- 
mercial two-element valve. 

If the UV-20I-A, or the C-3OI-A, operated 
from a six volt battery, is the main tube in the 
single bulb reflex (which, incidently, is the best 
possible arrangement, for voltages up to a 
hundred and twenty may be used without dis- 
tortion), the rectifier tube may be a WD-i i or 
-12, or a Western Electric "N" tube (Fig. 3), 
with the plate and grid bridged as we have 
directed. The connections for this ultra ef- 
ficient arrangement are indicated in Fig. 4. 

The use of the WD tubes and the UV-igg, as 
a main-tube-rectifier combination is not so 
practical due to filament complications. HOW- 




FIG. 3 

Back view of the R. B. test set. Comparing a commercial two element valve 
with a Western Electric "N" tube and crystal. Note the two unused 
binding posts. This being a test set, room was provided for expansion 



142 



Radio Broadcast 




FIG. 5 

A front view of our experimental set. A very neat layout, 
using a seven by ten standard panel. Antenna and ground 
binding posts are on the left, with output posts on the right 



ever, if the possession of these tubes makes this 
combination particularly convenient, the UV- 
199 should be used as the main tube, and the 
WD-i i or -i 2 as the rectifier, with an extra dry 
cell connected as shown by the dotted line in 
Fig. 4. Be sure to follow the indicated polarities. 
The two A batteries are "bucking" each other 
(positive to positive), but are connected pur- 
posely in this manner. This extra battery 



connection also applies to 
the use of the commercial 
two-element valve such as 
the "Diode." (Employ our 
connections rather than 
those suggested in the cir- 
cular accompanying that 
tube.) 

If identical tubes are em- 
ployed, for instance a 
WD-I2 for main tube and 
another, with plate and grid 
bridged, for rectifying, the 
series filament connection is 
still used, but the A bat- 
tery voltage is doubled. 

The best possible com- 
bination is that first men- 
tioned, i.e., the UV-2OI-A 
as the main tube, and a 
i^-volt, j-ampere tube as 
the rectifier, the series fila- 
ment being lighted from a 
single six volt battery. 

Care must be observed to follow the initialed 
connections to the audio-frequency amplifying 
transformer, T^. 

A marked improvement in selectivity, due to 
increased functioning on the part of T2, is 
noticed when using tube rectification. The 
circuit is also more stable, and the telephone 
shunt condenser, 3, a .002 mfd. Micadon, 




FIG. 4 

The circuit of our one-tube reflex plus two element valve detection, a more selective and sensitive set 
than the former " Knock-Out" set with a crystal detector. The extra filament costs nothing to operate 



In the R. B. Lab. 



143 




Testing the two element valve arrangement, plus a three stage resistance-coupled audio 
amplifier the ideal combination. Incidentally, a partial view of radio station 2 PI 



may be used with beneficial results, without 
inclining the circuit toward oscillation. 

COMMERCIAL INDUCTANCES AND 
THE ONE-TUBE REFLEX 

THE windings Ti and T2 of diagram Fig. 
4 may be those described in the One 
Tube Knock-Out Reflex article appear- 
ing in the April RADIO BROADCAST, or may be 
two of several types of commercial inductances 
now on the market. These latter will appeal 
to enthusiasts who, for various reasons, do not 
care to wind their own coils. 

Ti (right, in Fig. 3) is an enclosed inductance 
made by the Ray-Dee-Artcraft Instrument 
Company, Redlands, California, known as a 
"Tuned R. F. Reflex Transformer." T2 is a 
standard neutroformer type coil, purchased 
from the Teale Supply Company, New York 
City, with the primary rewound. While we 
have found that the boxed inductance used as 
Ti is best suited as the antenna coupler, neu- 
troformer type coils, with rewound primaries, 
may be employed both as Ti and T2. The 
primaries should be rewound (assuming an ap- 
proximate winding diameter of 2 inches) with 
15 and 35 turns respectively Ti and T2. 



Due to the small space provided for primary 
winding on the Workrite neutroformer, the pri- 
mary of T2 is best wound over the outside of the 
secondary. 

Figs. 3, 5 and 6 show various views of the set 
on which the tests described in this article were 
made. A clip, shown in Fig. 3, was used in 
changing quickly from crystal to diode de- 
tector. 




FIG. 7 

The Colpitts Oscillator, which can be changed 
to a very efficient circuit by adding the Reflexit 



144 



Radio Broadcast 



THE REWIRED COLPITTS 
OSCILLATOR 



THE REFLEXIT 




THE 



The complete circuit the re-wired blooper 
plus the Reflexit. This is a real receiver 

REFLEXIT AND THE COLPITTS 
OSCILLATOR 



IN THE early days of broadcasting, before 
the evil possibilities of radiating receivers 
were appreciated, the Colpitts oscillator 
became very popular as a receiving circuit. 
Particularly recommended to home builders by 
its simplicity, it being probably the most easily 
constructed of all receivers, it was widely 
described under a hundred different names, 
and built by a hundred thousand enthusiasts. 
This circuit (which is actually a transmitting 
system, and designed as such) is shown in Fig. 
7, and some of the names under which it has 
insinuated itself into an all too general use are, 
"The Simplex," "The Peterson Automatic 
Regenerative," "The Flivver," etc. A fuller 
description of its characteristics and evils will 
be found in " The Truth About Trick Circuits, " 
appearing in the March 
RADIO BROADCAST. 

This circuit, which has 
been exiled by all consider- 
ate enthusiasts and dealers, 
can be reclaimed from the 
ash-can by the use of the 
Reflexit, described in this 
magazine last month. By 
making a few changes in the 
Colpitts circuit, and adding 
the Reflexit, this radiating 
receiver is transformed into 
a single tube reflex set a 
real DX receiver, of mar- 
velous quality, signal 
strength, and superior se- 
lectivity. The new set. 



The May RADIO BROADCAST con- 
tains detailed instructions on how 
to make the Reflexit, and adapt it to 
the tickler feedback single-circuit 
blooper. It may be added to the 
Colpitts Oscillator with equal sim- 
plicity. 

REWIRING A COLPITTS SET 

THE first thing to be done is to 
disconnect all instruments in 
the set leaving the receiver as if 
it had never been wired. In the 
Colpitts Oscillator, Fig. 7, L is gen- 
erally a coil of wire, wound with 
one hundred turns on a three inch 
form, and tapped, perhaps, every 
ten turns. Sometimes L is an untapped coil of 
about sixty turns of wire, tuning being accom- 
plished by varying the capacity of condenser, 
C. In either case, a layer of paper is placed 
over this coil, L, and a primary of twelve turns 
is wound with about No. 22 wire, over the 
paper. If a two and a half inch tube was 
originally used as the winding form, wind the 
primary with fifteen turns of wire; if a three 
and a half inch form, wind ten turns. 

It now remains only to rewire the set accord- 
ing to the diagram, Fig. 8. If L is an untapped 
coil, it is connected across the condenser (the 
former capacity feedback variable) as shown by 
the dotted line. The instruments to the left 
of the vertical dotted line represent those 
salvaged from the old single-circuit blooper. 
Flexible leads, in the rear, connect the reflexit 
with the rebuilt tuner. 

The Reflexit combinations will work best 




FIG. 9 

The Reflexit is on the right 



In the R. B. Lab. 



145 



with the UV-199, -299, UV-2OI- 
A and the 0301 -A tubes. 

Figs. 9 and 10 show front and rear 
views of the completed combination, 
which is the famous single-tube re- 
flex circuit. The apparatus photo- 
graphed and described possesses 
remarkable selectivity and volume, 
far exceeding those qualities in the 
original single circuit receiver. In our 
laboratory, it brought in all local sta- 
tions on the loudspeaker (with real 
intensity) and not merely permitted 
excellent selectivity among WEAF, 
WJZ, WJY, and WHN (all locals), 
transmitting at the same time, but 
brought in KDKA on phones, 
through the local bedlam. 

BUILDING YOUR OWN LAB 



THE gasoline torch is a labora- 
tory essential, and this month, it is our 
suggested addition to the growing labora- 
tory. A small torch will cost between three and 
five dollars. Do not compromise with quality, 
but purchase a reliable torch, paying a higher 
price for it if necessary. Nothing but the very 
best, should go into the equipment of the radio 
laboratory. It is cheaper in the long run, and 
safer all the way around. 

Fig. 1 1 shows a torch of the most convenient 
size. It is small, as compared with the hand 
holding it, and yet is capable of very heavy 
work. Its uses are many, but it will probably 
prove its genuine value on out-of-doors solder- 






FIG. 10 

The rear view of the Reflexit combination 



FIG. I I 

small torch, but one capable of quite heavy work 

ing. Engineers have reiterated the necessity 
of soldered joints in the antenna and lead-in 
connections, which, however, are almost im- 
possible to effect with a rapidly cooling iron, 
working on the unheated wire. The gasoline 
torch may be described as indispensable in the 
erection of an efficient antenna. 

It also has many laboratory uses. The torch 
is generally fitted with an iron holder, for the 
heating of the ordinary soldering iron. This is 
particularly convenient for experimenters, 
whose shops are not equipped with electric 
soldering apparatus. The electric soldering 
iron, however, is much to be preferred wherever 
practicable. 

The iron can only be used 
efficiently when soldering 
small objects. For solder- 
ing on wire of size lower 
than No. 8, B. & S., and on 
fire escapes, waterpipes, etc., 
the torch is absolutely 
necessary if a good joint is 
to be made. 

USING THE TORCH 

THE individual instruc- 
tions of each manufac- 
turer for the operation of 
his torch should be carefully 
observed and followed. 
When the basin is first 
lighted, the gasoline will 



146 Radio Broadcast 

probably have trickled down along the torch, The flame should be used at full blast only on 

to the floor, and for a moment there will be an very cold or large objects, 

alarming and general conflagration. However, An asthmatic or sputtering flame indicates 

count ten before you send in the fire alarm, and that gasoline is low. A weak but constant 

all will be well. flame means lack of pressure a few swift 

In soldering large and cold objects, the metal pumps are necessary. 

should be enveloped in the tip of the flame, and In operating the torch out-of-doors, the blast 

warmed until it will melt solder. The flame is should be maintained considerably higher than 

then moved slightly to one side, or played upon in the laboratory, even on small work. This is 

it from a distance, so that the hot metal, and to keep the needle valve from cooling in the cold 

not the flame, melts the solder. air and wind. 



Market Information and Weather Forecasts from Central 

States Radio Stations 

U. S. Department of Agriculture, Weather Bureau. 

Program for Broadcasting Weather Fore- 
casts and Reports by Radio Illinois Section 

9Oth Meridian Standard Time 
All are Radio Telephone Except Great Lakes 

NAJ, Great Lakes: (telegraph) (151 Kilocycles) 9:15 A. M. morning lake forecasts, aviation 
forecasts; 4:00 p. M. special warnings; 9:30 p. M. evening lake forecasts, aviation fore- 
casts. 

KYW, Chicago: (560 Kc.) 12:00 noon, (i i :oo A. M. during local " Daylight Saving") morn- 
ing local forecast, state forecasts, lake forecast; special warnings at 2:15 and 4:15 P. M.; 
9:25 to 9:30 P. M. evening local forecast, state forecasts, lake forecast. Monday, 
"silent night. " 

WAAF, Chicago: (1049 Kc.) 10:30 A. M. morning local forecast, state forecasts, general 
forecast, general weather conditions, aviation forecasts, shippers' advices during winter 
season, national weather-crop summary and state summaries on Wednesday during crop 
season; 12:30 P. M. repeats the 10:30 A. M. information, also weekly outlook issued on 
Saturday. 

WDAP, Chicago: (833 Kc.) 10:00 A. M. morning local forecast, state forecasts; 10:00 p. M. 
or later, at end of regular program evening local forecast, state forecasts, lake forecasts, 
general forecast, general weather conditions. Monday, "silent night." 

WOC, Davenport: (620 KC.) 1 1 :oo A. M. morning local forecast, state forecasts, river fore- 
cast, general weather conditions, state weather-crop summaries on Wednesday; special 
cold wave warnings sent as flashes. Tuesday, "silent night." 

WJAN, Peoria: (i 170 Kc.) 9:15 A. M. morning local forecast, state forecast, shippers' fore- 
casts; repeated at 1 1 :3O A. M. 

WEW, St. Louis: (1150 Kc.) 10:00 A. M. morning local forecast, state forecasts, general 
weather conditions, river forecasts; special warnings at 5:00 p. M. 

KSD, St. Louis: (550 Kc.) 10:40 A. M. morning local forecast, state forecasts, general 
weather conditions, river forecasts and stages; special warnings at 12:40 p. M., i '.40 P. M 
and 3:00 P. M.; 10:00 P. M. evening state forecasts. 

Amateurs receiving weathei forecasts are requested to advise (by mail) Weather Bureau Office, 
Springfield, 111., of the quality of service received and how distinctly the stations are heard. 



Adventures of a Wireless Free-Lance 



A Thrill that Came Thrice in a Night-time 
By GEORGE F. WORTS 



WHAT tales they could tell if 
wireless operators only dared ! 
No wide-awake lad can ham- 
mer brass on the high seas 
for very long without collect- 
ing a fund of delicate information which he will 
refrain from putting into his memoirs. The 
oath of secrecy to which he solemnly swore 
when he obtained his license placed a seal 
upon his lips and an emergency brake upon his 
pen. If he confided his secrets to the public, 
his license might be revoked; he might be 
summoned to answer embarrassing questions 
in court; he might even spend some 
time manufacturing brooms or auto- 
mobile license plates. He might, in 
any event, cause some one a great 
deal of trouble. 

The traveling public has always 
looked upon the wireless man as a 
mystery man; and that attitude is 
the correct one for the traveling 
public to take. A wireless operator 
is, in a sense, a walking Pandora's box! 

1 know one operator, now on a Transpacific 
run, who dares not tell what he knows concern- 
ing a certain shipwreck in which several lives 
were lost because of another operator's negli- 
gence. The negligent operator went to a salty 
death proclaimed a hero. Further details in 
that case 1 cannot safely divulge. 

The war came after my time, at sea, but I 
am sure that a great many of the wireless men 
who served during that adventurous period 
must fairly be bursting with secrets. 

What goes on inside an operator's head- 
phones is sacred. Wild horses could not drag 
from me some of the things I have plucked out 
of the air; but I do not believe I will be violating 
the spirit of my old oath in relating the story 
of the three distress signals that came my way 
in a single night. It happened a good many 
years ago; the actors in that far-flung drama 
are scattered now to the four quarters of the 
globe; no one, so far as I am aware, made any 




mistakes; and, just to be on the safe side, I will 
refrain from mentioning the names of the ships 
which took part. Some facts I will disguise, 
but the conditions tmd sensations of that night 
I will reproduce as faithfully as 1 know how. 

1 was at that time the second operator on a 
large fast ship which we will call the Saurian, 
although any Pacific coast operatorwho chances 
to read this article will penetrate my secret in a 
jiffy. 

The Saurian had the honorary title, in wire- 
less circles, of "supervisor ship." She ran 
on a regular, close schedule between San 
Francisco and Honolulu. Her wireless 
house was a square bump on the boat 
deck just abaft the funnel and it 
boasted a wireless installation proba- 
bly very similar to the one with which 
Noah equipped the Ark. Judged by 
present standards it was, at all events, 
antique and quaint. The transmit- 
ting set comprised a two-kilowatt 
open core transformer of the United 
type, a battery of Leyden jars 
mounted in a handsome imitation mahogany 
cabinet for a condenser, a helix of silver-plated 
copper tubing, and a rotary spark gap driven 
at about three thousand r. p. m. and producing, 
when received, a mellow melancholy note. It 
was the sweetest spark I ever heard. Ourwave- 
length was somewhere in the neighborhood of 
600 meters, although nobody knew and nobody 
cared. The set was a freak. It had a tremend- 
ous range. That antique transformer con- 
sumed, I am sure, more than forty amperes; and 
we had amazing radiation. Because of our 
phenomonal sending range and the express- 
train regularity of our schedule, the Saurian 
had become the Pacific supervisor ship. That 
is to say, we had the authority of a land sta- 
tion over other ships within range. We relayed 
an immense amount of traffic and were sup- 
posed to supervise the radio manners of our 
brethren. It goes without saying that the 
operators on the Saurian were keenly aware 



Wireless 



i 4 8 



Radio Broadcast 



of their importance, and heartily disliked 
by all. 

On the run with which this chronicle is con- 
cerned, we pulled out of San Francisco on a 
nasty gray day in the teeth of a stiff head 
wind. Wind pressure ran up to fifty miles an 
hour before we were abreast of the Farallones; 
and two days later, as we plunged and wal- 
lowed westward, we ran head-first into a howl- 
ing eighty-mile gale. All afternoon we plunged 
and pitched and corkscrewed. The first opera- 
tor came off watch at midnight, limp and green- 
ish of complexion, and I went on the 
job in a state of mind and stomach 
even more pronounced. 

Everything that could come loose 
in the wireless cabin had already come 
loose. Spume was flying the length of 
the ship with the stinging force of hail. 
The full-gale howled in the funnel 
ju\'s and aerial wires. The wire- 
less cabin rose and fell with that swooping 
sensation peculiar to express elevators in forty- 
story buildings. We were five decks above the 
water line. 

It was a bad night on the air as well. When 
I put on the phones and adjusted our car- 
borundum detector, static came sputtering in. 
It was faint and distant but persistent enough 
to interfere with long .distance work. KPH 
and KPJ, the San Francisco and San Pedro 
shore stations, were droning out storm warn- 
ings for the entire Pacific coast; but business 
proceeded as usual. I relayed a string from an 
incoming Jap boat to KPH and another batch 
from KPH to the Sonoma, a Union Liner in the 
Australian service, a day out of Honolulu, east- 
bound. 

Then quiet, save for the static, descended for 
almost an hour. A copy of my log for that 
night, which I preserved for years, was des- 
troyed recently in a fire, and I must rely upon a 
somewhat unreliable memory. Shortly before 
two o'clock everybody seemed to get busy at 
once. The lap had another string for me to 
shoot along 'to KPH. KHK (Honolulu Mar- 
coni) wanted me to relay a batch to KPH 
he couldn't work him direct because of the 
static and ships all over the Pacific were 
buzzing away. As I recall it, from two to three 
o'clock in the morning was always the busiest 
hour of the night on the Pacific. 

And through that busy buzzing I suddenly 
heard a far-away, whispery SOS or be- 
lieved 1 did. I immediately called Frisco and 



asked him if he had heard an SOS. He replied 
that he had not, and told me to send a "CQ" 
which meant, in those days, "All stations stand 
by!" The list of international "Q abbrevia- 
tions" had not then been adopted. But a CQ 
was not needed. Following my brief query to 
KPH and his answer, the air cleared magically. 

THE NIGHT: THREE s o s CALLS 

1 STOOD by for orders from Frisco, and after 
a moment he told me that he still heard 



nothing. 




I knew he had not heard, for, long be- 
fore he started to send, the faint, 
far-away, whispery spark was calling 
again. It was so faint that the shud- 
dering of our ship obliterated it; so 
faint that it hardly reached me 
through the scratching of the static. 
Somehow I had always pictured a ship 
in distress as being conveniently 
near, and the faintness of this 
spark made me believe that the whole Pacific 
Ocean lay between us. For all practical pur- 
poses, it did. 

While I was straining my ears to catch his 
call letters, a vigorous, clear, crisp buzz filled 
my 'phones. 

" SOSSOSSOSdeW- 
A second ship calling for help before I could 
even identify the first one! The next half 
hour was destined to be the busiest I had ever 
lived. Within that half-hour, there were three 
of them. The gale must have dropped down 
from the sky and struck the entire Pacific at a 
single blow. 

If you will glance at a map of the Pacific 
Ocean and make a mark one third of the way 
from San Francisco to Honolulu on the course 
which ships on that route follow, you will 
know the approximate position of the Saurian 
on that terrible night. 

"Can you hear either of them?" I snapped 
at Frisco. 

"Don't hear anything but static!" Frisco 
snapped back. 

In an interlude between splashes of static I 
caught the call letter that the far-away whis- 
pery spark was sending, and a glance at my list 
of calls identified it as a fishing boat. The 
second distress call had been despatched by a 
tramp freighter. 

For a moment I didn't know what to do. 
Then I sent a general CQ; told the tramp to 
stand by and the fishing boat to report his 
position; and I will never forget the agonizing 



Adventures of a Wireless Free-Lance 



149 



faintness of that distant, husky, faltering 
spark. 

It was necessary for him to repeat each word 
three times, and even this laborious procedure 
left blanks that I filled by guesswork. Repeti- 
tion in transmission when you are in a hurry is 
always irritating, always nerve-wracking; and 
on that occasion, as I tried to read that whisper 
of a sound and to shelter it with cupped hands 
from the rumbling of the Saurian, the squeak- 
ing of the wireless room woodwork and the 
shouting of the wind, it was maddening. 

" Have not seen the sun in days," he painfully 
pounded out, "and have been blown so far off 
our course we can only guess where we are. 
Captain says we are about Lat. ; Long. 

The exact position figures I do not recall. It 
does not matter, for no one ever verified them. 
At all events, the distressed fishing boat was 
about seven hundred miles north of us. I 
asked him about his condition. 

"We are in very bad shape," the faint 
whisper answered. " Forward cabin smashed 
in. All boats gone and only one raft left. 
Pumps can't keep up with water. Fireroom is 
flooding. We are lying to, with engine turning 



asking for a report from any ship within run- 
ning distance of the distressed fishing boat and 
no one answered. For ten minutes I pounded 
away, trying to raise some one; and that was 
the beginning of the most real tragedy I have 
ever experienced. Perhaps my imagination 
cut the thing out of whole cloth, but, as I saw 
it, there was I, carrying on conversation with a 
man who might, in the next breath, be strangl- 
ing to death in icy salt water; and the Saurian, 
apparently the nearest source of help, was two 
days at full sea speed away from him! 

In answer to my further calls, presently a 
shrill whine was -heard. It was a Nippon 
Yusan Kaisha boat, a Jap, on the Seattle- 
Yokohama-Hong-Kong run. 

"Four hundred miles due south of him. 
Advise," said the Jap. 

" Keep in touch with him and try to raise 
some ship nearer to him," I answered. 

And it was then that the third SOS of that 
packed half-hour came droning in this time 
an oil tanker. The operator gave me his 
position without having to be asked for it. 

"Away off our course, but estimate Lat. ; 

Long. 



NOTICE 



DEPARTMENT OF COMMERCE 

BUREAU OF NAVIGATION 
RADIO SERVICE 



SECRECY OF MESSAGES-FALSE SIGNALS 

The act of Congress to regulate radio communication, approved August 13, 1912, provides in the nineteenth regulation 
and in the seventh section, respectively, as follows : 

Nineteenth. N"o person or persons engaged in or having knowledge of the operation of any station or stations, shall 
divulge or publish tlie conteutsof any messages transmitted or received by such station, except to the person or persona 
to whom the same may pe directed, or their authorized agent, or to another station employed to forward such message 
to its destination, unless legally required so to do by the court of competent jurisdiction or other competent authority. 
Any person guilty of divulging or publishing any message, except as herein provided, shall, on conviction thereof, be 
punishable by a flne of not more than two hundred and fifty dollars or Imprisonment for a period of not exceeding three 
months, or both fine and imprisonment, in the discretion of the court. 

******* 

SEC. 7. That a person, company, or corporation -within the jurisdiction of the United States shall not knowingly 
alter or transmit, or cause to be uttered or transmitted, any false or fraudulent distress signal or call or false or fraudu- 
lent signal, call, or other radiogram of any kind. The penalty for so uttering or transmitting a false or fraudulent 
distress signal or call shall be a fliie of not more than two thousand five hundred dollars or imprisonment for not more 
tthan live years, or both, in the discretion of the court, for each and every such offense, nnd the penalty for so uttering 
or transmitting, or causing to be uttered or transmitted, any other false or fraudulent signal, call, or other radiogram 
phall be-a fine of not more than one thousand dollars or imprisonment for not more than two years, or both, in the 
Discretion of the court, for each and every such offense. 

(TO BE POSTED IN RADIO STATIONS) 

A FACSIMILE OF THE ORDER OF SECRECY 
Which is displayed in every radio operating cabin 



only enough to head us into it. Old man 
wants to know how soon you can get help to 
us. We won't hold together many hours." 

TRAGEDY JOO MILES AWAY 

IMAGINE having that responsibility placed 
1 personally on your shoulders by a man seven 
hundred miles away! I sent out a query 



I reached up and made another mark on our 
chart of the Pacific. The oil tanker was ap- 
proximately five hundred miles away, in a 
southeast by south direction. 

" KPH," I called, "can you hear W ?" 

"Can't hear anything but static," Frisco 
replied. " Handle them all." 

I called for a condition report from the tanker. 



Radio Broadcast 



" Rudder is jammed," was the answer. 
"On our beam ends in the trough. Danger 
acute. SOS SOS! Must have help at once!" 

Then: 

"SOS! SOS! SOS!" buzzed the tramp 
"Sinking! Send help!" 

The shrill whine of the Jap stopped and I 
could hear the fishing boat's despairing whis- 
per: 

" SOS! SOS! SOS! Somebody please 
answer!" 

It was dreadful! 1 desperately told the 
fishing boat to continue calling; the 
oil tankers to shut up and stand by; 
the tramp to give me position and 
condition. 

He gave his position, and I made 
another mark on our chart of the 
Pacific. He was approximately twelve 
hundred miles northwest by west 
of Cape San Lucas, which is the 
lowermost extremity of the pen- 
insula of Lower California, or about 
six hundred miles southwest of the Saurian. 

" Wave stove in hatch-cover in forward deck- 
well hour ago. Hold flooding. Bow almost 
submerged. Waves breaking all over us. 
All boats smashed or lost. Must have help 
quick." 

1 asked if any ship was near him. There was 
a prompt answer from a Pacific Mail passenger 
boat in the San Francisco-Panama express 
service. 

"Am about forty miles southeast of him. 
Any one any nearer?" 

It appeared that no one was nearer. I in- 
structed the Mail boat to deal with him; then 
went to work on the oil tanker. I sent out the 
usual query, asking any ship near him to 
answer. There were three replies. The near- 
est ship was a Blue Funnel, a British freighter, 
between fifty and sixty miles northwest of him. 
I told the Blue Funnel and the oil tanker to 
work it out between them. 

You may be wondering why the Saurian 
acted in a supervisory capacity in the handling 
of those three distress calls; and tire reason is 
interesting. I do not believe that three dis- 
tress calls received simultaneously under ex- 
actly those conditions would be handled in that 
fashion to-day. They would be handled in- 
dividually and simultaneously by the ships 
nearest the distressed vessels. In those days, 
tuning-out interference was much more difficult 
than it is to-day, for three reasons. To-day, 




the transmitting sets of all ships are much more 
sharply tuned; a variety of transmitting wave- 
lengths is available; and receiving apparatus 
is much more selective. If 1 had not super- 
vised all transmission very rigidly that night, 
no one could have worked through the jam. 
We were all working on six hundred meters, 
and our waves were very broad. 

Now, all of this may sound cool and orderly, 
but permit me to state that there was nothing 
cool or orderly about the state that my mind 
was in. The crisis had turned me into an 
automatic nervous machine. 1 was so 
panicky that I had to grip the key 
firmly with the fingers of my right 
hand and hold my right elbow steady 
with my left hand. Nor was the state 
of my nerves eased by the plunging, 
- the pitching and the corkscrewing of 
the Saurian, the squeaking of the 
woodwork, or the howl of wind 
and hiss of spray. My chair was 
lugged down to the floor, and my 
legs were wrapped tightly about the chair-legs 
or I would have been catapulted out of it. 

HOW THEORY DIFFERS FROM COLD FACT 

A-TER the arrangements had been made for 
the relief of the oil tanker and the tramp I 
must have sat for fifteen minutes with both 
hands clamped over the phones, forcing them 
down on my ears, trying to collect my wits. 
1 have often imagined other operators 1 have 
known men who are calm and cool and re- 
sourceful going through that ordeal with a 
steady hand and a steady eye, logging it all up 
as they went along, crisply reporting each event 
as it occurred to the officer on watch, as a 
well-trained operator should do. It would be 
pleasant to paint a picture of myself as that 
sort of hero. But I wasn't a hero in any 
respect; I was a quaking, terrified, blundering 
kid, forced by circumstance into a position of 
tremendous responsibility that I would have 
eagerly shirked. Later on, in my capacity of 
nine-day wonder, I assumed a lofty, nonchalant 
pose in static rooms; looked down upon or- 
dinary operators with a great deal of disdain, 
and admitted under their bombardment of 
questions that the emergency had found me 
brave and composed; but the twenty or thirty 
operators who were listening in within range 
of the Saurian that night knew me for the 
monumental young liar that I was! I make 
my confession now without the slightest 



Adventures of a Wireless Free-Lance 



embarrassment. But let us get on with the 
story. 

The Blue Funnel reported that the captain 
had changed her course and was going to the 
rescue of the oil tanker The Pacific Mail 
boat reported that she was steaming full speed 
to the aid of the crippled tramp. And the 
Nippon Yusan Kaisha reported that the fishing 
boat no longer responded to his calls. 

The rest of the night the Jap and I devoted to 
trying to raise the fishing boat or any ship 
within short running distance. The operator 
of the fishing boat did not reply again. 
In those days some ships carried only 
one operator, whose duties were 
divided between working the radio 
and some other kind of ship's busi- 
ness. I had hoped that the operator 
of such a ship might listen in some- 
time during the night; but no one 
answered. We were probably still 
appealing for help long after the fishing boat 
broke into pieces. 

The night was practically gone when my 
nerves really gave way. KPH called me and I 
tried to answer, but my hand would not work 
the key. 

DID THE NIGHT SWALLOW GROPING MESSAGES? 

EVERY nerve in it seemed dead or discon- 
nected. The thought of the fishing boat 
going down that operator, with whom I had 
been talking, trying vainly to be of some help, 
probably a dead man by this time made me 
limp and dizzy. I hated the sea as 1 have 
never hated it before or since. I made up my 
mind never to go to sea again. But 1 did, of 
course. You always do. And I hated static 
that night, too, more than I have ever hated it 
before or since. I have always thought that 
that man was trying to tell me something that 
the static would not let me hear. He kept on 
sending. The Jap, with his poor understand- 
ing of English, must have missed the sense of 




it. Did he send some message that no one 
received just before his ship went to pieces? 
That I might have missed such a message is 
one reason why I have told this story to very 
few people. . . . 

Day was breaking when I went out on deck 
for a breath of fresh air. The force of the 
gale was broken, but mountainous waves were 
rolling down upon us from out of the misty 
grayness. Spray stung my face and spattered 
hissing on the hot funnel. It did not seem pos- 
sible that a ship as large as the Saurian could 
roll and plunge so and not rip apart. 
Every moment she staggered and 
thundered as waves piled completely 
over the peak. 

The second mate came aft, lurch- 
ing from one permanent object to 
another. He gave me a glare as he 
approached. He was a grizzled old 
timer, a relic of sailing ship days the 
kind of ship's officer who thinks that wireless op- 
erators are insulting reminders of a mechanical 
age that is taking more and more of the kingly 
authority out of the hands of the men who 
navigate ships. He stopped near me and 
bawled above the wind: 

"Say! What in hell are you doing away 
from your post? Don't you know you be- 
long in there with those things on your 
head? How do you know but what ships 
are in trouble all over the Pacific in weather 
like this?" 

Well, that's the life of a wireless operator. 
Anyhow, it was in those days. Maybe times 
have changed. 

The fishing boat was the only complete dis- 
aster of the night. Parts of her were found 
floating about the sea, but none of the crew 
was saved. The Blue Funnel towed the tanker 
back into Honolulu for repairs; and the Mail 
boat took the crew off the freighter. She was 
still floating when they got away, but went 
down before ni;ht. 



<T2EADERS of this magazine are reminded that our $500 Pri^e Contest on 
\jtbe best answer to the question "H/ko is to Pay for Broadcasting and 
How?" closes on July 2oth. A complete announcement of the terms of the 
contest appears on page 69 of RADIO BROADCAST for May. 




A TRADING POST ON THE MACKENZIE RIVER 

Probably one of the most northerly parts of the world where a radio receiving set is permanently installed. This 
place is just two hundred miles south of the Arctic Ocean. The black outcrops in the river are beds of tar sand 



A Canadian Broadcasting Station 

Interesting Bits About CJCA a Pioneer Station in a Pioneer Country. How 
"Great-Spirit-in Box" Goes Along With the Trader's Rifle, Pemmican, and Tea 

By H. F. MULLETT 



GtAY EAGLE, chief of the Yellow- 
knife Indians who inhabit the 
Mackenzie basin district of the 
Northwest Territories, away up 
at the top of the map of the 
American continent, and a thousand and more 
miles north of Edmonton, the capital city of Al- 
berta, swung his bale of raw furs from his dog- 
sled in front of the fur trader's post, grunted 
an order to his squatting dogs, and entered 
the store. 

" How!" he remarked, in answer to the Scots 
trader's hearty greeting. "Bring furs! How 
much?" 

With rapid appraisal borne of long experi- 
ence, the trader skimmed through the valuable 
pile and named his figure. 

"No good!" grunted Gray Eagle. "Price 
better! ask how St. Louis market from Great- 
Spirit-in-Box!" 

And for two days, until the trader, in his 
lone post a thousand miles from any city, got 
the latest fur prices by radio from CJCA, the 
Edmonton Journal's broadcasting station at 
Edmonton, Gray Eagle waited with true native 
immobility, nor would he part with a fur or a 



pelt until he knew from "Great-Spirit-in- 
Box," how the market was running. 

That's why it is safe to make the statement, 
that probably few broadcasting stations on 
the American continent serve a wider field, 
and for more diverse uses, than does CJCA. 
The station call letters daily reported by the 
Journal operator, G. A. R. Rice, whose son- 
orous announcement that "this is CJCA speak- 
ing CJCA, Edmonton Journal, of Edmonton, 
Alberta, Canada, the sunniest spot in Sunny 
Alberta," has been picked up away down at 
Key West, and, in fact, at many other distant 
places all over the United States. 

From the Montana boundary to the Arctic 
circle, there are but two cities in Alberta where 
long distance broadcasting is done, and of these 
two cities, the work done by the Edmonton 
station is by far the most interesting, by virtue 
of the scope and diversity of its field. CJCA, 
of course, isn't a station in the midst of a wil- 
derness, for Edmonton is a city of 70,000 peo- 
ple, growing rapidly toward the 100,000 mark, 
with half a dozen lines of railway radiating from 
it, and with every modern convenience such as is 
enjoyed by dwellers in any large city in America. 



A Canadian Broadcasting Station 



153 



PIONEER RADIO SERVICE FOR REAL PIONEERS 

BUT because Edmonton is a big and grow- 
ing city practically on the edge of civili- 
zation, its work with radio must necessarily 
be of a pioneer nature, and much of its service 
must be to a people still in the pioneer stages, 
hewing out farm homes from the virgin land, 
building railways into virgin territory, map- 
ping, surveying, exploring, trading with native 
tribes, bending mighty rivers to its will, and 
ever pushing onward and outward even to the 
shores of the bleak Arctic itself. 

The romance of the Edmonton Journal's 
broadcasting lies with that little army of pion- 
eers out almost on the ragged edge of nowhere, 
to whom CJCA means the only link with 
civilization a civilization reached only after 
months of arduous travel in many cases a civ- 
ilization from whence, at long intervals, men 

with mail bags struggle through to 

bring news that may be a year old 
before it reaches its destination. 

But even the farm home, in this 
land of great distances, takes on its 
own touch of the romantic, for 
railroads are still all too few, and 
there are farms to-day, in Northern 
Alberta, fifty, sixty, a hundred, and 
more, miles from any railway. 
What CjCA means to these folks, 
leading the lonely life of pioneer 
settlers in a new land, can be real- 
ized only by those who have shared 
the lot of these pioneer people. 

Out beyond the last thin steel 
line of railway that marks the edge 
of a civilization itself so new as to 
appear actually to the visitor un- 
civilized, goes each year that little 
band of trappers and explorers, 
government surveyors and mis- 
sionaries, prospectors and traders, 
Mounted Police and fire rangers 
to join that other little band already 
there many of them with years of 
pioneerwork to their credit many- 
asking nothing better than to live 
and die in the lone spaces of the 
Northwest. 

And more and more, despite the 
fact that northern travel calls for 
limited equipment, the radio is be- 
ing taken "down north" by these 
men of the frontier. Canoes may 



be small and frail portages long and hard- 
camps a hard day's journey in between snow, 
ice, wind, rain, thaw, fire, and every danger the 
elements may command, may lie in wait at each 
turn of river or trail but the "Great-Spirit-in- 
the-Box" goes along with the rifle, the pem- 
mican, and the tea. 

Down the broad bosom of the mighty Atha- 
basca and Mackenzie rivers, when the spring 
ice has gone out, and all the land is astir with 
life of bird, and tree, and beast, go the govern- 
ment men, forever surveying, mapping, report- 
ing and the black box goes with them. Camp 
at night means CJCA, with its music pro- 
gram, its world news, and maybe, its personal 
message for some one of the party. 

Its use in the fur trade has already been 
indicated. Two years ago when world prices 
in furs dropped heavily and suddenly, traders 
of the north were actually paying more 




THE EDMONTON "JOURNAL" 
Newspaper and radio plant in far-off Albeita 



Radio Broadcast 




for raw furs from the Indian and Eskimo 
trapper, than New York, St. Louis, or Montreal 
was offering. The radio is solving this dif- 
ficulty, and saving thousands of dollars. 

Through thousands of miles of uncharted 
timber, as the hot sun of the short northern 
summer bakes the rotting vegetation dry as 
tinder, goes the fire ranger, pack on back, with 
his faithful dog as companion. He carries 
with him a small receiving set and each night 
after six he strings his wire to a convenient tree, 
and listens to his chief, away up the river at 
McMurray, sending out instructions, giving 
him the news of the country and of the world, 
and maybe ending up with a tune or two on 
the gramophone. 

Already, the Canadian Government, recog- 
nizing the potential value of radio in the north- 
land, has announced its intention of setting up 
a string of stations between Edmonton and the 
Arctic Ocean. One such station is already in- 
stalled, and this year may see a government 
station even on Herschel Island, the Mounted 
Police headquarters for the Arctic. 

Station CJCA has already done good service 
for the police, in sending out urgent messages 



of wanted people, stolen autos, etc. The value 
of this work may be illustrated in the case of 
a foreigner, who was wanted for murder. 
The fugitive was thought to be heading south 
from Edmonton. CJCA broadcast his de- 
scription, and in a few minutes a radio fan in 
Southern Alberta, twenty miles from the rail- 
way and the nearest police detachment, had 
picked up the message and had telephoned it 
to the police detachment. 

GOOD DEEDS 

IN Edmonton Hospital the wife of a com- 
mercial traveler lay awaiting a serious oper- 
ation. Her husband was on his rounds, in 
small places where the ordinary means of find- 
ing him were useless. CJCA located the hus- 
band in a few hours, and he came into the 
city on a fast freight, in time to be at his wife's 
side during her time of trial. 

Soon will Arctic loneliness pioneer loneli- 
ness the loneliness of the remote farm home 
and the distant trapper's cabin be a thing of 
the past. Soon will Amokuk and his Eskimo 
friends, in their ice igloo on the Arctic shores, 
sooth and amuse their babies with radio stories 



A Canadian Broadcasting Station 



155 



from CJCA's childrens' hour, and Yellowknife, 
Dogrib, and Cree Indian, perhaps forgetting 
ancient feuds and barbaric dances, spend happy 
hours listening-in while CJCA amuses them 
with music and song, and all the news of the 
great world of the White Man, that lies beyond 
the doors of their forest wilderness. 

The Journal opened its first radio station 
May i, 1922, installing a Marconi Wireless 
Co. YC 3 type radiophone set, the normal input 
being 500 watts, and on a wavelength of 450 
meters, the antenna output was 3 amperes. 

JUST A BIT TECHNICAL 

THE transmitting gear consisted of trans- 
formed 100 volt A. C. to 6000 volts A. C., 
which was rectified on one side by. a rectifying 
tube, and a series of condensers employed to 
smooth out the fluctuations, and the resultant 
supplied the plate of the 5oo-watt valve. Grid 
modulation was the method used to modulate 
the output at voice frequencies. 

This set gave successful transmission as far 
as Tampa, Florida. A new station was installed 





MRS. THORNE 

Wife of the gallant police sergeant of the Arctic. Her 
favorite hobby is listening-in whenever she can get near 
a radio set which isn't often, since she is usually far up 
in the Arctic regions, where radio is considerable of a rarity 



SERGEANT THORNE 

Of the Royal Canadian Mounted Police, who is an en- 
thusiastic radio fan. He hopes to have radio installed 
this year at the police post at Herschel Island where he 
now is arranging details for the execution of two Eskimo 
murderers 

on April 23, 1923. The set is unique in the fact 
that none of the usual electrical machinery is 
used in its operation, the main source of electri- 
cal energy being supplied directly from the do- 
mestic 1 10 volt6ocycle lightingcircuit. Atrans- 
former supplies on the secondary side, 10,000 
volts, having a capacity rating of 3 K. V. A. 

CJCA's schedule, Mountain time, is as fol- 
lows: 

12:30 noon, reports. 
7:30 to 8 p. M. Childrens' half-hour. 
8:30 to 9:30 P. M. Evening concerts. 
11:15 p - M - Thursday nights. Igloo Hut 

meetings. 

Tuesday and Saturday nights at 10 p. M., 
calls to stations in the North West Terri- 
tories are given. 

(The Igloo Hut is the name of a radio club of 
clever and enthusiastic musicians, whose pro- 
grams are always received with delight by the 
fans.) 



Announcing Some Announcers 



WDAF 



WOAW 



WOS 



WWJ 



AT WOAW 

Is Gene Rouse, a genial announcer 

at this popular and well-known 

station 




AT W O S 

Is J. M. Witten, announcer and 

program director of this station in 

the capitol city of Missouri 



Underwood & Underwood 

AT WDAF 

Is Leon J. Fitzpatrick, who is chief 
announcer of the station, "Happy 
Lark" of the famous "Nighthawk 
Frolic", and radio editor of the 
Kansas City Star 




AT WWJ 

Is Edwin L. Tyson, whose measured, calm accents are a pleasant 
event in the lives of radio listeners throughout the Middle West 




A Word from the Enemy 

A Ship Operator Talks with and about His Friends the 
Broadcast Listeners and adds Some Constructive Suggestions 

By R. E. SHLUKBIER 



Commercial Radio Operator 



DURING the two long years the 
sailor member of the family had 
been gone, he had completely en- 
circled the globe in the capacity 
of radio operator on a tramp 
freighter. It was with some emotion, there- 
fore, that he rushed home and let himself in 
through the door. 

Things seemed strangely quiet inside but an 
entrancing odor from the kitchen reassured 
him. Dubiously he moved through the rooms 
to the kitchen where he stood speechless with 
wonder. There sat Grandma, all unconscious 
of his presence, or of anything else for that 
matter, a pair of phones clamped over her ears, 
darning socks. She was nodding her head in 
regular momentum, and were his eyes deceiv- 
ing him, or was just the slightest rhythmic 
motion of her shoulders perceptible? Sud- 
denly she was all attention, her hands moved 
deftly through a maze of cardboard tubes and 



a seemingly hopeless mixture of wires, and a 
half dozen knobs were given a slight adjust- 
ment. Then the contents of a pot on the stove 
was energetically stirred and the socks darned 
again double speed. 

"Grandma! What in the world " 

After the stormy greeting in which Mother 
joined from upstairs, came questions about the 
mysterious contraption. "Oh!" said Grand- 
ma, " Clare made it and you know they don't 
play many gramophone records any more. I 
was just listening to dance music played by 
Dan's Orchestra. You remember him don't 
you?" 

Afterwards the wanderer was given a rousing 
welcome by Dad and quite stampeded by his 
brother Clare, one of those indescribable 
American youths possessed of an insatiable 
curiosity. At dinner the conversation again 
swung to radio and it developed that the young- 
ster had a mania, not for radio lyric sopranos or 



158 



Radio Broadcast 



bedtime stories, but for long-distance reception. 
He completely confounded the family with a 
volley of technical terms, mildly amusing his 
brother, Dad, and Mother. Grandma openly 
worshipped. 

Looking askance at Dad whose dial twistings 
had produced no startling results, he claimed 
having received Pittsburgh and defiantly 
boasted that the new set he was going to build 
(when he got the money) would bring in the 
stations in the Middle West. 

HOW TIMES HAVE CHANGED 

SO TH I S was the result of giving that young 
upstart a few crystals and coils of wire two 

: years before to enable him to listen to an 
amateur who was at intervals broadcasting 
gramophone records. Slowly all the story was 
unfolded: A near-by station had started broad- 

i casting music regularly which greatly stimulated 
his interest. The young rascal stole or bor- 

; rowed every radio publication obtainable, tried 

1 every possible crystal combination, and by 
hoarding quarters exacted from Dad under var- 
ious pretexts and the regular half dollar from 
Mother on Saturday he finally got an audion. 
To the credit of his nimble mind be it said 
that Dad did not discover that filament current 
was necessary for the operation of the audion 
nor did he discover its source until an irate 
neighbor followed two wires from the battery 
of his Ford through the kitchen window to a 
table in a corner where Grandma zealously pre- 
served a hiding place for these works of iniquity. 
The Ford stood underneath an open lean-to 
close by and the neighbor seldom used it after 
he returned from work at night. Whether or 
not Grandma was entirely ignorant of the cir- 
cumstances was not determined but that the 
shadow of suspicion should fall upon her made 
no especial difference. Anyhow, the kitchen 
was her undisputed domain after supper and 
the rest of the family noted the youngster's 
doings only absently. Dad, now thoroughly 
alive to the gravity of the situation, let the 
taxes go by delinquent and purchased a storage 
battery. 

Clare could not have acquired his present 
knowledge without paying the price in the way 
of ruined tubes and materials. After a little 
questioning in private, he diffidently admitted 
that Grandma had been contributing her egg 
money. 

A few days later, materials for an up-to-date 
tuner and amplifier were purchased and the two 



brothers combined their experience in the de- 
signing of a receiver. Dad built the cabinet 
and after the first demonstration retracted 
entirely his prediction that he would not get 
any enjoyment out of a loud speaker. He had 
heard one of the screechy things somewhere 
down town. The music produced was mel- 
low and well modulated. Radio got a boost 
and the professional operator was awakened to 
the fact of its existence for a new purpose. 

When Clare's brother again went to sea, he 
listened for the music and was surprised to find 
how consistently he could hear the same voice 
and the same music heard by the folks at home. 
Even in the far-off Pacific on the way to the 
Orient he occasionally heard music from home. 

IN ONE SHORT YEAR 

ON NEARING the American coast on the 
return voyage, he was astonished to hear 
many new broadcasting stations. Stations in 
practically every state were heard. On his 
arrival home he found that long-distance recep- 
tion had become the regular thing and that 
Clare at times was picking up stations a thou- 
sand miles away with loud-speaker volume. 

However, they complained of code inter- 
ference. It seemed to be the fashion to blame 
this on the telegraph amateurs and so Clare 
berated them with zeal, backing up his charges 
with various magazine accounts of like inter- 
ference. It was amusing to read these obvi- 
ously inaccurate accounts and the occasional 
replies from the amateurs who countered with 
insidious remarks about non-selective re- 
ceivers, if indeed they were not too busy to say 
anything at all. 

Clare tuned-in a station and his brother 
found that the chief offender was a powerful 
commercial station a few miles away whose 
broad spark could not be tuned out at that dis- 
tance even though the receiver was unusually 
selective. These interfering signals from this 
busy station were so continuous that the con- 
certs were practically demoralized and Dad had 
lost interest altogether. A Navy station also 
contributed some disturbance but the amateurs 
who seemed to have sharply tuned transmitting 
apparatus were seldom heard even though a 
few rotary spark notes and a few key thumps 
seeped through. They tried wave traps and 
directional antennas, with but mediocre success. 

After another interval, of a few months the 
commercial and Navy stations installed tube 
sets which left the local concerts undisturbed. 



A Word from the Enemy 



159 



On the other hand, broadcasting wavelengths 
had been changed, ] the individual receiver's 
range increased by the addition of radio- 
frequency amplifiers and code interference was 
worse than ever when one tried to receive out- 
side stations. It was also noted that the long- 
suffering amateur was no longer abused and 
that the wrath of the irate fans was transferred 
to the unsuspecting commercial operator, 
whose broad waves overlapped the broadcasting 
when he used his 45O-meter wave. Publications 
were beginning to say things about ship-to-shore 
communication and government officials were 
complaining about not having sufficient funds 
to cope with the situation. 

THE PROBLEM OF CODE INTERFERENCE 

SINCE the writer at times probably con- 
tributes to this interference he will suggest 
a few of the 
conditions con- 
fronting the 
commerical op' 
erator at sea. 

Many ships 
have been furn- 
ished with con- 
tinuous wave 
transmitters 
working on a 
wavelength of 
2,400 meters 
with the object 
of relieving the 
congestion on 
600 meters and 
incidentally to 
increase their 
working range. 
Changing conditions of the past WHERE THE 



five years, however, have more 
than defeated the purpose. 
The shore transmitters have been tremendously 
improved and the receivers on board ship are 
now very sensitive. New commercial shore 
stations on the east coast can be heard the length 
and breadth of the Atlantic and they communi- 
cate directly with ships as far east as Gib- 
raltar and west for hundreds of miles into the 
Pacific. 

It is not easy to communicate over long dis- 
tances successfully through this 6oo-meter con- 
fusion, and so wavelengths not so crowded are 
resorted to. A 7o6-meter wave was assigned 
but it is too close to the 6oo-meter wave and to 



the 8oo-meter compass station wave to be en- 
tirely practical and so the 45O-meter wave which 
is giving the music listeners all the interference, 
is used. This wave cannot be used during most 
of the broadcasting hours of the local stations, 
but it is doubtful that the signals of a distant 
ship are very noticeable through the loud sig- 
nals of a local broadcasting station and so the 
listener is still annoyed when he tries to get a 
little thrill out of midnight DX reception. 

While a fan is patiently turning his dials in 
search of China, a host of ship operators are also 
trying to get DX, and this is not nearly as easy 
as is generally supposed. It often happens 
that when a wireless operator tells about com- 
municating directly with his home port several 
thousand miles away, the listener will not be 
impressed. In fact, the idea among the unin- 
itiated seems to be that, consistent with the 

other wonders 
of the century, 
one must but 
press the key to 
6id dreamy 
Honolulu a 
fond good- 
night or to as- 
certain via 
Hamburg,the 
status of good 
German sau- 
sages. 

Desirable 
as this condi- 
tion may be, 
it is not as yet 
realized and the 
operator is still 
apt to be in- 
ENEMY LURKS gloriously balked by a paltry 




A corner in radio on a cargo ship few hundred miles and send 

his dots and dashes with a 
persistency born of desperation as an angry 
captain moves heaven and earth in his insist- 
ence to dispatch this message or that. 

THE SHIP OPERATOR HAS HIS TROUBLES 

OVER a distance of a few hundred miles, 
communication is very easy, but beyond 
that, especially on runs through the tropics, 
static will sometimes demoralize communica- 
tion altogether even over short distances. Be- 
sides there is the ever-present and obnoxious 
problem of interference. Interference is be- 
coming more and more serious because of the 



i6o 



Radio Broadcast 



increased working ranges the ship operators 
are expected to cover. 

Last winter, ships occasionally managed to 
get their signals through to New York from the 
Pacific, and this season it is being done nightly. 
A station will not as a rule respond the first 
time it is called since any number of ships 
within several thousand miles may be calling 
it, and so the air is crowded with a steady re- 
petition of the same signals until the desired 




IN THE PANAMA CANAL 
Mr. Shlukbier's ship in a quiet moment 

station is either raised or daylight overtakes the 
ship, putting an end to DX work until night 
falls again. 

Since passenger ships are equipped with con- 
tinuous wave transmitters taking the load of 
love and kiss messages from the 6oo-meter 
wave, and cannot therefore disturb the broad- 
cast listener, someone may wonder why a 
freighter so far away should wish to get in 



touch with the home port and whether or not 
all this interference is necessary. That is 
exactly what all operators worthy of the name 
are asking themselves. 

A BAS T R REPORTS 

IT IS safe to say that over half of the signals 
are caused by unpaid position messages 
known as T R reports. Their primary object 
was to notify a shore station that a certain ship 
was within range. These reports have de- 
generated into a general contest for reaching 
either New York or San Francisco according to 
the location of the ship. It is true that these 
reports are printed by newspapers in some sec- 
tions of the country. These reports should 
only be sent through the normal ranges of a 
coast station, or better still, daylight range, and 
a ban should be put on their transmission at 
night. This would be more effective in reduc- 
ing the amount of interference than all the 
tube sets which could be installed for years 
to come. 

There are also other violations of radio oper- 
ating regulations which cause needless inter- 
ference. The government officials rely almost 
entirely upon the operators themselves to re- 
port these. It is quite characteristic of the 
American operator to assume a tolerant atti- 
tude, and actually very few reports are forth- 
coming. A possible remedy would be to ap- 
point certain ships with reliable operators as 
traffic ships giving them authority to stop 
unnecessary signals. They would be supplied 
with official cards to be sent to offenders warn- 
ing them that a second offense would be made 
the subject of an official report. 

Reduction of interference would also increase 
the reliability of radio for the protection of 
lives at sea which is its ultimate reason for exis- 
tence. At present a ship in distress forced to 
use a low-powered emergency set would prob- 
ably not be heard at all unless by some ship 
very close by. This situation may explain 
some of the mysteries of the deep. Moreover 
it often happens that an operator has an im- 
portant message and is unable to put it through 
on account of unimportant traffic which is 
causing this external interference. 

The broadcast listener can be assured that in 
time all code signals will disappear from the 
broadcast wavelength, although a certain 
amount of it will be encountered for some time. 
Meanwhile this disturbance should be re- 
garded with tolerance. 



^ROADCASTINQ 

Contest Opened by T(ADIO BROADCAST 

in which a prize of $500 is offered 



What We Want 

A workable plan which shall take into account the problems in present radio 
broadcasting and propose a practical solution. How, for example, are the restrictions 
now imposed by the music copyright law to be adjusted to the peculiar conditions of 
broadcasting? How is the complex radio patent situation to be unsnarled so that 
broadcasting may develop? Should broadcasting stations be allowed to advertise? 

These are some of the questions involved and subjects which must receive careful 
attention in an intelligent answer to the problem which is the title of this contest. 

It Is To Be T>one 



The plan must not be more than 1500 words long. It must be double-spaced and 
typewritten, and must be prefaced with a concise summary. The plan must be in the 
mails not later than July 20, 1924, and must be addressed, RADIO BROADCAST Who Is 
to Pay Contest, care American Radio Association, 50 Union Square, New York City. 

The contest is open absolutely to every one, except employees of RADIO BROADCAST 
and officials of the American Radio Association. A contestant may submit more 
than one plan. If the winning plan is received from two different sources, the judges 
will award the prize to the contestant whose plan was mailed first. 

Judges 

Will be shortly announced and will be men well-known in radio and public affairs. 
What Information You ^feed 

There are several sources from which the contestant can secure information, in case 
he does not already know certain of the facts. Among these are the National Associa- 
tion of Broadcasters, 1265 Broadway, New York City; the American Radio Association, 
50 Union Square, New York, the Radio Broadcaster's Society of America, care George 
Schubel, secretary, 154 Nassau Street, New York, the American Society of Composers 
and Authors, the Westinghouse Electric and Manufacturing Company, the Radio Cor- 
poration of America, the General Electric Company, and the various manufacturers, 
and broadcasting stations. 



The independent committee of judges will award the prize of $500 to the plan which 
in their judgment is most workable and practical, and which follows the rules given 
above. No other prizes will be given. 

No questions regarding the contest can be answered by RADIO BROADCAST by mail. 




THE TELEDYNE 



Rear view of a completed commercial receiver. The home constructor by using good parts 
which he may select himself and mount on a panel as suits him best, can easily build this set 



How to Build a Teledyne Radio 

Receiver 

By BOWDEN WASHINGTON 

Chief Engineer, Cutting & Washington Radio Corp., and designer of the Teledyne 

In RADIO BROADCAST for May Mr. Washington in "Regeneration Without the Squeal" 
described the commercial form of the receiver which he has designed to get volume and 
distance without unneighborly radiation. This is his how-to-build-it article on that 
receiver. THE EDITOR. 






i HE principle of regeneration is un- 
doubtedly of great value inasmuch 
as regeneration increases the useful- 
ness of a vacuum tube up to perhaps 
a hundred times. On the other 
hand, regeneration as applied to the conven- 
tional type of single-circuit broadcast receiver 
(and to a lesser degree to the two-circuit type), 
becomes a menace to the whole future of home 
radio. This, of course, is on account of the 
possibility of these receivers transmiting, 
"re-radiating" as it is incorrectly called, though 
it is not the re-radiation but merely simple 
radiation which causes most of the trouble. 
As any one who lives in a town of any size 



knows, the interference created by these re- 
ceivers has practically ruined distant reception. 

It seems, however, unwise to discard this 
highly useful and quite economical method of 
sensitizing a tube, and in a search for a regen- 
erative receiver which would not create inter- 
ference, the Teledyne was developed. 

This receiver consists of a tuned radio- 
frequency amplifier, which is entirely stable 
and shows no tendency to oscillate, a fully 
regenerative detector, and the usual two audio- 
frequency stages. With four UV-igg tubes, 
used in conjunction with a hundred-foot, single- 
wire antenna, it is possible to obtain loud 
speaker signals on fairly distant stations. 



How to Build a Teledyne Radio Receiver 



In comparative tests against a five-tube neu- 
trodyne, I have found that this circuit gives 
considerably more volume. It is also highly 
selective, and extremely easy to tune. The 
detector may be set into oscillation and the 
"carrier wave whistle" picked up without fear 
of creating any appreciable outside interference. 

The radio-frequency amplifier operates in 
approximately the following manner: 

Its grid inductance is also the antenna tuning 
inductance. Its plate inductance forms a de- 
livery coil and transfers its output energy to 
the detector grid inductance, which is tuned by 
the usual parallel variable condenser. The 
output of a vacuum tube (somewhat like a dry 
cell) is greatest when the external impedence of 
the output circuit is equal to the internal im- 
pedence of the output side of the tube. By 
properly proportioning the inductance and 
coupling of the delivery coil, the impedence of 
the detector grid circuit may be made to 
"show through" into the amplifier plate cir- 
cuit at this correct impedence value when the 
detector grid circuit is tuned. 

THE CONSTRUCTOR HAS PLENTY OF LEEWAY 

IN GIVING directions as to the construction 
of the Teledyne, I have purposely omitted 
any detailed panel drilling layout, but have 



E 8 



shown instead the correct layout of the various 
parts. My reason for this is that I do not wish 
to recommend any particular makes of parts; 
a particular make may not always be available, 
and the constructor may have at hand certain 
perfectly appropriate parts of a make other 
than that specified, which he would be justified 
in using rather than purchasing new ones. 
Good parts, of course, should be used. It is 
important to keep the radio-frequency layout 
approximately as shown, as it is absolutely es- 
sential that no coupling shall exist between the 
two grid inductances. This means that the 
radio-frequency grid inductance should be 
mounted at some little distance from the de- 
tector grid inductance and horizontally. The 
detector grid inductance should be mounted 
vertically, and in such a position that an ex- 
tension of the axis of the radio-frequency coil 
would pass through the middle turn of the de- 
tector grid winding, and at the same time in- 
tercept the axis of this coil. 

The arrangement of the audio amplifier is of 
course optional with the builder, though some 
simple shock absorber mount such as that in- 
dicated should be devised for the detector and 
the two audio amplifier tubes. As all four 
tubes will be used at all times except for local 
reception, but one rheostat is shown for sim- 



n n n 




FIG. I 
Plan view 



164 



Radio Broadcast 




FIG. 2 

Right Elevation 

plicity, and a two-point switch is provided, so 
that the loud speaker may be operated on one or 
two audio stages. 

These are the necessary parts of the complete 
Teledyne as shown: 

i panel 2" x i|" x ^" 
i panel 6" x 2\" x T 3 S " 
i panel 19$" x 6J" x ft" 

1 wooden base board, preferably laminated 195" x 10" 
x \" 

2 good variable condensers .ooo25-.ooo3 micro farads. 

3 3!" dials. 

2 Instrument type switches with bushings. 

4 switch points. 
4 switch stops. 

i pc. tubing 4" outside diameter, z\" long, fa" 

wall 
i pc. tubing 4" outside diameter, 3j" long, T V 

wall. 

1 pc. tubing 35" outside diameter, f" long, fa" 
wall. 

4 good sockets for UV-iox) tubes. 

2 audio transformers. 

Seven to 12 ohm rheostat with "off" position and knob. 

good .00025 m fd. mica grid condenser. 

3-megohm leak. 

good .002 mfd. mica condenser. 

paper telephone condenser of any capacity above .04 



mfd. (This condenser is at all times 
across the B battery, and if leaky will 
run this battery down. To test for 
leaks place the condenser across 90 volt 
B battery, remove it, wait several min- 
utes and discharge the condenser with a 
piece of metal. A quite noticeable spark 
will occur if the condenser is faultless). 

1 1 binding posts. 

150 ft. No. 26 D. S. C. wire (double silk 
covered) 

10 ft. No. 30 D. S. C. wire (double silk 
covered) 

i 3-point jack. 

Miscellaneous wood and machine screws, 
strip brass, regeneration coil shaft, flexi- 
ble pigtail material for regeneration coil 
and tube mount leads, phosphor bronze 
strip /',/' x 26 gauge for shock absorber 
spring, etc. 

BUILDING THE TELEDYNE 

1 WOULD rather leave the exact details to the 
individual constructor for very much the 
same reason that 1 do not wish to specify makes 
of parts. 1 believe the average person who has 
arrived at the stage of building his own four 
tube set usually has a fair accumulation of odds 
and ends, some of which certainly can be used. 
A suggested layout is shown in Fig. i. The 
radio-frequency grid inductance is shown at the 
left, supported from the panel by separators 
which may be cut out of brass tubing with a 
hack saw, and this coil may also be fastened to 
the base with two wood screws at its point of 
tangency. Mounted on the panel in front of 
it will be seen a two-point switch which in- 
cludes either 50 or 80 turns in the antenna cir- 
cuit. This is necessary to cover the entire 
broadcast wavelength band on all sizes of 
antennas. Next is the antenna tuning con- 
denser, followed by the detector tuning con- 
denser. The jack shown is of the "three- 
point" type. Loud speaker binding posts are 













DITKTOR TUNE 











FIG. 3 

Front elevation 



How to Build a Teledyne Radio Receiver 



165 



provided on the rear terminal board, and the 
jack is so wired that when the telephone plug 
is removed, the loud speaker is automatically 
cut in. This is rather a nice arrangement, as 
it enables the user to "fish" for distance and 
get the tuning done on his telephones, and then 
by merely pulling the plug half way out, flood 
the room with music from a distant station. 

Next comes the detector grid inductance 
mounted vertically with the detector regenera- 
tion coil. The rheostat, B battery condenser, and 
one two-stage switch are at the extreme right. 

I have shown the detector and two audio 
tubes mounted on a strip of bakelite or wood 
and sprung from the base by four U shaped 
phosphor bronze strips. It is suggested that a 
straight wire be run along the filament con- 
nections on the sockets and that two of these 
spring supports be used to carry the filament 
current. There is no need of a vibration-proof 
mounting on the radio frequency tube. 

It is convenient to use the right hand socket 
on the strip for the detector tube, the middle 
socket for first, and the left for second audio 
frequency stage. 

The small terminal board at the left contains 
the antenna and ground binding posts. The 
larger board at the right carries plus A,- A,- B, 
plus 22^, plus 90, plus C,- C and two posts for 
the loud speaker. 



All winding of the coils should be done ex- 
actly as shown in Fig. 4. Notice that a strip of 
well shellacked cardboard ^Y' thick is laid 
over the detector grid inductance at the fila- 
ment end before the four-turn delivery coil is 
wound in place. Note also that this delivery 
coil begins over the first turn of the detector 
winding. 

All wiring should be made as short and direct 
as possible, and all joints soldered with resin 
cored solder. Do not use either paste or 
acid. 

Fig. 5 shows the connections of a Teledyne. 

TUNING THE RECEIVER 

THE Teledyne is extremely simple to tune, 
but of course requires some practice. 
Real volume on long distance is only usually ob- 
tained by a final readjustment all around. A 
vernier is not necessary, and for that reason I 
have not shown it, but a vernier on the detector 
tuning condenser, either mechanical or elec- 
trical, is undoubtedly an aid to making the 
final adjustment. 

There are two general methods of tuning the 
Teledyne, the first is the familiar beat note 
methods whereby the detector is made to 
oscillate by increasing the regeneration control. 
The secondary or grid circuit tuning adjust- 
ment is then varied, and the various beat-notes 




-F 



[KB 



FIG. 4 
Detector grid coil, R. F. plate coil and regeneration coil 



i66 



Radio Broadcast 



of the stations broadcasting will be heard. 
One of these is chosen, and the antenna circuit 
is then tuned to this wave by varying the an- 
tenna series condenser until the beat-note is 
loudest. The regeneration is then reduced 
until the beat-note disappears, and the received 
program is clear. 

The second method of tuning is similar to 
that employed with the neutrodyne type of re- 
ceiver, with the exception that only two con- 
trols are necessary. The regeneration is re- 
duced to a low value, and the antenna and grid 
circuit tuning adjustments are then simultane- 
ously varied, and held in tune with each other 
as the entire scale is covered. The process is 
exactly similar to that of tuning the neutro- 
dyne, except that it is much more rapid. 

The tuning adjustments are almost entirely 
independent of each other, so it is readily pos- 
sible to record the dial settings of the antenna 
and grid tuning adjustments for every station 
heard, and thus keep a permanent record of 
these stations. By reference to this record 
the dials may then be set for any particular 
station, at any time, and that station will be 
received without the necessity of retuning. 

THE ANTENNA 

THE antenna used depends largely on the 
location of the receiver. Like most re- 
ceivers, it is somewhat more selective on a 



short antenna. If located within five miles of 
a large broadcasting station, I would recom- 
mend a single wire, with an overall length from 
the receiver to the far end of 65 ft. ; if located 
at a greater distance from a powerful trans- 
mitter, lengths up to 1 50 ft. may be used. The 
best available ground should be used, usually a 
good, clean connection to a cold water pipe. 
Sandpaper both the inside of the ground clamp 
and the pipe. 

One word of warning never burn the fila- 
ments of UV-I99 tubes hotter than is abso- 
lutely necessary for good reception. Burning 
them too hot does not increase their response, 
but does boil the thorium off the filaments, and 
this in a short time ruins the tube. This is 
sometimes rather disconcerting, as the tube, of 
course, lights and appears normal, but it is 
either feeble or totally inoperative. There is 
no need of this happening however, if the above 
precaution is taken. 

The Teledyne can be used quite successfully 
even on distance, with a ten foot indoor an- 
tenna, though the results are naturally not as 
good as if an outdoor antenna is used. 

On a ten foot wire running from the set to the 
picture molding, the writer has received ade- 
quate loud speaker signals in Minneapolis from 
Omaha, Chicago, St. Louis, Davenport, Cleve- 
land, and Pittsburgh. 

It must be remembered that there are oc- 



o 





FIG. 5 
R. F. grid coil 



How to Build a Teledyne Radio Receiver 



167 




FIG. 6 

Complete diagram of connections of the circuit 



casional buildings which owing to the large 
amount of metal used in their construction act 
as a shield, in which case an indoor antenna is 
not satisfactory. 

In using a short indoor antenna connect as 
follows: 

i. Connect the ground lead in the usual 
manner. 



Connect a fixed mica condenser of 125 
micro-micro-farads capacity between the 
antenna and ground binding posts. This 
size is sometimes difficult to obtain. 
Two 250 mmfd. Dubilier grid con- 
densers may be used in series. 

Connect the ten foot antenna directly to 
the grid of the radio-frequency tube. 



the farmer gets out of broadcasting is the subject of an interesting 
article by Robert H. Moulton which will appear in RADIO BROADCAST 
for July. Mr. Moulton tells how the farmer gets something out of the air be- 
sides music and bow bis radio receiver is paying him dividends. 



The Uses of the Three-Electrode Tube 

WHAT MAKES THE WHEELS GO 'ROUND: IV 
By WALTER VAN B. ROBERTS 



Readers who wish to have available a fund of reliable radio theory more up to date than most textbooks 
will do well to keep this series of articles by Mr. Roberts. All of these articles, while treating of the general 
subject of radio theory, are complete in themselves and each installment is comprehensible alone. This is 
the fourth of the series which began in this magazine for March. THE EDITOR. 



r \\\E 

in i 

con 

and 

^^ /*in 



three-electrode tube can be used 
in a great many ways, but its use in 
connection with radio transmission 
and reception is confined almost ex- 
clusively to the following: 

1. Modulation, or the process of varying the 
amplitude of the transmitted radio waves in 
accordance with the variations of air pressure 
that constitute the voice or music. 

2. Demodulation (also called rectification 
and detection) or the process of converting 
modulated radio-frequency alternating cur- 




FIG. 14 

How an unmodulated continuous 
radio wave may be diagrammed 

rents into direct current varying in strength 
in accordance with the original voice or music. 

3. Regeneration, a process for neutralizing 
some of the unavoidable resistance in the re- 
ceiving circuits, resulting in greater currents 
being produced by the incoming waves. 

4. Amplification, or increasing the energy 
of either radio- or audio- (voice or music) fre- 
quency currents, without changing their form. 

5. Oscillation, or the production of high 
frequency alternating currents. At the trans- 
mitting stations it is high frequency current 
flowing in the antenna that radiates energy 
under the name of wireless or radio waves. 



37. MODULATION 

THE simplest case of modulation occurs 
when a pure note of a single frequency, such 
as produced by a tuning fork, is transmitted. 
When no sound is supplied to the transmitter 
or microphone the transmitting station is send- 
ing out radio waves of a single frequency and 
constant amplitude as shown in Fig. 14. But 
if an air wave or variations of air pressure from 
a vibrating tuning fork hit the microphone as 
shown in Fig. 15 then the modulating ap- 
paratus causes the amplitude of the radio 
waves to vary in accordance with the tuning 
fork wave. If the original radio wave be rep- 
resented by sin pt and the air wave from the 
tuning fork by sin qt then the modulated radio 
wave would be of the form sin pt (i+m sin qt) 
where the constant m shows the degree of 
modulation, that is, how large a percentage 
change in the amplitude of the original radio 
wave is caused by the modulation, (if m=o 
the wave would not be modulated at all. If 
m = i the amplitude would periodically fall to 
zero as shown in Fig. 16.) 

38. ANALYSIS OF MODULATED WAVES* 

NOW the surprising part about the modu- 
lated wave is that it can no longer be con- 
sidered to have a single frequency. For by a 
simple trigonometric formula we can show 

that sin pt ( i + m sin qt) = sin pt+ m sin (p+ q)t 

2 

+ sin (p q)t which shows that the modu- 

2 

lated waves must be treated as the sum of 
three different trains of constant amplitude 



"The starred sections may be omitted on the first read- 
ing, since these parts are rather more technical than the 
main part of the series. 



The Uses of the Three-Electrode Tube 



169 




FIG. 15 

A continuous radio wave modulated by an 
audio-frequency impulse from the tuning fork 

waves of frequencies respectively: i, the same 
as the frequency of the original unmodulated 
radio wave, which is called the "carrier" 
frequency; 2, a frequency greater than that of 
the carrier by the signal frequency; and, 3, 
a frequency less than the carrier by the same 
amount. That is, the carrier frequency being 

P Q 

^ and the modulating frequency ~^~, then 
there will be sent out waves of frequencies 

2X' 2X ' 2TU' 2TC 2Tl' 

39. SIDE BANDS* 

FOR very high quality music all tones be- 
tween about 30 and 5000 vibrations per 
second should be transmitted with equal ef- 
ficiency. To transmit the former we must, as 
explained above, transmit a frequency 30 cycles 
greater than the carrier and another 30 cycles 
less than the carrier, in addition to the carrier 
itself. To transmit the 5000 we must use the 
frequencies 5000 greater and 5000 less than 
the carrier. And to transmit all the inter- 
mediate tones, we must use the two bands of 
frequencies (called the upper and lower side 
bands) shown shaded in Fig. 17. 

The whole range of frequencies used is called 
a "channel." In the case just described the 
width of the channel is 10,000 cycles. The 
important thing about all this is that broad- 
casting stations do not use only a single fre- 
quency or wavelength as might be supposed 
from the figure given in the newspaper radio 
programs (that figure is the frequency of their 





carrier wave in kilocycles per second) but they 
each require a channel of definite width, and 
hence only a rather small number can work at 
once without their channels overlapping, which 
results, from the listener's point of view, in a 
continuous whistling sound (of high pitch if 
the channels overlap only slightly, and of 
lower pitch if the overlapping is greater). 

40. RELATION OF FREQUENCY TO WAVELENGTH 

RADIO waves travel with the speed of 
light, 300,000,000 meters per second. 
Now in any wave motion the frequency or 
number of waves passing a given point per 
second, multiplied by the wavelength, gives 
the speed with which the waves are traveling. 
If a train of railroad cars passes a given point 
at the rate of two cars per second and each car 
is fifty feet long, the speed of the train is ob- 
viously one hundred feet per second. Quite 
similarly, if the frequency of passing radio 




FIG. 1 6 



FIG. 17 

The complex emitted wave is composed of a carrier fre- 
quency and two side bands. The whole is a "channel" 

waves is one million per second, then the 
length of each wave must be 300 meters to 
make the speed come out the value stated 
above. For a long time the term wavelength 
has been used rather than frequency, but at 
present the kilocycles seem to be displacing the 
meters. The reason for this is that if the fre- 
quencies of several transmitting stations are 
given, we need only make sure that no two 
are within about ten kilocycles of each other in 
order to be sure that they will not interfere. 
(Non-interference when waves are only ten 
kilocycles apart will of course only be true if 
a very highly selective receiving set is used, one 
that can pick up all the frequencies lying in 
one channel and none lying outside of it). 
On the other hand, if we work with wave- 
lengths, we must calculate anew the width of 
channel expressed in meters for every different 
wavelength. Thus a lo-kilocycle channel at 
three hundred meters wavelength is only a 
three meter channel, while at three thousand 
meters wavelength, it is a three hundred meter 



170 



Radio Broadcast 



channel. There are about nine times as many 
ten kilocycle channels available between the 
wavelengths 30 and 300 meters as there are 
between 300 meters and 30,000. 

41. MATHEMATICS OF A MODULATING AMPLI- 
FIER TUBE* 

FIG. 1 8 shows how a vacuum tube can be 
made to modulate. The grid is supplied 
by means of transformers with the carrier 
frequency and the modulating frequency. We 
now make use of the equation given previously 
for plate current, putting in the two alternating 
potentials along with the C battery potential. 
i p = K (B+[xX .grid potential) 2 = K (B+|x[C 
+ a sin qt + b sin pt]) 2 

= K [(B + (xC) -f- (x (a sin qt + b sin pt)] 2 
= K (B + [xCJ 2 which is direct current 
+2K (B + (jiC) (a sin qt + b sin pt) [x 
which are currents of frequencies Q/2ic and 

P/2TC 

+ K [x 2 a 2 sin 2 qt which reduces to direct 
current and current of frequency 2 Q/2iu 
+ K {x 2 b 2 sin 2 pt which reduces to direct 
current and current of frequency 2 p/2x 
-f- 2K[x 2 ab sin qt sin pt which can be re- 

P O 

solved into currents of frequencies ^ and 
P+Q 

2X. 

Now of all three currents, only those of fre- 

, P+Q , P-Q 
quencies p/2x, ^ , and ^ are near enough 

"in tune" with the antenna circuit to pro- 
duce appreciable currents in it. Hence the 
antenna current and the radio waves caused 
by it, have the carrier frequency and the 
two side frequencies, and hence correspond to 
the modulated waves analysed in a previous 
paragraph. 



RM)10 FREQUENCY SUPPLY 



THIS SUPPLIES THE GRID WITH 
THE LOW FREQUENCY VOLT WE 





-c 



FIG. l8 
A simple method of modulating a vacuum tube 



FIG. 19 

A commoner method of vacuum tube modulation 



42. THE HEISING SYSTEM OF MODULATION* 

THE modulating circuit of Fig. 18 is not one 
commonly used : it was chosen because the 
mathematics of its operation is easily worked 
out from the equation for plate current. The 
circuit most commonly used is shown in Fig. 19. 
Two tubes are used. The one not shown in the 
diagram is the oscillator that supplies the an- 
tenna with radio-frequency current. The cur- 
rent supply for the plates of both tubes comes 
through the iron core inductance or "chokfe" 
coil which tends to keep the total current sup- 
plied to both tubes constant. But the voice 
hitting the microphone causes voice-frequency 
variations of current in the primary of the 
transformer which in turn produce voice- 
frequency variations of the grid potential of 
the tube shown in the diagram. These varia- 
tions of grid potential cause the tube to draw 
a varying amount of plate current. But since 
the total current supply is kept constant, the 
oscillator tube must receive more whenever 
the other tube receives less and vice-versa. 
The more current the oscillator tube receives 
the more strongly it oscillates, while if it re- 

ceives less current than normal, its 

V7 oscillations are weakened. Thus, 
\1/ corresponding to the voice, we have 
variations in the radio wave ampli- 
tude, in other words the radiated 
wave is modulated by the voice. It 
might seem inefficient to use two 
tubes this way instead of one, but it 
is not so bad as it seems, for the 
oscillator by this method is part of 
the time being forced well above its 
allowable safe continuous output. 
This is the Heising system of modu- 
lation, and it is used in many 
of the most successful broadcasting 
stations. 



The Uses of the Three-Electrode Tube 



171 



43. SUPPRESSED CARRIER TRANSMISSION 

THE carrier wave has no part in conveying 
intelligence. It is required only for the 
purpose of demodulation at the receiving end. 
It can be left out entirely provided that a local 
oscillator tube is used at the receiving end to 
supply current of the same frequency to take 
its place. The " balanced modula- 
tor" used to get rid of the carrier 
is shown in Fig. 20. Analysis of 
this circuit (which is merely two 
tubes, each acting in the manner 
previously taken up) shows that the 
two side bands generated by each 
tube act additively in producing 
current in the antenna, but the 
carrier frequency current in the 
plate circuit of one tube just can- 
cels the effect of the carrier current 
in the other tube as far as produc- 
ing current in the antenna is con- 
cerned. Much power is wasted 
transmitting the carrier, but for 
most purposes it is best to do so 
because it is difficult to make the 
local oscillator at the receiving sta- 
tion supply just exactly the same 
frequency. Another advantage in suppressing 
the carrier is that the locally generated carrier 
frequency at the receiving end is not subject 
to variations in strength and hence there is a 
reduction in the amount of "fading" of the 
received signals. 

44. SINGLE SIDE BAND TRANSMISSION 

FURTHERMORE, only one of the side 
bands is required to convey the speech or 
music, as will be evident from the complete 
analysis of demodulation given later on. If 



only be one half as wide, which is an important 
feature if the ether is "crowded" with trans- 
mitting stations. Also, the receiving set can 
be made to receive only one half as wide a 
band of frequencies and hence offers only one 
half as much chance for static and other inter- 
ference to get in. If both the carrier and one 
side band are suppressed, the local oscillator at 



RADIO FREWENCX SUPPU 




only one is used, the channel required will carrier frequency. 



FIG. 20 

A "balanced modulator" system which eliminates the carrier wave 



the receiving end can be as much as fifty cycles 
different in frequency from the original carrier 
without serious interference with intelligibility 
of speech. However, the harmonic ratios in 
music would suffer. For the reasons men- 
tioned above the American Telephone and 
Telegraph Co. are using single side band trans- 
mission in their transatlantic telephony tests. 
This system is not now practicable for short 
wave work as it is too hard to "filter out" the 
side band that is not wanted, when the width 
of these bands is only a small fraction of the 




THE SUPER-HETERODYNE 

MAJOR EDWIN H. ARMSTRONG is writing his own story of 
his new super*- heterodyne, exactly as he described it before a 
recent meeting of the Radio Club of America, exclusively for RADIO 
BROADCAST. The article will appear in July. 

The super-heterodyne, one of the few new circuits brought out in 
recent years, was developed by Major Armstrong in France under 
war 'time pressure and now is becoming constantly more popular. 




What Our Readers 
Write Us 




Contra Women Announcers 

AT THE risk of opening an argument which 
might become somewhat unchivalrous, 
we are printing the letter which follows. It 
was written by a producer and distributor of 
phonograph records who has every qualifi- 
cation to know whereof he speaks. And, as a 
matter of fact, there is apparently no danger 
of the broadcast announcing profession sud- 
denly, or, indeed, even gradually being monopo- 
lized by women, for at present there are prob- 
ably not more than ten women announcers 
throughout the country. (This for those who 
may grow disturbed over the prospect not an 
editorial opinion). 

Editor, RADIO BROADCAST 
Doubleday, Page & Co., 
Garden City, L. I. 
DEAR SIR: 

The phonograph industry has learned much from radio 
of late. But broadcasting stations can learn some funda- 



,/TnTro. ,.B Doara also ae- 

i prlvpd fouiV^wW drivers of their 
licenses to operate. Two operators 
lost their permits because of alleged 




There were three JuT> m(sand > 
fourth was started before court ad-, 
Journed. 



SPEAKING ABOUT 



-RADIO- 

Have You Read the Article in Radio Broadcast for 
March Entitled 

TheTruth aboutTrick Circuits? 
Buy It and Read It 

NOTE I Didn't Write It and I'm Paying for This 
Advertisement? 

Allan T. Hanscom 



"SERVICE IN RADIO" 



from The Woonsocket(RI) Coll- Teh 6, l$2.4 

WHAT OUR READERS WRITE FOR US 
This two-column advertisement was inserted and 
paid for by an enthusiastic reader in Rhode Island 



mentals from our experience with the sales of phonograph 
records. 

When the speaker is not seen in person, and if that 
speaker be a woman, her voice is very undesirable, and to 
many, both men and women, displeasing. I submit this 
not as an argument, but as a fact. We have found that 
a record of a woman's talking voice will not sell, and it has 
cost several manufacturers several thousands of dollars to 
learn that despite the greatness of the artist, people will 
not pay good money to listen to the talking record of a 
woman's voice. Consequently, I believe that a vote of 
radio fans would show great disapproval of women an- 
nouncers and speakers. 

THIS letter is one of a considerable 
number of similar ones which have 
arrived since we published A. F. Van Dyck's 
two articles on " Man-Made Static" in the April 
and May numbers. , 

Editor, RADIO BROADCAST 
Doubleday, Page & Co., 
Garden City, L. I. 
DEAR SIR: 

Perhaps it might interest you to know that your article 
in April on "Man-Made Static" describing the trouble 
caused by an electric heating pad enabled me to discover 
the cause of a disturbance which had been causing me hours 
of profanity for over a year. Exactly the same situation 
as Mr. Van Dyck described had been happening in my 
house and I had been blaming everything and every one 
in the vicinity except the offending pad. 

Fifteen minutes after reading the article in RADIO BROAD- 
CAST, I had found the trouble. Of all the excruciating noises 
which bother the radio fan, this one caused by heating pads 
is the worst: it fairly sets one's teeth on edge. Compared 
with it, static of the worst kind and regenerative noises 
sound like the sweetest music. That was certainly a most 
profitable investment of twenty-five cents. 

ERNEST F. Dow 

LETTERS are still coming in, inspired by 
Carl Dreher's two recent articles on "Is 
the Broadcast Listener at Fault?" and " Is the 
Amateur at Fault?" There is, of course, 
much to be said on both sides, and only by the 
honest saying of it can the situation be clarified. 

Editor, RADIO BROADCAST 
Doubleday, Page & Co., 
Garden City, L. I. 
DEAR SIR: 

Carl Dreher's recent article on "Is the Broadcast 
Listener at Fault?" interested me, but I should like to 
make a few additional observations. 

The case of 9 RR, who is the gentleman referred to by 
Mr. Dreher as expressing sweet sympathy with the mid- 
night broadcasters can best be understood by remembering 
that he lives in the same city as the " Kansas City Night- 
hawks." When 9 RR keeps quiet from 8 until 10:30 P. M. 
in compliance with the law, and then is kept off for another 



RADIO BROADCAST ADVERTISER 



nnoun 




requiring no battery 

, "'HE supreme achievement of Magna- 
JL vox engineers represented in a Re- 
producer of truly exquisite tone quality. 

The superb tone quality of M4 results 
from the perfection of the Magnavox 
semi-dynamic operating principle incor- 
porating; first, a new magnetically balanced arm- 
ature; second, an improved type of diaphragm 
supported by hollow rubber gaskets; and third, 
an extremely high resistance winding which 
makes M4 unusually sensitive. 




M4 and other dfttagnavox Radio 
Products can be had of good dealers everywhere 

THE MAGNAVOX CO., OAKLAND, CALIF. 

New York Office: 350 West 31st Street 
Canadian Distributors: Perkins Electric Limited,Tronto, Montreal, Winnipeg 

MAGNAVOX. 

A *M.*Dhe Reproducer Supreme 



Beautifully finished 
in dark enamel with 
gold high lighting. 

Equipped with flex- 
ible cord and West- 
on plug ready to 
connect as simply as 
a head set. 



Tested and approved by RADIO BROADCAST 



174 



Radio Broadcast 



four hours because nothing will tune-out WDAF's har- 
monics while they have their alleged frolic, it can be ex- 
pected that he will be in a different position to most other 
amateurs, so his feeling should not be taken as a general 
one. 

It has often been remarked that the enforced quiet hours 
have reduced interference from amateur stations. This is 
a point which I should like to hear more correctly stated. 
It is true that when this regulation was made, some owners 
of single circuit receivers got less interference, but the 
general interference was not altered at all. Too many 
amateurs are going around confessing that their sets create 
interference, whereas, quite probably they do not. The 
spark is the only type of transmitter which I know does 
create interference serious enough to be noticed. I think 
that even an IC\V set is harmless. 

\Vhile in New York last year, I was listening to 2RK on a 
single-circuit receiver, at a point about a mile distant from 
him, and I found the tuning quite sharp. From experi- 
ments which 1 have made from time to time in the last 
five years, I am inclined to believe that if interference is 
encountered from a CW station, the fault is with the 
receiver. One should never lose sight of this point. As 
a matter of fact, the improvement in design of receiving 
sets is so rapid that I think the present compulsory silent 
period will be lifted in a year or so. 

H. S. GOWAN, 

Kitchener, Ont. 




NOT ALL "APPLAUSE" 

Goes to broadcasters. This card, done in 
full colors, hove in the office not long ago 

"To Begin Wiih, Radio Saved My Life." 

Editcr, RADIO BROADCAST, 
Doubleday, Page & Co., 
Garden City, L. I. 
DEAR SIR: 

You asked some time ago for letters telling "What Radio 
Has Done for Me." Well, to begin with, radio saved my 
life. This I did not fully realize until after my doctors had 
explained it all to me, but now I know it to be true. 

Some two years ago, I found I had serious lung trouble. 
I tried to fight it "standing up" for a while, but soon my 
doctors sent me to Asheville, N. C., where I remained in a 
sanatorium and made no progress. Considering myself a 
gone goose, and preferring to die among my own family 
rather than passing out at Asheville, I came home, down 
and out. I practically gave up, and lost all interest in 
everything. The combined pleadings of my family and 
doctors to buck up, did not make any impression on me 
whatever. 

One day a strange chap came into my bedroom and 
began to fool around with some wires and a box on a small 
table near me. He did not have tnuch to say, and I was 



in such a state that I thought he had something to do with 
my funeral. I rather thought that this stranger's presence 
was only another indication of the complete care my family 
was taking of me and that this was the real beginning of the 
end. 

Then the chap said: "Say old man, try these on your 
head and see if they fit." I wondered whether people were 
now having their heads measured for burial. Anyhow he 
placed the contrivance over my head, and 1 don't think 1 
have been before or since so near heaven as I was then. 
I heard a voice and music and actually believed I was leav- 
ing this earth. 

Making a long story short, I became as interested as a 
six-year-old. The set was installed on Friday and on 
Monday, my doctors said to me, " You have made as much 
improvement in the last three days as we could have ex- 
pected in a month. From then on, I lived in bed with the 
phones on. But I did not stay there very long. . . . 

Not long ago I was out riding with my doctor, who 
remarked to me that I owed my complete recovery not to 
his good work especially, but to the beneficial effect of the 
radio set at the psychological time. 

T. B. S., 

Atlanta, Ga. 

A British Amateur Reports 

Editor, RADIO BROADCAST, 
Doubleday, Page & Co., 

Garden City, L. I. 
DE.VR SIR: 

If you have space for the following, I would like to report 
reception of the following American radio amateurs. I 
used two valve, detector and one low-frequency valve. 
If any of them are interested and can verify same, I would 
be glad of a card. 

Received on 25 November, 1923, about 10:30 p. M. 
E. S. T. 2CXL, 8MZ, 8TR, 8UF, SAGO, 8CPD, 8CPO, 
8XAW, gCR, gAM K, 2EL (working 5HL) 8AMM (work- 



Received 10 February, 1924, about 8 P. M. E. S. T. 
lALJ, lAOL, lAPY, 2OMF, sAIR, gZL, 2CEI (working 
5 AIC), 8COI . 

These dates and times are calculated in Eastern Standard 
throughout. 

Yours truly, 

A. C. SIMONO, 

Wellington Road, 
Mablethorpe, Lincolnshire, 

England. 

"Joy Unconfined" about the Roberts Set. 

Editor, RADIO BROADCAST, 
Doubleday, Page & Co., 
Garden City, L. I. 
DEAR SIR: 

The sole fault I have to find with your famous one-tube 
knock-out reflex receiver is that users frequently run into 
a faulty fixed or variable crystal and as a result grow 
dissatisfied. 

This is borne out by my own experience, for I have had 
wonderful results, when the crystal "was feeling well" on 
three different occasions with all conditions other than the 
crystal the same. So far J have tried several crystals. 
With one semi-fixed crystal I seemed to get the most 
satisfactory results when that was adjusted right and 
fastened, I could get three to four houis of perfect re- 
ception. Then I had all Chicago stations, Detroit, Spring- 
field (Mass), Philadelphia, Fort Worth, Dallas, North- 
field, Atlanta, and once, Oakland, Cal., but apparently 
after that favored spot lost its sensitivity, the set would 



RADIO BROADCAST ADVERTISER 





Send for 32-pape 
illustrated hook giving 
latest authentic in- 
structions on drilling, 
wiring, assemhlingand 
tuning 6 and 8 tube 
Ultradyne receivers. 

50 Cents 

Edited by: 



* , e /yjproveo ir 

SUPER-HETERODYNE 



The Ultradyne employs the "Modulation Sys- 
tem," a basic development by R. E. Lacault, 
A. M. I. R. E., radio engineer of this company, 
and formerly Radio Research Engineer with the 
French Signal Corps Research Laboratories. 

The "Modulation System" places the Ultradyne 
years ahead of all present methods of radio re- 
ception. This new principle increases the sensi- 
tiveness over that of any known receiver. Weak- 
est signals are made to operate the loud speaker. 

Results secured by Ultradyne owners are amaz- 
ing and exceed even those obtained with any 
other receiver under the same conditions. For 
range, signal audibility and faithful performance, 
the Ultradyne commands your first consideration. 

Write for descriptive Circular 

PHENIX RADIO CORP. 

5-7 Deekman St New York 




ULTRAFORMERS 
Types "A" and "5" 

New improved long 
wave radio frequency 
transformers. Type 
"B" may be success- 
fully employed in any 
circuit where long 
wave radio frequency 
transformers are es- 
sential. 

$5.00 

Designed by: 



Tested and approved by RADIO BROADCAST 



176 



Radio Broadcast 



The Torrington Radio Club 

TORR1NGTON, CONN. 

Radio Broadcasting Station 

I wish to acknowledge reception of your 

by on 

at 

Remarks : . 



_M.. E. S. T 



Receiver used 



PRINTED THANKS FROM THE RADIO CLUB 

Members of the Torrington, Conn., Radio 
Club send these cards out to broadcasters 



get only local stations. These locals would come in better 
with the detector contact off. 

Regarding the Roberts knock-out two-tube set, I must 
say I have had excellent success with it. The hardest 
stunt I have asked of it yet was to bring in Louisville on 
400 meters through WJAX on 390. It did its best angels 
could do no more. I heard Louisville right through WJAX 
which isn't bad since there is only ten meters difference 
between the two stations, and Louisville has a power of 5 
k.w., 400 miles away, while WJAX has i k.w. and is about 
four miles away from me. 

I did several things which Roberts did not specify. I 
brought the taps on the A coil out to switch points on 
the panel, which helped selectivity and volume and then I 
put the whole coil on a lever, with a control knob on the 
panel so that the coupling with the primary S coil could 
be varied which is an advantage. The T coil is on a lever 
at the end of a horizontal shaft which can be rotated. 
The coupling can be varied in a vertical plane (fanwise) 
which makes for compactness. With this set last night I 
heard (on the loud speaker) WFI, KFKX, WFAA, WGY, 
WHAS, WOR, WCAL, WBZ, WDAP, KDKA, WGN, 
WOC, and WBAP. 

J. E. ROBERTS, 

Cleveland, Ohio 



Radio and Shorthand 

Editor, RADIO BROADCAST, 
Doubleday, Page & Co., 
Garden City, L. I. 
DEAR SIR: 

When I first became a radio fan, I merely listened- 
in as a pastime. Now I have found another use for 
my radio. 

One can usually tune-in some lecture or talk on 
general topics of the day, and I have found that my 



shorthand has been greatly improved since I started 
the practise of spending about a half hour each 
evening, copying down what I hear. 

I used to think that I got enough practise during 
the day doing my regular work, but in taking dic- 
tation, I find usually I am more concerned in getting 
every word than in neatness of the result. And 
when I am copying what I hear over the radio, it does 
not matter if I miss a few words, and I can pay more 
attention to the size and shape of the shorthand 
characters, and so get splendid practise that I cannot 
get during working hours. 

SALMER PETERSON. 

Arlington, S. Dak. 

Not So Fast, Announcers 

Editor, RADIO BROADCAST 
Doubleday, Page & Co., 
Garden City, L. I. 
DEAR SIR: 

The writer, a radio fan, in the name of all the 
radio fans in the Island of Cuba, respectfully ad- 
dresses to you this letter in order through your 
magazine to call the attention of all the broadcasting 
stations in the United States to the fact that it is 
next to impossible to understand the name or initial 
of the transmitting station because the announcers 
in general speak extremely fast and this, added to 
the static, keeps us from knowing who is trans- 
mitting. 

During the past few months, I have been experi- 
menting in order to ascertain the distance I could 
reach with my receiving set and regularly every 
night hear Los Angeles, Fort Worth, Alabama, 
Davenport, Pittsburgh, and others. I received the 
concerts well, but was not able to identify the 
stations until the second or the third number, due 
to the extreme speed of the announcers when giving 
the initials. 

Undoubtedly you are aware that there are in the 
neighborhood of 25,000 radio amateurs in Cuba and 
they are very much interested in hearing the States. 

If you will be so kind as to write an article in your 
magazine with regard to the above, I can assure you 
the favor will be appreciated by all the radio fans 
in Cuba. 

Yours very respectfully, 
OSCAR H. STA. CRUZ 
Habana, Cuba. 



SIX MEN IN A DIRIGIBLE 

(BATTLING fog and wind, pushing bravely toward the North Pole. . . How the first 

wireless apparatus ever put aboard an airship dramatically saved six lives. . Told 

by Jack Irwin, the Marconi wireless operator aboard Walter Wellman's dirigible AMERICA 

on its fateful Atlantic voyage in October, 1910. The story will appear in an early number. 



RADIO BROADCAST ADVERTISER 



For the Fullest Measure 




of Undistorted Volume 



To obtain the fullest measure of undis- 
torted volume, your receiver must deliver 
to the diaphragm of your loudspeaker or ear 
phones audio frequencies which will produce 
the maximum volume and purest qualities 
of tone. 

This depends directly upon the efficiency 
of your audio amplifying transformers. 
The GENERAL RADIO CO. type 231 -A is 
distinctly a quality transformer of high 
electrical and mechanical efficiency. 
Features contributing to its superior per- 
formance are: 

Low loss steel used in its core construction 
Layer Winding properly insulated and impregnated 
Air gaps in core to avoid distortion 
Unbreakable feet with convenient mounting holes 
Heavy leads with soldered connections 
High and flat amplification curve 

Which indicates that amplification is nearly uni- 
form throughout its entire audio range, making it 
best for all stages. 

Turns ratio 3.7 to 1 Impedance ratio 10 to 1 

Instructive Folder on "Quality Amplifi- 
cation" sent free on request 





"Products of Proven Merit" 



Type 231-A 

AMPLIFYING TRANSFORMER 

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PRICE $5.00 



Sold by Good Radio Dealers 
EVERYWHERE 



GENERAL RADIO COMPANY 

Manufacturers of 
Radio and_Electrical Laboratory Apparatus 

Massachusetts Ave. and Windsor St. 
CAMBRIDGE MASSACHUSETTS 



GENERAL RADIO Co 



Tested and approved by RADIO BROADCAST 




QUESTIONS AND 

X*3 



In writing to The Grid for constructional data, correspondents are requested to send a 
stamped self-addressed envelope with their letter of inquiry and also to furnish the 
editor with all possible information concerning the use to which the apparatus is to be 
put. This should include, when pertinent, type of tube, wavelength, voltage, current, 
sizes, the experience of the correspondent and a description of available material. This 
will greatly add to the facility with which our advice may be carried out, and to the general 
usefulness of this department. * 



QUERIES ANSWERED 

DESCRIBE THE CONSTRUCTION OF A LOOP FOR THE SUPER-HETERODYNE A. S., Farmington, Me. 

WHAT ARE THE DIMENSIONS, NUMBER OF TURNS, ETC. OF THE OSCILLATOR-COUPLER 

FOR THE HAYNES SUPER-HETERODYNE A. C. S., Hazen, Ark. 

How CAN I DECREASE THE RADIATION OF MY SINGLE CIRCUIT "BLOOPER?" . . 0. M. W., Key West, Fla. 
WHAT is THE PURPOSE OF THE GRID LEAK AND CONDENSER? WHAT* is ITS ACTION IN 

A RECEIVER J.C.B., Brooklyn, N. Y. 

Is A TUNED RADIO-FREQUENCY AMPLIFIER MORE TO BE DESIRED THAN THE UNTUNED 

TRANSFORMER-COUPLED TYPE? G.E.C., Seattle, Wash. 

How CAN I ELIMINATE INTERFERENCE FROM LOCAL HIGH-POWERED BROADCASTING STATIONS W. J. S., Chicago, 111. 

WHAT KIND OF A RECEIVER SHALL 1 BUY? WOULD YOU ADVISE TRYING TO BUILD MY OWN? A. D. C., Philadelphia, Pa. 



THE most desirable size of loop for broadcast re- 
ception is a compromise between the more efficient 
larger sizes and the convenience and mobility of a 
small frame. We recommend a square loop, three feet on 
a side, the various dimensions of which are indicated on the 
working drawing of Fig. 2. 

The loop is of the solenoid type, i.e., wound in "box" 
form rather than as a spiral. There are nine turns of wire, 
separated one-half inch, wound in grooves, sawed in the 
end pieces. Any convenient wire may be used. Green 
double silk covered, No. 18 is perhaps the most easily 
manipulated, and when wound on a stained frame, the 
finished loop presents a very creditable appearance. 

The frame is constructed of \" by \\" lumber. The 
upright may be drilled at the lower support on which the 
wires are strung to pass the middle wire. The other wires 
of course pass on either side of the upright. The construc- 
tion of the base is clearly shown, the holes through the top 
and into the bottom being one inch in diameter, and the 
lower eight inches of the upright rounded to fit with 
sufficient looseness to permit turning of the coils. 

Fig. i shows the approximate wavelength range of this 
loop when shunted by the average .0005 mfd. plate con- 
denser. 



This loop is especially adapted for use with the Haynes 
super-heterodyne receiver, and multi-stage radio-frequency 
amplifiers. It may also be used with a proper receiver as 
a direction finder. 



600 
500 
400 
300 
20(7 
100 



20 40 60* 80' 100* iZO" 140 160" 180 
.0005 MFD WITH A COMPARATIVELY STRAIGHT CURVE 

FIG. I 



RADIO BROADCAST ADVERTISER 




Announces a New Audio Frequency Transformer 
and New Variable Condensers 



FADA 

Audio Frequency 
Transformer 

No. 171-A, $6.00 




FADA 

Variable Condensers 

No. 142 (IS 
plates .0003 tnf) 

$3.00 

No. 144 (23 

plates .0005 mf) 

$3.50 



IN KEEPING with its established 
policy of producing only the fin- 
est of radio apparatus, F. A. D. 
Andrea, Inc., announces a new Audio 
Frequency Transformer suitable for 
all circuits, and particularly adapted 
to Neutrodyne receivers. 

A high average amplification over 
all audio frequencies is the out- 
standing accomplishment of this 
new FADA transformer. Encased 
in bakelite with nickeled binding 
posts, it looks twice its worth. Try 
FADA Audio Transformers in your 
receiver and know what uniform 
and distortionless amplification 
really means. 



The name FADA on a condenser 
means just one thing condenser 
satisfaction. The new FADA con- 
denser is made in two capacities 
15-plate, capacity .0003 micro-farads, 
and 23-plate, .0005 micro-farads ; and 
each the exact capacity at which it 
is rated. Radio frequency losses are 
reduced to a minimum by special 
rotor wiping contact brushes. A 
true "low-loss" condenser with an 
efficiency exceeding that of con- 
densers selling at much higher 
prices. 

Dealers are now ready to supply 
FADA transformers and condensers. 



F. A. D. ANDREA, INC., 1581 Jerome Avenue, New York 



Tested and approved by RADIO BROADCAST 



i8o 



Radio Broadcast 




SCREW 

9 'NOTCHES FOB 
LOOP WIRE 



AN OSCILLATOR COUPLER FOR THE HAYNES 
SUPER-HETERODYNE 

DIMENSIONS for a suitable coupler are as follows: 
The stator is of formica or bakelite tubing, 3!" in 
diameter and 2\" long. It has two coils wound on it, 
each of 18 turns of No. 22 D.C.C. wire. The coils are 
separated by a \" space. 

The rotor is of the same material and is 3" in diameter 
and ij" long. One coil of 15 turns of the same wire is 
wound on it. 

Mechanical details of the mounting support and rotor 
shaft have been omitted as these differ in various types of 
standard couplers. The stator coil is set at a 45 angle to 




the base. This reply gives only the dimensions of the coil 
forms and number of turns for each winding. See Fig. 3. 

SINGLE CIRCUITS AND "BLOOPING" 

AN EASY, quick method of changing over your 
single-circuit "blooper" into a double-circuit 
receiver with the chances for radiation materially 
reduced, is shown in Fig. 4. The dotted lines show how 
the circuit looked as a single-circuit radiator. Coils S and 
T are the stator and rotor respectively of a standard 
coupler. Ci is changed from the series antenna connection 
to a shunt connection across the stator which then becomes 
the secondary. The primary consists of about ten turns 
of D.C.C. wire (sizes 24 to 18 will do) wound directly over 
the secondary. This serves as an untuned primary. 

When the wave trap, shown elsewhere in these columns 
is used with this modified circuit, an additional absorption 
circuit is provided which also tends to diminish the radi- 
ation of the type of receiver to a negligible quantity. 




FIG. 3 



FIG. 4 
THE GRID LEAK AND CONDENSER 

THE grid leak and condenser supplies the grid of the 
tube with rapid surges of electron changes. 
The theory of its action is as follows: 
Suppose electrons surge from the tuner windings into one 
side of the grid condenser. The electrons which were on 
the grid side of this condenser will then rush out on to the 
grid of the tube, and cut down the plate current. But this 
will be so quick as to produce no effect in the telephones. 
On the back surge, however, something else will happen. 
The electrons will then rush out of the tuner side of the 
grid condenser to such an extent as to pull some electrons 
away from the grid of the tube, and thereby make it posi- 
tive. This will mean that some of the free electrons in 
the tube will be drawn to the grid of the tube and out on to 
the wire connecting the grid to the condenser. On the 
next return surge of electrons on the tuner side of the 
condenser from the tuner, these extra electrons which 
came from the tube are no longer free, but are trapped 
between the condenser and the grid of the tube. They 
cannot get out of the grid back into the vacuum of the 
tube because the grid is not heated as the filament is. The 
result is that the grid is more negative than it was before 
because of the excess of the electrons it now has. The 
plate current in the tube will therefore go to a lower value 
than it did before. This trapping of electrons will continue 
on each positive swing of the grid so that the grid will soon 
reach an average negative value below where it started, by 



RADIO BROADCAST ADVERTISER 



hours spent to solder 
connections carefully 

. . , wires shortened 
, . circuits altered . . 






Eliminate short circuits with 
MAR-CO SHUR-GRIP jacks- . 
Formica insulation, sterling 
silver contacts, hooked termi- 
nals for quick, leak'proof con- 
nections 60 cents to $1.00 
and well worth it. 



WHAT a tiny fraction of broad' 
casted energy actually gets to your 
set ! How vital it is to prevent a particle 
of that energy from leaking away ! 

Yet in the most carefully constructed set, 
there are scores of places where stations you 
particularly want can literally leak away ! 

For every small part must convey current 
before energy gets to your phones or 
speaker. It's mighty important to you to 
know that every one of them is doing its 
full duty to prevent energy leaks. 

MAR'CO small parts are made with 
precision, by the makers of scientific in- 
struments designed to stop leaks and 
conserve precious energy ! 

The compactness, the sure contacts 
hundreds of thousands have found in 
MAR'CO instruments, would be worth 
high prices. Actually, they save you money 
when you buy . . just as they save stations 
that might otherwise leak away when 
you use them ! 




The compact, leak-proof con' 
struction, and the amazingly' 
smooth, easy operation, of 
MAR'CO neutralizing con 
densers works wonders in 
R.F. circuits. Perfect neutraliz' 
ing of tube capacity for $1.25. 




NEUTRALIZING CONDENSERS 



Tested and approved by RADIO BROADCAST 



1 82 



Radio Broadcast 



itTUINS'MDCC 




FIG. 



The four binding posts allow use of this circuit in various 

ways. For general use, post i goes to the antenna, and 

post 2 to the antenna post on the receiver 

the number of electrons which are trapped. This means 
that the average plate current will be correspondingly de- 
creased, the telephones will be affected by this decrease in 
plate current. It is therefore necessary to bring the grid 
back to its original condition if the oscillations in the 
antenna have stopped. 

The grid leak which is shunted across the grid con- 
denser permits the trapped electrons to "leak" out into 
the set. For further details see the interesting and helpful 
book, The Radio Pathfinder, by R. H. Ranger. 

TUNED R. F. AMPLIFIERS VERSUS UNTUNED R. F. 
AMPLIFIERS 

THERE is something to be said in favor of both of the 
methods of radio frequency amplification mentioned. 
The transformer system needs no adjusting, per 
stage. Excepting for the ordinary tuning of the input 
coupler controlling the received wave, there is no further 
adjustment of the tuner. 

In the tuned R. F. amplifier each stage must be tuned 
separately to resonance with the incoming wave. This 
operation is complicated and not always easy. But, when 
each stage has been properly adjusted, the reception is 
exceptionally good. One drawback of a set having tuned 
radio-frequency amplification is that the self-oscillations 
of the tubes make it a difficult set to control. This has 
been partly overcome by incorporating in the set, neutral- 
izing capacities, resulting in a circuit similar to the standard 
neutrodyne set. The disadvantage in using untuned trans- 
formers is that they will not work with the same efficiency 
on all wavelengths. The wavelength at which best re- 
sults are obtained is called the "peak." 

INTERFERENCE AND THE WAVE-TRAP 

IN A recent article by Mr. A. J. Haynes (November, 
1923) this question of e iminating local interference 
was answered in detail. However, Fig. 5 shows the 
circuit diagram for a wave trap which will accomplish this 
elimination. 



The inside winding is a coil consisting of 45 turns of No. 
24 D.C.C. wire wound on a 35" diameter tube, 2" long. 
The outside coil is wound directly over the first coil, being 
separated by a piece of linen or cambric cloth. It consists 
of 10 turns of No. 24 D.C.C. wire. Figs. 5 and 6 show 
the circuit, and method of coupling to a receiver. 

CHOOSING A RECEIVER 

THERE are several limitations that must be taken 
into consideration when choosing a receiver. Those 
of first importance are: amount to be spent; location, 
i.e., use of loop or outdoor aerial; purpose of its use, i.e., 
general broadcast reception for entertainment or experi- 
mentation. 

A one-tube reflex set is comparatively cheap, efficient in 
operation, and has the advantage of working a loud speaker 
for local reception. 

A three- tube reflex will permit the reception of distant 
stations on a loud speaker, is selective in tuning and is 
generally conceded to be a standard type of home receiver. 
A three-tube regenerative set is also excellent although the 
novice experiences some difficulty at first in effectively 
operating it. 

A five-tube neutrodyne is an exceptional distance- 
getter, but on account of the multiplicity of controls is 
rather unwieldy to handle for one who knows nothing at 
all about radio. 

The super-heterodyne is the "high-powered" par excel- 
lence receiver of radio. Simple in operation and effective 
for long distance reception, this set can surely be called 
the highest type of radio receiver yet developed. Most 
super-heterodynes are designed for loop reception. 

The sets described will fit all sizes of pocketbooks and all 
have been described in past issues of RADIO BROADCAST. 

There is an advantage to building your own since the 
experience gained enables one to understand the workings 
of the set. If one is especially handy with tools, the build- 
ing of a set is heartily recommended. 

In the May issue of the Grid a list of receivers that do 
not radiate, was given. We advise prospective purchasers 
of radio receivers to consult this list. 



VARIABLE CONDENSER 



ANTENNA 




INSIDE WINDING 



FIG. 6 



~LJOW to build a broadcasting station using two five-watt tubes, is the subject of an unusually 
complete how-to-make-it article wbicb will appear in this magazine for July. It is written by 
Ashley C. Dixon of Stevensville , Montana, owner of station KFJR and author of 'What Radio 
Means at a Rocky Mountain Ranch" in RADIO BROADCAST for January. 



RADIO BROADCAST ADVERTISER 




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New Equipment 




SICKLES DIAMOND WEAVE COIL 

A coil of substantial construction which 
largely eliminates bulky insulating ma- 
terials. It is readily mounted and does 
not require a great amount of space. The 
distributed capacity is material reduced 
and at final analysis it is quite efficient 
electrically. These inductances have been 
made to supply the demand for the coils 
Ti and Ta in the RADIO BROADCAST 
Knock-out sets. Made by the F. W. 
Sickles Company, Springfield, Mass. 



HAMMARLUND MODEL 
"B" CONDENSER 

A well built piece of ap- 
paratus which reduces elec- 
trical losses to a minimum. 
The plates of hard brass are 
pressed into slotted brass 
posts and soldered, thus 
eliminating the possibility 
of material dielectric losses. 
Body capacity effect is pre- 
vented by grounding the 
aluminum end plates mak- 
ing it unnecessary to use shielding. The vernier control 
used makes extremely fine tuning possible as well as 
accurate logging. Made by Hammarlund Mfg. Co., Inc., 
144-146 West i8th St., New York City 





99999 



COMO TRANSFORMERS 
A sturdy pair of push-pull transformers, 
one input and one output. Using these, 
the radio fan can build a very satisfactory 
push-pull amplifier. Made by The Como 
Apparatus Company, 446 Tremont St., 
Boston, Mass. Price $12.50 per pair 



ACCURATUNE MICROMETER 

DIAL 

This is a control which not only adds 
to the appearance of your set but 
also makes for fine tuning. The 
micrometer adjustment is very effec- 
tive on the most critical receivers. 
Made by The Mydar Radio Com- 
pany, Newark, N. J. Price $3.50 





GNOME BRAND RADIO TOOL KIT NO. I 

A kit which is worthy the attention of radio fans 
generally. It contains all the tools which would 
ordinarily be needed by the home builder of receiv- 
ing sets and the quality is first class. Hammacher, 
Schlemmer&Co., Inc., New York City. Price $20.00 



MOUNT 
CONDENSER 
HERE 




ELECTRAD VARIOHM 
A variable resistance rated by the 
manufacturers between five thou- 
sand and one hundred thousand 
ohms. Designed for panel mounting 
with adjusting knob. It may be 
used as the coupling resistance in 
resistance-coupled amplifiers. Made 
by The Electrad Corporation, New 
York City 




Licensed under Armstrong U. S. Patent No. 



MacMillan Listens to Honolulu 

and New Zealand "Tunes In" California 




From a little ice-bound 
schooner eleven degrees 
from the North Pole comes 
this message: 

"Am very thankful that 
Arctic Exploring Ship Bow- 
doin is equipped with com- 
plete Zenith radio apparatus. 
Here at top of world, in dark- 
ness of great Arctic night, we 
have already listened to sta- 
tions practically all over the 
United States, from Europe, 
and even from far away 
Honolulu. Zenith has united 
the ends of the earth. MacMillan." 

Again, from far-off New Zealand comes a report 
of radio reception even more startling: 

"It may interest you to know that the writer last 
evening landed KGO, Oakland, California, between 
6 :45 and 7 :30 P.M. Heard his call four or five times 
distinctly, and jazz music. As San Francisco is 6,300 
miles from New Plymouth, and only one tube was 
used, we think this is a very fair performance." 

(signed) H. Charles Collier. 

The sets used by Captain MacMillan and Mr 
Collier are earlier models since improved by the 
addition of a third stage of audio frequency. These 
new models represent an achievement not dupli- 
cated in any other set on the market. Write to-day 
for full particulars and name of nearest dealer. 

Zenith Radio Corporation 

McCORMICK BUILDING, CHICAGO. ILLINOIS 



using 



Long-Distance Radio 



The new Zenith 
3R -Long-Dis- 
tance" Receiver-Amplifier com- 
bines a specially designed dis- 
tortionless three-stage amplifier 
with the new and different Zenith 
three-circuit regenerative tuner. 
Fine vernier adjustments- in 
connection wHhthe unique 
zenith aperiodic or non-resonant 
"selector" primary circuit make 
possible extreme selectivity. 

2,000 to 3,000 Miles With 
Any Loud-Speaker 

With the new Zenith 3R satisfac- 
tory reception over distances of 
2,000 to 3,000 miles, and over, is 
often accomplished in full vol- 
ume, using any ordinary loud-speaker. The Model 3R is 
compact, graceful in line, and built in a highly <*-| f-(\ 
finished mahogany cabinet - =vpi.U\/ 

Tl/tnftal A I? The new Zenith 4R " Long-Distance " Re- 
lvM.Ofld tl\ ceiver- Amplifier comprises a complete 
three-circuit regenerative receiver of the feed-back type. 
It employs the new Zenith regenerative circuit in combination 
with an audion detector and three-stage audio-frequency 
amplifier, all in one cabinet. 

The Zenith 4R may be connected directly to any loud- 
speaker without the use of other amplification for full phono- 
graph volume, and reception may be satisfactorily dj Q tf 
accomplished over distances of more than 2,000 miles vj> O J 



r 



ZENITH RADIO CORPORATION, 

Dept. 1-G 328 South Michigan Avenue, Chicago, 111. 

Gentlemen: 
Please send me illustrated literature on Zenith Radio. 



Name. . . 
Address . 



Tested and approved by RADIO BROADCAST 



New Equipment Continued 




RADIO TUBE CONTROL 
UNIT 

A compact device combin- 
ing rheostat, vernier and 
potentiometer mounted as 
one unit, with two knob 
control. It is made of 
moulded bakelite. One 
knob controls the rheostat 
and the vernier, the other 
knob controls the poten- 
tiometer lever. Made by 
Herbert H. Frost, Inc., 
Chicago, Illinois. Price 
fi-75 




PONS RADIO 
AND BAT- 
TERY CLIP 

An inexpensive 
clip with a 
spring in the 
center and jaws 
on either end 
which makes 
this device val- 
uable wherever 
there are radio 
sundries. The clip may join two batteries, or place tele- 
phone leads in series among other uses. Made by Eugene 
Pons, 838 Lincoln Ave., Schenectady, N. Y. 




A SUPER-HETERODYNE 

The photo shows what has been done with parts manu- 
factured by the Radio Receptor Company, New York City 



Supplemental List of Broadcasting Stations in the United States 

LICENSED FROM MARCH 21 TO APRIL 18 INCLUSIVE 

LEXERS LOCATION 

KFFP Moberly, Mo 

KFPH Salt Lake City, Utah 

KFPL Dublin, Texas 

KFPM Greenville, Texas 

KFPN Jefferson City, Mo 

KFPP Olympia, Washington 

KFPQ Denison, Texas 

KFPR Los Angeles, Calif . 

KFPS Casper, Wyoming 

KFPV San Francisco, Calif 

KFPW Carterville, Mo 

WABB Harrisburg, Pa 

WCBO Memphis, Tenn 

WCBQ Nashville, Tenn 

WQBR Providence, R. F 

WCBT Worcester, Mass 

WCBU Arnold, Pa 

WCBV Tullahoma, Tenn 

WDBF Youngstown, Ohio 

WEAR Baltimore, Md 

WHO Des Moines, Iowa 

WIAY Washington, D. C 

WLS Chicago, 111 




TOTALS 

Number of U. S. broadcasting stations 598 

Number of Canadian broadcasting stations 44 

Number of Cuban broadcasting stations 34 



HADIO BROADCAST ADVERTISER 



Atlas 



TRADE MARK 



LOUD SPEAKER 

The Musician of the Air" 




TRADE MARK 



Complete $25 




Atlas Unit with 
phonograph coupling $13.50 



Presidential Conventions! 

The Republican Convention, 
Cleveland, June 10. 

The Democratic Convention, 
New York, June 24. 

A Message to 

the Public! 

THE very next best thing to being actu- 
ally present at these two events, of 
national and international importance, is 
to hear their ATLAS RE-PRODUCTION. 
Bring these momentous proceedings and 
orations right into your home in all their 
original naturalness for the entertainment 
and instruction of your family and friends. 
Get all of these speeches, every word clearly 
inflected, in the full, undistorted tones of the 
speaker. Just as realistic as though you 
were actually there. Buy your ATLAS 
NOW! 

Booklet "A " upon request 



Multiple Electric Products Co.Inc. 

Makers of Mono TIME- LAG FUSES Multiple 

2 ORANGE ST. NEWARK, N. J. 

District Offices in 

Boston, Mass. Philadelphia, Pa. Baltimore, Md. Pittsburgh, Pa. Detroit, Mich. 
Chicago, 111. St. Louis, Mo. Denver, Colo. San Francisco, Cal. 

Sole Canadian Distributors: 
Marconi Wireless Telegraph Co. of Canada Ltd., Montreal, Canada. 



Tested and approved by RADIO BROADCAST 




Our Authors 



THE artist who is responsible for our 
cover this month is Remington Schuy- 
ler. In Wyoming, he is known to the 
Indians as Ta-tan-ka-luta, which, being 
translated means Red Buffalo. Mr. Schuy- 
ler is regarded as a highly authoritative 
painter of Indians, even by the Indians 
themselves. At his home in New Rochelle, 
N. Y., Mr. Schuyler has done much for the 
Boy Scouts, who, naturally enough, are not 
unenthusiastic about close associations with 
a real Westerner. 

JULIAN KAY is a radio man who was 
toying with spark coils and unwilling 
crystal detectors back in the days when an 
antenna atop a house was a matter for un- 
comfortable neighborly astonishment and 
disapproving shaking of heads. He and the 
editor were discussing the present Greek 
confusion of radio names one day, where- 
upon Mr. Kay waxed so enthusiastic that 
his present excellent article is the result. 
There are several others to follow. 

ZEH BOUCK is a busy contributor to 
our magazine. Of late, he has associated 
himself with the William P. Mullaly Com- 
pany, advertising agents, and has organized 
a radio department for them. When we 
talked with him recently, he was momen- 
tarily three centuries away from radio, deep 
in the absorbing 
pages of Burton's 
Anatomy of Melan- 
choly. 




W! 



CARL DREHER 



r ITH design- 
ing malice, 
we think, Carl 
Dreher took this 
snapshot himself 
atop ^Eolian Hall, 
which houses the 
apparatus of WJZ 
and WJY, with the 
purpose of showing 
that he is quite 
above radio, but we know better, though 
he writes: "In my spare time I am a prac- 
titioner of the art of writing fiction. En- 
gineers all say I am a good writer, and 
writers praise me as an engineer. As a 
result of this striking unanimity of opinion, 
I don't know what the devil I am." Mr. 
Dreher does not always put himself on a 
pedestal. 



THERE are few men who have been ra- 
dio operators who have had a jollier 
time at it than George F. Worts whose thrill- 
ing, straightforward tale of one eventful 
night on the miscalled Pacific appears in this 
number. Mr. Worts has been in most of 
the ports on both sides of the Pacific in most 
of the many types of ships one finds there. 
Now he is living in the center of that inter- 
esting colony of artists and writers at 
W T estport, Connecticut, where he writes the 
magazine stories which many of us enjoy. 

HF. MULLETT 
is on the staff 
of the Edmonton Jour- 
nal and confides that 
he is English by birth, 
but really can't help 
that. "I came to 
Canada on the night 
boat twelve years 
ago," he writes, " suc- 
cessfully evading the 
line-up of creditors at the docks. For five 
years I worked for the Alberta government, 
but reformed and went into journalism." 




H. F. MULLETT 




R 



R. E. SHLUKBIER 



E. SHLUK- 
BIER is a na- 
tive of Michigan 
Saginaw, to be ex- 
act. During the war, 
he went through 
the Harvard Radio 
School, later became 
a* Naval operator 
with the fleet, and 
since his demobiliza- 
tion has been a com- 
mercial operator in 
the merchant ma- 
rine. " A Word from the Enemy" is the re- 
sult of opinions thought out during quiet 
tricks at the key. 

BOWDEN WASHINGTON sends his 
article "How to Build a Teledyne Radio 
Receiver," from Minneapolis where he is 
now located as chief engineer of The Cutting 
& Washington Radio Corporation. In 1916 
he joined with Dr. Fulton Cutting, forming 
the firm with which he is now connected. 
"In 1917," Mr. Washington writes, ;< I 
developed the first new marine transmitter 
since 1907, of which more than $750,000 
worth were made and sold." 



RADIO BROADCAST ADVERTISER 



Watch the radio col- 
urns of your newspaper 
for the big convention 
broadcast schedules. 







Cheer with the Galleries 

When the Delegates March In! 



Radiola Superheterodyne 

It needs NO ANTENNA 
no ground no connections of 
any kind. Has a handle to lift 
it by. Tunes in with just two 
knobs that you turn to marked 
spots on the dials. Tunes out 
powerful near stations to get 
the far ones. A wonderful new 
achievement in the perfection 
of its tone its sensitivity 
and its supreme selectivity! 
Complete with six Radiotrons 
UV-199 and Radiola Loud- 
speaker; everything 
except batteries . . 



External, rotating loop, easily as- 
sembled, larger than self contained 
loop in Radiola Super-Heterodyne, 
for extreme reception range. 

Loop A Q 814 $12.00 



There are many Radiolas at many prices. 

Send for the free booklet that 

describes them all. 



No "influence" needed this year for a gallery seat at 
the big political conventions ! Get it all, with a 
Radiola Super-Heterodyne. 

When the delegates march in their banners stream- 
ing; when the bands play and the galleries cheer 
be there with the "Super-Het." Hear the pros and 
cons as they fight their way to a "platform" for 
you. Hear the speeches for the "favorite sons." 
The sudden stillness when the voice of a great speaker 
rings out. The stamp and whistle and shrill of com- 
petitive cheering. Hear the actual nomination of a 
president. 

It used to be all for the delegates' wives and the 
"big" folks of politics. Now it's for everybody. 
Listen in. Get it all! With the newest Radiola. 

Radio Corporation of America 



RADIO CORPORATION OF AMERICA 

Dept.36 ( Address office nearest youj 
Gentlemen: Please send me your free 
Radio Booklet. 

Name 



| Address 



233 Broadway 
New York 



Sales Offices 

10 So. LaSalle Street 

Chicago, 111. 



433 California Street 
San Francisco, Cal. 



Radiola 



REG. U. S PAT OFF 



Tested and approved by RADIO BROADCAST 




WALTER VAN BRAAM ROBERTS 

One of the most highly regarded of the present radio technicians. He is designer of the Roberts Knock-Out Two-Tube 

set (RADIO BROADCAST for April and May), and author of "A Practical Super-Heterodyne using icjg's" (August, 1923), 

and the technical serial "What Makes the Wheels Go "Round." He is a graduate of Princeton University and is now 

doing research work there at the Palmer Physical Laboratories 



RADIO 
BROADCAST 



Vol. 5, No. 3 




July, 1924 



England's Venture into Broadcasting 

The British Listener-in and Amateur What the " Broadcatcher " Gives and What He 
Receives Nine Hearts That Often Beat as One Problems of Radiation and Other Inter- 
ference The Cost and Quality of British Apparatus Some General Observations 

By WILLIAM H. GARY, Jr. 



LONDON. 

Ov! THE whole, the radio bearings 
are well oiled, here in England. 
This, at least, is the impression 
one is likely to receive after 
talking with B. C. L.'s, ama- 
teurs, radio editors, engineers, and others, 
and after listening, from various points in and 
near London, to the signals that pass in the 
night. And why not? Considering the cau- 
tion with which Great Britain entered the 
broadcasting game her profiting by the ex- 
ample of the "Yanks", her establishment of a 
British Broadcasting Company to control the 
nine stations (only nine, not five hundred and 
seventy-five), and her foresight in technical 
and administrative matters good results are 
naturally to be expected. The advantage of 
having all transmission under a single control 
was brought home to me the first night I 
listened-in. 2LO was on, and it was a few 
minutes before an opera was due to fill the air. 

"You will find on page of your Radio Times 

for January ," came the announcer's voice, 

"a summary of the opera and some comments 
on the music and its composer." This hap- 
pened to be an " S. B. (Simultaneous Broadcast) 
to all stations," so that from Aberdeen to 
Bournemouth, from Cardiff to London, sub- 



scribers to this official weekly of the B.B.C., 
and those who had planked down their tup- 
pence for a copy at a newsstand could post 
themselves on the forthcoming music. 

According to Post Office figures, about 
600,000 broadcast listeners have so far taken 
out licenses. In November alone, between 
40,000 and 50,000 new licenses were issued. 
There undoubtedly exist some low wretches 
who make their own sets and listen-in for 
nothing, leaving the financing of the programs 
to honest folk. But the general opinion seems 
to be that evaders are few, and that the 10 or 15 
shilling charge* (depending upon the kind of 
license wanted) does little to prevent people from 
buying or making receivers. One experimenter 
one, by the way, who had heard America 
during the Transatlantic Broadcasting Tests 
in November thought that people who paid 
out their shillings for a receiving license might 
very likely invest rather heavily in a set or in 
parts, so as to be sure and get their money's 
worth during the twelvemonth. This recalls 
the old absurdity of the Irishman who stuffed 
a five-dollar bill down a crack in a boardwalk, in 
order to make it worth while to rip up the walk 
and recover a nickel that he had lost there. 



^Equivalent to about $2.20 and $3.30. 



IQ2 



Radio Broadcast 



At any rate, in England there is a lively 
interest in broadcasting. Across the street 
from a fifteenth-century church in a quiet little 
village in Hertfordshire (and sandwiched in 
between a shop displaying tripe and flounder 
and one exhibiting Scotch whiskey, brandies, 
etc.), 1 came upon a store devoted exclusively 
to the sale of the latest receiving apparatus. 
In backyards visible from trains passing 




A COMPACT SET 

The cabinet contains everything necessary except a loud- 
speaker The closed cabinet is shown on the next page 

through the outskirts of London, the number 
of antennas is reminiscent of the view from a 
N. Y., N. H. & H. train up beyond i25th 
Street, New York. Or even worse. I counted 
ten parallel antennas in ten adjoining back- 
yards. In town, on every hand there are radio 
stores, and electrical shops selling radio as a 
sideline. Enthusiasts who are not inside 
ardently "talking shop" gaze silently with 
covetous eyes at the window displays as 
we do at home. Magazine stands are full of 
radio periodicals and the periodicals are full of 
both good and not-so-good stuff, with a fairly 
healthy proportion of "ads." 

Some of the non-technical schools are teach- 
ing radio theory and construction to the 
younger boys; notably the London County 
Council Schools. I am told that red-cheeked 
twelve-year-olders are making one shilling do 
the work of two by strategic shopping around 
for grid leaks, coils, and whatnot. 

WHAT THE PROGRAMS ARE LIKE 

THE quality of the B.B.C.'s transmissions 
seems to be excellent. If there is any 
kick coming and of course there is: 600,000 
listeners cannot be expected always to chant 
the same refrain it is due to the fact that some 
thousands of the audience may want jazz while 
other thousands may prefer news or opera. 
And, unlike the listener-in in America, who 
can often choose any one of twenty programs, 
the Englishman must, during the frequent 



periods of "S.B. to all stations," take what's 
offered unless he can tune-in something made 
in France. As a matter of fact, the S.B.'s are 
generally well worth listening to the dance 
orchestra from the Savoy Hotel, for instance. 

One of the most popular programs staged by 
the British Broadcasting Company ismusicfrom 
"The Old Vic," a sort of secondary national 
opera house. It is situated about a mile from 
Marconi House where are the transmitting 
plant and antenna on the south side of the 
Thames. A land line was used at first to 
bridge the gap, but it was both inconvenient 
and noisy. Finally, Captain A. G. D. West, 
Assistant Chief Engineer of the B. B. C., in- 
stalled apparatus in The Old Vic for transmit- 
ting on low power and low wavelength; these 
transmissions were picked up by 2LO and put 
on the air on 365 meters. 

Since the November transatlantic tests, by 
the way, new wavelengths have been assigned 
to most of the original eight* British stations. 
As follows: 



Station 



Location 



Wavelength Wavelength 
During at 

Tests Present 



2LO 


London 


2BD 


Aberdeen 


5 IT 
6BM 


Birmingham 
Bournemouth 


5 \VA 
5SC 
2ZY 


Cardiff 

GlaSgOW 

Manchester 


5 NO 


Newcastle 



363 

495 

423 

385 
353 
4'5 
37^> 

4011 



365 
495 
475 
385 
35 
420 
400 
435 



Here is a complete program from station 
2LO, chosen at random: 

Monday, Jan. 7, 1924 

3.30-4.30. Concert: The Wireless Trio and Frank Foul- 
ton (Bass-Baritone). 
5.00. WOMEN'S HOUR: Ariel's Society Gossip. A 

Newspaper Story from "Whirligigs," by O. Henry. 
5.30. CHILDREN'S STORIES: Songs by Uncle Rex. 

"Jack Hardy," Chap. 16, Part I., by Herbert Strang. 
6.15. Boys' Brigade News. 
6.25-7.00. Interval. 
7.00. TIME SIGNAL AND iST GENERAL NEWS 

BULLETIN. 5. B. to all stations. 

JOHN STRACHEY (the B.B.C. Literary Critic): 

"Weekly Book Talk." S.B. to all stations. 

Talk by the Radio Association. S.B. to all Stations. 

Local News and Weather Forecast. 
7.35 .THE LONDON 8 CONCERT PARTY. 
S.li. to all Stations 

Introducing each other. 

Quartette, "Come to the Fair" (Easthope Martin) . 

COLTON, TARRI, VIRGO, COPELAND 



*To these should be added a ninth station, Sheffield, 
which now not only transmits "S. B.'s" from London, but 
offers programs originating in its own studio. Its wave- 
length at present is 300 meters. It has not yet been 
assigned a call 



England's Venture into Broadcasting 



'93 



Instrumental Trio, "Extase" (Louis Ganne) 
JOAN DUFF, DOROTHY ALWYNNE, WALTER 

NUNN 
Song, Devon Dialect Song 

STANLEY HAYSMAN 
Bag-pipes Song and Story 

TOM COPELAND 
Violin Solo, "Gypsy Airs" (Sarasatc) 

DOROTHY ALWYNNE 

Humorous Trio, "Willie Brewed a Peck o' Malt" (Burns) 

.... VIRGO, HAYSMAN, COPELAND. 

Humorous Imitations on "Coal Black Mammy" 

(Subtle Tarri) .... SUZETTE TARRI 
Song. "On With the Motley" (Leoncavallo) 

WILFRID VIRGO 

'Cello Solo WALTER NUNN 

Anglo-Scottish Interlude TOM COPELAND AND 

SUZETTE TARRI 

Song, "Love's a Merchant" . . . EVA COLTON 
Piano Solo, Waltz Chromatic (Godard) JOAN DUFF 
Final Medley, Old Songs (arr. Su-ette Tarri) THE 8 
9.15 MR. H. GERMAN (President of the National 
Farmers' Union) on "The Farmers' Position To-day." 
S.li. to all Stations. 

9.30. TIME SIGNAL AND 2ND GENERAL NEWS 
BULLETIN. S.B. to all Stations. 
Local News and Weather Forecast. 

9.45. "THE MEISTERSINGERS," Act III. (Wagntr), 
relayed from The Opera House, Covent Garden. S.13. 
to all Stair ons. 
i i.i '). Close down. 

Announcer: R. F. Palmer. 

It is evident that the engineers and execu- 
tives of the B. B. C. are doing their very best, 
and their best is pretty good. One listener 
recently wrote to the editor of the Radio Times. 

DEAR SIR: 

Will you please have one rotten program at least 
once a week, so that 1 may have an opportunity of 
having a night out occasionally without regrets? 
Yours faithfully, 
J. F., London, W. 

The Wireless, Review, a weekly, commenting 
on a discussion that had been stirred up in one 
of the daily papers on the subject of the pro- 
grams, says, "It was- noted that most of the 
contributors to the discussion were in favor of 
programs being at least as serious as at present. 
There were some who wanted all jazz, but they 
were comparatively few. . . . It is grati- 
fying to know that as far as the correspondence 
went, it was a distinct endorsement of the 
present policy of the B. B. C." 

ADVERTISING NOT ALLOWED ALOUD 

A 5 WITH our stations in America, it is all 
well enough to broadcast " Yes, We Have 
No Bananas," but not to add that so-and-so's 
store, at such-and-such an address, expects a 
consignment of the yellow fruit next week and 
will sell it at so-much a bunch. In fact, an 



attempt is made to drown all direct advertising 
before its eyes are open. Manuscripts are 
always censored before they are allowed to be 
read into immortality. I am told that when 
a talk on modern novels, for instance, is given, 
the publisher's name is not mentioned; and 
that when phonograph records are used (as in 
tests or for certain children's programs), the 
name of the piece is given, but not the make 
of the record. 

English people seem inclined to think that 
direct advertising by radio in America is more 
flagrant than is really the case. Some of them 
have also the impression that the air with us 
resembles a delirious person's dream about 
bee-hives. I have assured them that only on 
exceptionally clear evenings and on exceptional 
receivers do all 575 of our stations bombard 
that receiver at one time. 

TROUBLE FROM RECEIVERS THAT RADIATE 

THE situation regarding interference from 
oscillation is a peculiar one in Great 
Britain. When the British Broadcasting Com- 
pany first started in, under the supervision of 
the Post Office, there was considerable fear 
that tube sets would cause trouble. Officials 
thought of the storm of whistles and squeaks in 
America, and turned up their mental coat- 
collars. Accordingly, the Post Office then 
undertook to test all sets which were to bear 
the official stamp of the B. B. C., to make sure 




A POPULAR RECEIVER 

With the British listener-in. He is just as 
avid as his American cousin, reports Mr. Gary 



that they would not radiate sufficiently to 
cause interference; and it was made illegal to 
sell for broadcast reception any complete set 
not bearing the official stamp. Later on, how- 
ever, many people who had little technical 
knowledge wanted to build their own apparatus. 
A special license was provided, allowing them 
to do so, and knowledge of the proper operation 
of receivers was spread as widely as possible. 



194 



Radio Broadcast 



But one good squeak deserved another, so it 
seemed, and recently there has been a marked 
increase in the amount of interference from 
bloopers. B. B. C. officials were and still 
are alarmed ; listeners-in were likewise person- 
ally affected. The blame was placed principally 
upon those holding Experimental Licenses and 
those holding the more recently established 
Constructor's Licenses. But the Post Office 
no longer tests receivers for oscillation, but 
only for wavelength range. Mr. Hugh S. 
Pocock, Editor of the Wireless World, says in 
a recent number of his magazine: 

Exactly what circumstances have brought about 
such a complete reversion of policy on the part of the 
Post Office is difficult to follow. Probably it is out 
of consideration for the manufacturers who were 
naturally very seriously handicapped in the design of 
receivers when they had to make them pass the test 
of non-radiation. In fact, it is exceedingly difficult 
to design a truly efficient receiver which will pass 
such a test. 

Is it surprising that interference from oscillation 
should be so much on the increase, remembering that 
these sets go usually to complete novices who hold 
broadcasting licenses? If it has been found that 
official broadcast receivers cannot be satisfactorily 
designed for non-radiation, then surely publicity 
should be given to the fact, in order that those using 
them shall be aware of the interference they may 
cause and learn how to operate their sets in order to 
avoid interference. 

The law is laid down for holders of the 
Experimenter's License in these words: 

"The apparatus shall not be used in such a 
manner as to cause interference with the 
working of other stations. In particular, re- 
action (regeneration) must not be used to such 
an extent as to energize any neighboring aerial." 

Thus the man who "lives like a star and 
dwells apart" may obtain the advantages 
which a regenerative receiver will give, yet 
without disturbing any one; but the town- 
dweller must "watch his step" (or as many 
"steps" as he is using). 

The fact is, the single-circuit regenerative 
hook-up, not unknown on the west side of the 
Atlantic, is extensively used on this Island, 
although vocal and printed expression regard- 
ing it parallels what we have become used to at 
home. To avoid interference from oscillation, 
various other circuits have been brought 
forward. Reflex sets have been much in 
vogue, and neutrodyne receivers are beginning 
to find considerable favor in the eyes of many 



enthusiasts. Super-heterodynes have been 
used by advanced amateurs for some time, but 
not generally; they are expensive, and, for the 
reception of any British broadcasting, un- 
necessary. 

Interference from other sources does not 
seem to be particularly serious. Set-owners 
who live along the coast have occasion to think 
horrid things of the naval and commercial 
stations now and then; and sometimes ama- 
teurs invade forbidden wavelengths. The 
latter, working on 440 meters (the length allow- 
able for C. W. and telephony only) have been 
requested to "pipe down" during what are 
known as the Main Broadcasting Hours 5 
to 1 1 P. M. daily and at certain other hours on 
Sundays. 

LICENSES AND WHAT THEY INVOLVE 

AT PRESENT there are three classes of 
receiving licenses. The Broadcast Li- 
cense, which costs 10 shillings a year, allows the 
holder to listen-in to whatever he may be able 
to hear. He agrees that his "receiving set, 
and any valve, amplifier, head-telephone, or 
loud speaker used therewith, will bear the 
official trade-mark of the British Broadcasting 
Company." 

The holder of a Constructor's License pays 
15 shillings a year, and certifies as follows: 
" My receiving set will be made or put together 
by myself; and in its construction 1 will not 
knowingly use parts manufactured elsewhere 
than in Great Britain or Northern Ireland." 

The third class is known as the Experi- 
menter's License. It costs 10 shillings a year 
and permits the holder to use any kind of 
apparatus in his set, but "Applicants must 
satisfy the Postmaster General that they have 
in view some object of scientific value or 
general public utility and that they are compe- 
tent to carry out experiments in wireless 
reception." On the application blank appears 
also this: 

Strikeout (A) or (B): 

(A) I declare that the proposed installation will 
not be used for the reception of broadcast programs 
except for experimental purposes. 

(B) I desire also to use the proposed installation 
for the reception of broadcast programs for the pur- 
pose of entertainment and I agree on that account 
to pay a license fee of 155. (instead of IDS.) per 
annum. 

The holder of the first two classes of license 



England's Venture into Broadcasting 



'95 



needs only to fill out a blank at his local Post 
Office, and pay over the stipulated ten or 
fifteen bob. The would-be experimenter, how- 
ever, "shall produce evidence of British 
nationality and two written references as to 
character. A certificate of birth should be 
furnished if possible; but this will not be in- 
sisted on if the referees testify of their own 
knowledge that the applicant is of British 
nationality." His license is obtained through 
the General Post Office in London. 

The regulations governing the British ama- 
teur transmitting license may be interesting to 
American "hams." The requirements regard- 
ing evidence of British nationality, references 
as to character, and birth certificate are the 
same as for the Experimenter's License just 
mentioned. Among other things, applicants 
must also "satisfy the Postmaster General that 
they have in view some definite object of 
scientific value or general public utility. If 
scientific research is intended, they should be 
certified as competent investigators by a 
Government Department or some recognized 
scientific body." By examination or otherwise 
the applicant must satisfy the Postmaster 
General that he has attained: 

(a) A sufficient knowledge of the adjustment and 
operation of the apparatus which he wishes to work. 

(b) An operating speed of at least 12 words 
(Morse)* a minute, sending and receiving. This 
qualification is necessary even when wireless tele- 
phony only is used, in order that the person in charge 
of the station may be in a position to act upon 
instructions in the Morse code issued by Government 
and commercial sta- 
tions. 

A fee of 55. will 
be charged for the 
examination referred 
to above, when neces- 
sary. 

The person in 
charge of a sending 
station must also 
make himself ac- 
quainted with the 
regulations of the In- 
ternational Conven- 
tion in so far as they 



relate to the prevention of interference and impose 
certain duties on all wireless operators. 

Also: 

"For each station authorized to use power up 
to 10 watts, the charges, which will cover the use of 
receiving as well as sending apparatus will comprise 
an initial licensing fee of los. plus an annual fee of 
i, payable in advance. . . . Higher fees will 
be charged for more powerful stations. 

Thecombined height and length of theantenna 
must not exceed 100 feet. For spark, I. C. W., 
C. W., and telephony, the wavelength band 
from 150-200 meters is reserved for the British 
amateur. He may operate within this range 
during broadcasting hours (although not on the 
44O-meter wave, as mentioned above). In any 
case, the amateur may not transmit for periods 
amounting to more than two hours a day. 

THE COST AND QUALITY OF RECEIVING 
APPARATUS 

SEVERAL companies are clothing their 
O broadcast receivers in extremely hand- 
some cabinets, advertised for sale at approxi- 
mately the same prices as equivalent American 
"furniture." Most of the less pretentious 
store sets, and also the separate parts, appear 
to be carefully and substantially made. Stores 
are full of apparatus for apparently every con- 
ceivable purpose, and, as at home, there are 
plenty of different kinds of instruments de- 
signed for the same purpose. The receiving 
apparatus of British amateurs, before the 
advent of broadcasting, was generally mounted 



*This of course, is not 
what we call "Morse" 
our land-line code but 
the "Continental" or 
"General Service" or 
"International Morse" 
code. 




A CORNER IN AN ENGLISH RADIO FACTORY 



196 



Radio Broadcast 




A SIX TUBE RECEIVER 

Three radio, carborundum detector, and three stages 
of audio made by Metropolitan-Nickers Company, 
of Manchester. It retails in England for 91 

on horizontal panels; this style still prevails in 
many cases, but slanting panels and vertical 
ones, similar to most of ours at home, have be- 
come much more popular during the last year. 
One or two manufacturers put out complete 
units in small square boxes, all the same size 
and each containing a condenser, or vario- 
coupler, or tube unit, or some other part. This 
arrangement is intended to appeal both to the 
person who wants to build up his set gradually, 
as his means allow, and to the novice-experi- 
menter, and the restless and ubiquitous 
"circuit-hound" whose chief pleasure is the 
pursuit of new and more efficient hook-ups. 
The square blocks thus serve their purpose. 
One objection may be that a mess of external 
wiring results from connecting up six or eight 
of these units. 

The cost of parts averages about the same as 
in the States, in spite of a considerable vari- 
ation in many items. Of course, the British 
listener is admittedly paying for his broadcast- 
ing; and those who buy store sets pay also a 



certain tax for the B. B. C. stamp required on 
all manufactured receivers. This tax varies 
from about i to 4 per cent, of the selling price 
of the apparatus. In some cases, due to the 
incorporation of certain patented apparatus in 
the sets, there is in addition a Marconi tax to 
pay. Often, therefore, a B. C. L. pays his 
broadcasting license fee, the price of the set, 
the B. B. C. tax, and the Marconi tax, before 
turning his attention to such trifles as tubes, 
phones, and batteries. 

Many manufacturers include the B. B. C. tax 
in their advertised selling price, and some 
prices are inclusive of everything but tubes or 
everything but tubes and batteries, for in- 
stance, it will be seen that, as with us, it is 
with few exceptions impossible to buy a receiv- 
ing set which may really be called complete- 
from A battery to antenna wire. British 
enthusiasts have been known to exercise their 
voices in well-modulated complaint of this 
latter condition. 

Various makes of dry-cell tubes are now 
becoming popular. One type draws .06 of an 
ampere at 2.5 volts. These low filament con- 
sumption tubes are known as "dull emitters." 

THE RADIO ENTHUSIAST HABITAT: 
EVERYWHERE 

I AM sure that there is no fundamental 
difference between members of the radio 
fraternity in America and in this, or any other 




AN EIGHT TUBE OUTFIT 

An excellent example of excellent English taste and work- 
manship in cabinet building. This set has five stages of 
tuned radio-frequency amplification, and two of audio 



England's Venture into Broadcasting 



197 




A GOOD ENGLISH AMATEUR RADIO INSTALLATION 
Is this station jCC at Bath 



country. One meets here the same enthusiasm 
the same exaggerations, the same patter of 
station calls, apparatus, and circuits; the same 
praise, the same "kicks," the same "wise 
cracks." It is only the words which expresses 
all this that differ. And the vocabulary of the 
British listener (not to mention the old-time 
amateur) must at first seem very foreign to 
any one trained in the American idiom. " Dull 
emitter valves," "frames," "accumulators," 
"note magnifiers," and other "components" 
are discussed on all sides. 

WHITHER? 

WHERE is it all going to lead?" is, of 
course, the question frequently asked. 
\\ hat will broadcasting be like in England five 



years from now or even two years?" Nobody 
can do more than guess at the answer; but the 
outlook is promising and mighty interesting. 

People here are interested in what the 
" Yanks" are planting and reaping in the radio 
field, but they are far from dropping their tools 
to gawk at us; they have far too much to do 
tilling their own wavelengths. A number of 
British amateurs, engineers, and the "general 
public" are expressing their hope, even their 
conviction, that reliable rebroadcasting of 
international programs is the next big thing 
we have to look forward to. 

And we can only express the same hope, and 
say to them (with double meaning): "More 
power to you!" 

More power to all of us! 



The Story of the Super-Heterodyne 

Its Origin, Development and Some Recent Im- 
provements A Radio Club of America Paper 

By EDWIN H. ARMSTRONG 

Marcrllm Hartley Research Laboratory, Columbia University, New York 





THE purpose of this paper is to de- 
scribe the development of the super- 
heterodyne receiver from a war-time 
invention, primarily intended for 
the exceedingly important radio tele- 
graphic direction finding service in the Signal 
Corps of the American Expeditionary Force, 
into a type of household broadcasting receiver, 
which, with our present vision, appears likely 
to become standard. 

The invention of the super-heterodyne dates 
back to the early part 
of 1918. The full 
technical details of 
this system were made 
public in the fall of 
1919. Since that time 
it has been widely 
used in experimental 
work and is responsi- 
ble for many of the 
recent accomplish- 
ments in long-distance 
reception from broad- 
casting stations. 
While the superiority 
of its performance over 
all other forms of re- 



ceivers was unques- 
tioned, very many 
difficulties rendered it 
unsuitable for use by 
the general public 
and confined it to the hands of engineers and 
skilled amateurs. Years of concentrated ef- 
fort from many different sources have pro- 
duced improvements in vacuum tubes, in 
transformer construction, and in the circuits 
of the super-heterodyne itself, with the result 
that early in the month of April there has 
been made available for the general public, a 
super-heterodyne receiver which meets the re- 
quirements of household use. 

It is a peculiar circumstance that this inven- 



Truth and Poetry Plus Romance 

No reader who makes a practice of neatly 
avoiding the "technical articles" should miss 
any of these fascinating lines of Edwin Arm- 
strong's straightforward story of the develop- 
ment of the super-heterodyne, which is quite 
decidedly romantic in spite of the simple and 
direct way in which it is told. 

This article tells how the second harmonic 
super-heterodyne was developed after the 
pressure of war-time necessity had caused 
the practical invention of the receiver. Mr. 
Armstrong has some pertinent remarks to 
make on radiation, reradiation, and the future 
of broadcast reception in general. 

Here is an article that no one genuinely 
interested in radio should fail to read. It is 
an article we are proud to publish. THE 
EDITOR. 



tion was a direct outgrowth of the failure of 
the vacuum tubes constructed in the United 
States to meet a very important problem con- 
fronting the American Expeditionary Force. 
This problem was the reception of extremely 
weak spark signals of frequencies varying from 
about 500,000 cycles to 3,000,000 cycles, with 
an absolute minimum of adjustments to enable 
rapid change of wavelength. The technical 
difficulties of this problem are now so well 
known that it is not necessary to consider them. 

H. J. Round in Eng- 
land, and Latour in 
France, by some of 
the most brilliant 
technical radio work 
carried out during the 
war, had produced 
substantially aperiodic 
radio-frequency am- 
plifiers covering the 
band from 500,000 to 
i ,200,000 cycles and 
though covering a 
much more limited 
band, amplifiers oper- 
ating on 2,000,000 
cycles had been con- 
structed. These re- 
sults had been accom- 
plished by the use of 
vacuum tubes and 
transformers of a min- 
imum capacity. As this apparatus was used in 
the highly important intelligence services, all 
information was carefully guarded. When the 
United States entered the war, the fact that it 
was necessary to produce extremely sensitive 
receivers for short wavelengths and that tube 
capacity would prove the bar to a straightfor- 
ward solution of the problem was not known in 
this country. As a result, no attention was 
paid to the capacity in the type of vacuum tube 
which was adopted and while the tube met the 




EDWIN H. ARMSTRONG 

And an early model of the six tube regenoflex second harmonic super-heterodyne one of the greatest achievements ever 
made in broadcast receivers. This young inventor at one time studied under Professor J. H. Morecroft at Columbia 
University, New York City. Much of his present radio experimental work is being done at the Marcellus Hartley 

Laboratory at Columbia 



Radio Broadcast 



3 Stages of Amplification 




To Audio 
Amplifier 



Oscillator 



FIG. I 

This is a simplified schematic diagram of the ordinary super-heterodyne with 
a separate oscillator, first detector, three stages of radio-frequency amplifi- 
cation and a second detector. The audio amplifier may be added as shown 



requirements of the lower frequencies ad- 
mirably, it was impossible to use it effectively 
for the frequencies of importance in the direc- 
tion finding service. 

HOW THE SUPER-HETERODYNE ORIGINATED 

DURING the early part of 1918, through 
the courtesy and energy of General Ferric 
and his staff, the American Expeditionary 
Force was supplied with apparatus of French 
manufacture. It was quite apparent, however, 
that this source of supply could not be a 
permanent one and a solution of the problem 
became essential. During the early part of 
1917, 1 had made a careful study of the hetero- 
dyne phenomena and their effect on the 
efficiency of rectification. With these experi- 
ments freshly in mind, the idea occurred to me 
to solve the problem by selecting some fre- 
quency which could be handled by the tubes 
available, building an effective amplifier for 
that frequency, and then transforming the in- 
coming high frequency to this readily amplifi- 
able value by some converting means which 
had no low limit; preferably the heterodyne and 
rectification. The principles and advantages 
of this method were explained in a paper pre- 
sented before this Institute and are now so well 
known that no further explanation is required 
here.- 

After much experimental work, an eight- 
tube set was constructed consisting of a recti- 
fier tube, a separate heterodyne oscillator, three 
intermediate-frequency amplifiers, a second 
rectifier or detector, and two audio-frequency 
stages. The intermediate-frequency stages 
were coupled by tuned air-core transformers 
set for a frequency of about 100,000 cycles, 
with an adjustment for controlling the regen- 
eration. The amplification of voltage measured 
at the input of the second detector with the 



amplifier just below the oscillating point, was 
about equivalent to a radio-frequency amplifi- 
cation of 5OO. 1 The arrangement of its cir- 
cuits in Fig. i gave satisfactory results except 
that the inclusion of a regenerative control 
on the intermediate-frequency amplifier made 
skilled handling necessary, as the adjustment 
of the frequency of the oscillator changed the 
plate current of the detector tube and this, in 
turn, varied the resistance which that tube 
introduced into the amplifier system and upset 
the regenerative adjustment. 

The Armistice ended development at this 
point, but in the fall of 1919, for the purpose 
of determining the results which could be ob- 
tained by pushing the super-heterodyne method 
of reception to the limit, a resistance-coupled 
intermediate-frequency amplifier consisting of 
five high mu tubes was constructed. The 
voltage amplification of these five stages was 
probably between 5,000 and 10,000 fold. 
While greater amplification could have been 
obtained, the sensitiveness of a set composed of 
a two-tube frequency converter, a five-tube 
intermediate-frequency amplifier, a detector, 
and one-stage of audio, was such that on a 
three-foot (one-meter) loop, the sole criterion 
of reception was simply whether the signal was 
stronger than the atmospheric disturbances. 

PAUL GODLEY USED A SUPHR-HE TERODYNE TO 
COPY AMERICAN AMATEURS IN SCOTLAND 

THE sensitiveness of the super-heterodyne 
was demonstrated during the winter of 
1919-1920 when the spark signals from ama- 
teur stations on the West coast and telephone 
signals from destroyers in Southern waters 

'This amplification is based on the ratio of the voltage 
applied to the second detector to the voltage at the loop 
terminals. The intermediate frequency amplification is 
unknown. 



The Story of the Super-Heterodyne 



201 




FIG. 2 

This super-heterodyne is transformer-coupled and has been 
used by Major Armstrong in many demonstrations 
given under the auspices of the Radio Club of America 



were received in the vicinity of New York on a 
three-foot (one-meter) loop. Probably the 
most striking demonstration of the capabilities 
of the method occurred in December, 1920, 
when Paul F. Godley, at Ardrossan, Scotland, 
received the signals of a large number of ama- 
teur stations located in the United States, many 
of them being spark stations. The super- 
heterodyne used by Godley consisted of a 
regenerative tube for the first rectifier, a separ- 
ate oscillator, four stages of resistance-coupled 
intermediate-frequency amplification, a second 
rectifier, and two stages of audio. While it is 
difficult to state definitely the actual voltage 
amplification obtained, it appears to have been 
between 3,000 and 5,000 fold. 1 

With the coming of broadcasting and with 
the great increase in the number of stations 
and the consequent interference, the super- 
heterodyne began to take on a new importance 
an importance which was based not on its 
superior sensitiveness nor on its selectivity, but 
on the great promise which the method offered 
in simplicity of operation. It 
was, and still is, the standard 
practice to furnish the public 
with receivers equipped with 
a variety of tuning adjust- 
ments for the purpose of 
amplifying the desired band 
of radio frequencies and ex- 
cluding all others. As a 
matter of fact, many more 
adjustments are on receivers 



than should be used more 
than could be placed in the 
hands of the average user. 
It would obviously be of the 
greatest importance if in 
some way these tuning ad- 
justments could all be made 
in the laboratory by skilled 
engineers and sealed, leaving 
some relatively simple adjust- 
ment for the hands of the 
operator. The super-hetero- 
dyne offered the ideal solu- 
tion. This solution lay in 
the construction of an 
intermediate-frequency am- 
plifier which would am- 
plify a given frequency and a band 5,000 
cycles above and below it and which would 
cut off sharply on either side of this desired 
band. The adjustments necessary to accom- 
plish this could all be made by skilled men, 
and the only, operations left for the user would 
be the two adjustments necessary to change 
the incoming frequencies down to the band of 
the amplifier adjustments which are not 
dependent on each other, which are of extreme 
simplicity, and which can be made equally 
well by the novice or the engineer. To deter- 
mine just what could be accomplished along 
these lines, the writer, working in conjunction 
with Mr. Harry Houck constructed during 
the spring of 1922, a set designed for the maxi- 
mum usable sensitiveness and selectivity. 

THE FIRST MODEL 

THE set-up consisted of one radio-frequency 
stage (non-tuned transformer) a rectifier 
tube, an oscillator tube (used as a separate 
heterodyne), a three-stage iron-core transform- 



(' Based on the standard previously 
described. This is without the 
second heterodyne which was used 
in receiving continuous waves.) 




FIG. 3 
This is the interior of the receiver pictured above 



2O2 



Radio Broadcast 



er-coupled intermediate-frequency amplifier 
designed to cover a band of 20,000 to 30,000 
cycles, a second detector tube, and two stages of 
audio-frequency amplification. UV-2O1-A tubes 



ToAmplifier 




Signal 



FIG. 5 

The fundamental circuit of the second harmonic 
method of producing the oscillator frequency 

were used. The set without the audio-fre- 
quency amplifiers is illustrated in Fig. 2 and 
Fig. 3. To prevent the intermediate-frequency 
amplifier from oscillating, each stage was 
shielded separately. The use of a radio-fre- 
quency stage ahead of the first detector pos- 
sesses a number of advantages but the chief 
one is in eliminating the reaction between the 
loop circuit and the oscillator circuit. Ex- 
perience with the original type had shown 
that when an oscillator of ordinary power was 
used, it was necessary to couple it rather 




FIG. 4 

The ordinary type of wave-changer for the 
super-heterodyne requires two tubes as shown 
here the new method is shown in Fig. 5 

closely with the loop circuit in order to insure 
a sufficiently strong heterodyning current. 
This close coupling affected the tuning of both 
circuits, an adjustment of one changing the 
setting of the other. To avoid this trouble 
and to produce a system wherein a station could 
always be tuned-in on exactly the same set- 
tings, a single stage of radio-frequency ampli- 



fication (using a non-tuned transformer) was 
used, and the oscillator was coupled into this 
transformer. This arrangement eliminated the 
reaction, reduced the radiation to a minimum, 
and, in addition, removed the damping of the 
first rectifier from the loop circuit and im- 
proved its selectivity. 

The results obtained with this set were about 
as expected. On a three-foot (one-meter) 
loop, the factor determining the reception of a 
station was solely whether the signal strength 
was above the level of the atmospherics. The 
selectivity was such that stations which had 
never been heard before on account of blanket- 
ing by local stations, were received without a 
trace of interference. While the performance 
of the set was much superior to any other 
receiver, it was apparent that the cost of con- 
struction and maintenance was prohibitive. 
The single item of a ten-ampere filament cur- 
rent will give some idea of the size of the 
storage battery and auxiliary apparatus required. 

With the coming of the low filament con- 
sumption, or dry battery type of tube, the 
possibilities of producing a super-heterodyne 
for household use were tremendously improved. 
The set of Fig. 3 was remodelled for the WD-i i 
tube and its sensitiveness was brought to about 
the same value as obtained with the storage 
battery tubes. This was a long step forward 
but still its cost was prohibitive. 

WHY THE SECOND HARMONIC PRINCIPLE WAS 
DEVELOPED 

IT HAD been apparent ever since the ques- 
tion of the application of the super-hetero- 
dyne to broadcasting had been considered, that 
there were too many tubes performing a single 
function which were quite capable of perform- 




age 



FIG. 6 

This circuit makes it possible to reflex some of the inter- 
mediate amplifier tubes, using them for audio amplifica- 
tion as well. The result is more economical operation 



The Story of the Super-Heterodyne 



203 



ing a double one. The most outstanding case 
is that of the separate heterodyne oscillator. 
In view of our knowledge of the self-heterodyne, 
it appears quite obvious to perform the first 
rectification by means of a self-heterodyne 
oscillator and thereby save a tube. As a 
matter of fact, this was one of the very first 
things tried in France, but, except for very 
short wavelengths, it was never very successful 
when a high intermediate frequency was 
necessary. The reason was this. If a single 
tuned oscillating circuit was used, the detun- 
ing to produce the proper beat caused a loss of 
signal strength which offset the gain of a tube. 
If two tuned circuits were used on the oscilla- 
tor, one tuned to the signaling frequency and 
the other arranged to oscillate at the hetero- 
dyning frequency, then on account of the rela- 
tively small percentage difference in frequency 
a change in the tuning of one circuit changed 
the tuning of the other. The solution of this 
problem was made by Houck, who proposed an 
arrangement so simple and so effective that 
it completely solved the problem. Houck 
proposed to connect two tuned circuits to the 





This is the interior of the original receiver 
built on the second harmonic principle 



FIG. 7 

A similar arrangement to that shown 
in Fig. 5 and explained in the text 

oscillator, a simple circuit tuned to the fre- 
quency of the incoming signal and a regenera- 
tive circuit adjusted to oscillate at such a 
frequency that the second harmonic of this fre- 
quency beating with the incoming frequency 
produced the desired intermediate frequency. 
The general arrangement is illustrated by Fig. 5. 
In this circuit A is tuned to the incoming 
signal, circuit B is tuned to one-half 
the incoming frequency plus or minus 
one-half the intermediate frequency, 
and the circuits C and D are both 
tuned to the intermediate frequency. 
The operation of the system is in 
line with ordinary self-heterodyne 
action. By reason of the asymetrical 
action of the tube, there are created 
in the circuits a variety of hanrupnics. 
The second harmonic combines to 
produce beats with the incoming 
signals of the desired intermediate 
frequency, the tube rectifies them to 
produce the desired intermediate 
frequency and, through C and D, 
the new frequency is supplied to the 
amplifier. On account of the fact 
that circuits A and B are tuned to 
frequencies differing by approxim- 
ately 100 per cent., a change in the 
tuning of one has no appreciable 
effect on the tuning of the other. 
This arrangement solved the oscillator 
problem and, in addition, practically 
eliminated radiation. 

The next step in the reduction of 
the number of tubes, was to make 
the radio-frequency amplifier per- 
form the function of amplifying 



Radio Broadcast 



intermediate-frequency as well. This can be 
done with none of. the difficulties inherent in 
audio-frequency amplification, as the very small 
amplitudes of voltage handled by the first tube 
precludes the possibility of the grid becoming 
positive with respect to the filament. The 
general arrangement of circuits for carrying this 
out is illustrated by Fig. 6. In this arrange- 
ment the signals received by the loop are am- 
plified at radio-frequency by the first tube and 
applied to the grid of a second harmonic oscilla- 
tor byj means of an untuned radio-frequency 
transformer. The combined signaling and 
heterodyning currents are then rectified by 
the second tube producing a current of the 
intermediate-frequency which is applied to the 
grid of the first tube, amplified therein and 
passed on to the second stage ! of the intermedi- 
ate-frequency amplifier. A more practical 
method of carrying out this idea is illustrated 
in Fig. 7. In this arrangement, a secondary 





Fig. 8 

In this five tube layout a loud 

'-peaker has been incorporated 



One of the early models of the six-tube receiver. 
The receivers now sold employ a similar circuit 

of the first intermediate-frequency transformer 
is connected to the grid of the first tube and in 
parallel with the loop circuit. Otherwise, the 
arrangements of Figs. 6 and 7 are identical. 
The parallel type of circuit arrangement elimi- 
nates a variety of reactions which would give 
rise to oscillations of various frequencies and in 
addition, prevents the reception of long-wave 
signals by the intermediate-frequency ampli- 
fier. When this development had been com- 
pleted, improvements in the design of the 
intermediate-frequency transformers made it 
possible to obtain with two stages all the am- 
plification which could be used. 

On account of the high amplification, signals 
from local stations overload the second recti- 
fier and introduce distortion. Control of the 
amount of intermediate-frequency amplifica- 
tion is essential. While there are numerous 
methods equally effective, the simplest one 
appears to be the control by means of the 
filament temperature of the second intermedi- 
ate-frequency amplifier. 1 

The features just described were all incor- 
porated in the receiver which is illustrated in 
Figs. Sand 9. The set measured 16" x 10" x 
10" and was completely self-contained the 
batteries, loop antenna, and speaker mechan- 
ism being enclosed in the box. The results 
were highly satisfactory and loud speaker 
signals (at night) in the vicinity of New York 
were obtained from stations in Chicago and 
Atlanta. It demonstrated that not only could 
a household receiver of the super-heterodyne 

'Although some form of potentiometer type of control of 
the voltage applied to the grid of one of the amplifier tubes 
would obviously be better, the simplicity of the filament 
control has many advantages in manufacture. 



The Story of the Super-Heterodyne 



205 




FIG. 9 

Interior of the super-heterodyne portable with 
which an inexperienced woman heard 2LO 
during the tests run by RADIO BROADCAST and 
the Wireless H'orlJ (London) last November 

type be built, but that the first practical solu- 
tion of the portable set was at hand. 

FROM THE LABORATORY MODEL TO THE COM- 
MERCIAL PRODUCT 

IN THIS form, the capabilities of the set were 
brought to the attention of the Westing- 
house Electric and Manufacturing Company 
and the Radio Corporation of America a little 
over a year ago. 1 ts possibilities were instantly 
visualized by Mr. David Sarnoff, who immedi- 
ately took steps to concentrate the resources 
of the research laboratories of the Radio Cor- 
poration of America, the Westinghouse Electric 
and Manufacturing Com- 
pany and the General Elec- 
tric Company on this new 
development. From that 
point on it passed into a 
new phase that of placing 
an invention in a commer- 
cial form. In the limited 
time available, this was a 
most extraordinarily diffi- 
cult proposition, and credit 
for its accomplishment is 
due to the untiring efforts 
on the part of the engineers 



of the above organizations. Many improve- 
ments and some radically new ideas of design 
have been introduced, but it is the privilege of 
those responsible for them to present these. 
In the final development of this receiver, an ad- 
ditional stage of audio-frequency amplification 
was added in order to insure operation within 
steel buildings, particularly those within the 
city limits where signals are relatively very weak 
compared to suburban locations. This makes 
a six-tube set but six tubes can be readily 
operated on dry batteries and the increase in 
sensitiveness is well worth the extra tube. 

Some idea of the sensitiveness and the ease 
of operation of the set illustrated in Fig 9, 
may be gathered from an incident during the 
RADIO BROADCAST Wireless World trans- 
atlantic broadcasting tests of November and 
December, 1923. On December ist, two 
women, neither having any technical radio 
knowledge, received loud speaker signals from 
station 2LO, London, England. This was 
accomplished at Merrimac, Massachusetts, 
with the set and loop illustrated in Fig. 9 
and perhaps constitutes a record for the first 
radiophone reception from Europe with a 
portable receiver. With the same set and a 
three-foot (one-meter) loop, loud speaker 
signals from broadcast stations on the Pacific 
Coast were received in the vicinity of New 
York on an average of three or four times a 
week. The sole criterion of reception was 
whether the signal strength was above the 
level of the atmospheric 
disturbances. 

The type of super- 
heterodyne described here- 
in is now available to 
the public in the two 
forms illustrated in 
Fi^s. loand n. Each of 




FIG. 10 

The semi-portable six tube super-heterodyne now coming into 
great popularity. It is luxurious in appearance, simple to oper- 
ate and produces excellent volume with marked clearness of tone 



2O6 



Radio Broadcast 




FIG. I 1 

The loud-speaker has been made a part of the 
receiver and a rotatable loop is provided in 
the case below. This receiver is one of the 
most luxurious ever placed on the market 

these sets incorporate the arrangements herein 
described. Their sensitiveness is such that, 
with a two-foot loop and an unshielded location, 
the atmospheric disturbances are the criterion 
of reception. Here we reach a milestone in 
the development of broadcast receivers for no 
increase in the distance of reception can now 
be obtained by increase in the sensitiveness of 
the receiver. Unless the power of transmitting 
stations is increased we are about at the limit of 
the distance which can be covered. Future 
improvement of this receiver will lie along the 
line of increasing its selectivity and simplifying 
its construction. Aside from the development 
of the super-heterodyne but few recent radio 
receivers have improved in other than their 
mechanical arrangement and cabinet work. 



APPENDIX 

Some notes on the interaction between 
receiving sets. Radiation Coupling be- 
tween antennas Have broadcast sta- 
tions enough power to go around? 



PROBABLY the greatest outstanding 
problem in radio [is the interaction be- 
tween receiving sets. This interaction 
is due to several causes. The three main types 
may be classed under the heading " Radiation, 
Reradiation, and Coupling between Antennas." 
At the present moment, much attention is 
focused upon the problem of radiating re- 
ceivers. Much is being written about it under 
the misnomer " Reradiating receivers." Little 
has been written on the subject of reradiating 
receivers and still less about the problem re- 
sulting from the coupling between antennas. 
Doubtless this is due to the fact that the last 
two problems are at present masked by the 
first one. In my opinion, they are equally 
important, will cause increasing trouble and if 
radio proceeds along its present lines of develop- 
ment, will as seriously affect long distance re- 
ception as radiating receivers are affecting it 
at the present time. 

To explain the above three types of inter- 
ference, I will define each of them: 

RADIATION 

THIS interference is produced by sets 
which, of their own volition, generate 
electrical oscillations of a frequency which is 
determined by the constants of their own cir- 
cuits. The effect on neighboring receivers is 
the production of a beat note or whistle on 
wavelengths close to the frequency radiated 
by the oscillating receiver. This type of in- 
terference is commonly and improperly called 
" Reradiation." A radiating set may also 
produce interference by reradiation but this is 
a secondary matter and the primary cause of 
interference is radiation. The radiation is in 
the form of a continuous unmodulated wave. 

RERADIATION 

THIS type of interference results from an 
antenna picking up energy from an in- 
coming wave and as the name implies, reradiat- 
ing that energy into space. The reradiated 



The Story of the Super-Heterodyne 



207 



energy is not a continuous unmodulated wave 
as in the previous case but a wave which is 
modulated substantially in accordance with the 
modulations of the received signals and which 
exists only as long as the received wave exists. 
This type of interference is most pronounced in 
the case of regenerative receivers which are set 
just below the point of oscillation. It causes 
trouble in near-by receivers in two ways. One 
is that the energy reradiated is not in the 
form in which it was originally transmitted 
from the sending station but has some of the 
characteristics of the receiving set superim- 
posed upon it. The other is that the reradiated 
energy, particularly in the case of a large an- 
tenna with regeneration, boosts the signals in 
adjacent antennae, producing a fictitious signal 
strength in the other receivers which disap- 
pears when the large antenna is tuned to an- 
other station. 

At present, receivers which regenerate in the 
antenna are responsible for most of the trouble. 
Elimination of regeneration in the antenna 
would aid the situation greatly. It would not, 
however, be a permanent solution of the pro- 
blem. The elimination of regeneration in the an- 
tenna would merely reduce the area over which 
the effect of reradiation would be felt. If the 
number of antennae increase at the present 
rate, it will not be long before practically 
every antenna in a city will be within the 
reradiating range of a dozen others, each of 
which will make its influence felt. If regener- 
ation is eliminated from all the antennae, 
then the question of whether the signal will be 
strengthened or weakened in any individual 
antenna on account of the proximity of 
the others, will depend largely upon their 
relative size, resistance and position. In 
general, a small antenna in the proximity 
of a large one will have its signals strengthened 
when the large antenna is tuned to the same 
wave, although this rule is not invariable. 

COUPLING BETWEEN ANTENNAE 

THIS type of interference is perhaps the 
most annoying of all. It occurs where 
two or more antennae are located so close to- 
gether that each affects the tuning of the other. 
Where several antennae are associated to- 
gether and produce this effect (for example, 
when they are all on the same roof) the diffi- 
culties of the operator in keeping his set in 



tune with a particular station can well be 
imagined. 

At the present time in congested localities, 
all three of these types of interference occur 
and the solution of the radiation problem, while 
it is technically and economically possible of 
solution, will but serve to concentrate atten- 
tion upon two other problems which are not 
technically capable of solution. In addition 
to these specific problems, we have in cities 
the much broader one of whether there is 
going to be enough energy to go around. It is 
perfectly apparent at the present time that the 
tuning of a large number of receivers in a con- 
gested area to the same signal results in a 
weakened signal for practically everybody. If 
every housetop were fitted with several an- 
tennae, the question arises as to how much 
energy the man in the center of the city would 
find left if everyone ahead of him had absorbed 
as much from the wave as possible by using as 
high and efficient an antenna as he could erect. 
The sole solution to this and all the other 
troubles is the use of an antenna of the loop type 
whose effect on near by receiving stations is 
negligible. 

Of course, this necessitates more sensitive 
receivers with an increase in amplifying power 
commensurate with the relative receptive pow- 
ers of an antenna versus a loop. At first sight, 
it might appear that the cost of this change 
would be prohibitive but with our present rate 
of development, I believe that it is going to be 
possible to build loop sets as sensitive as our 
present type antenna sets with but relatively 
little increase in cost. At the same time, the 
situation can be improved from another angle. 
The power of transmitting sets will gradually 
increase both because of the fact that there is 
no way to eliminate the effects of atmospheric 
disturbances, elevator induction, X-ray ma- 
chines and all the other types of interference 
which exist in a large city except to ride over 
them with high power and because of the 
fact that from the program standpoint, it is 
economically better to concentrate talent at 
one point. 

All these factors point to the elimination of 
the present type of antenna which will disap- 
pear in the same manner as the overhead 
telegraph, telephone, electric light and trolley 
wires have disappeared in the last twenty 
years. 







. 



The Jsteners' _ ^fbintof View 

BA/ X^_> --.. vjflH rak. x\ ..-" --, 





Radio Talent Is Klot Localized 



A" 3NG the many advantages made 
possible through radio, an outstand- 
ing feature is the opportunity it 
affords each section of the country 
to gain an understanding of the 
local musical talent in all the other sections. 
Even to those of us who, through much travel 
to various music centers while carrying on 
our professional activities, have felt that we 
were well in touch with the musical life of the 
country, the radio brings constant revelation, 
as surprising as it is agreeable. 

Before the days of broadcasting we would 
one and all have said that the best local musical 
talent would be found in those localities where 
music, as a profession, had the greatest follow- 
ing. But that uncanny medium of communi- 
cation, the microphone, is apt to prove this 
conclusion more often wrong than right. Some 
of the best singing and piano playing the 
present writer has heard over the radio goes 
to the credit of such stations as WOC at 
Davenport, and WHAA, Iowa City, Iowa; 
KFKX, at Hastings and WOAW at Omaha, 
Nebraska; W MA B, Oklahoma; WCAL, North- 
field, Minnesota, to name but a few. This 
does not mean that you will always get satis- 
factory musical programs through these sta- 
tions; but if you tune them in often enough 
you will at one time or another hear some of 
the most gratifying performances the radio 
has to offer. 

Why is this? Perhaps some of our readers 
can enlighten us. It is a case where many 
opinions are worth more than one. As for a 
single opinion, the answer to the question 



seems two-fold, First, that in such towns as 
these, and many others as well, good health 
pervades the musical life. Good health in 
that the bitterness of unrelenting competition 
has not eaten to the heart of that life and made 
it a struggle for existence against almost super- 
human odds. And another reason may be 
that many women who once expected to pur- 
sue music as a profession and studied under 
noted teachers to this end, gave up the fight, 
married, settled in these communities and are 
now using their music as a by-product instead 
of making it the main interest of their lives. 
Also among the men may be some who might 
have become professional singers, but who at 
the crucial moment decided to make their lives 
financially sure by becoming established in 
business and who now use their vocal accom- 
plishments as church singers and through con- 
cert appearances in near-by localities. 

The colleges scattered through these sec- 
tions also contribute their share toward the 
musicians who are heard on these programs, 
and an occasional station may be found that 
is directly associated with a college. But even 
in such cases the programs are not confined to 
the students or the faculty. 

Long before such a thing as broadcasting 
was dreamed of, many of these towns now 
sending out at times such excellent radio 
programs were known among musical mana- 
gers as lucrative fields for concert artists. But 
patronizing a dozen concerts or so during a 
season has little effect on the musical culture of 
a community as compared with the residence in 
that community of well trained musicians. 




BETTY COMPTON 

In "Vogues." What has become of the inventor who said he would make it possible to see a broadcast performance 

as well as hear it? Doesn't this picture prove that his invention was badly needed when WJZ broadcast the musical 

revue, "Vogues," from start to finish direct from the Schubert Theatre? 



210 



Radio Broadcast 



The fact that many such musicians live in the 
localities distant from the so-called music 
centers can be proved time and again by one 
who uses a receiving set. 

And just as this was being written came a 
letter from a friend who was long a resident of 
New York City where she continually heard 
the best that that city had to offer in music, and 
who is now in a South Dakota town so small 
you cannot find it on 
the map. She writes: 

" I have heard some 
really good music here. 
It is interesting to find 
real gifts and talent 
tucked away in such 
secluded places as this." 

Doesn't this com- 
ment prove that if this 
little town had a broad- 
ca sting station some 
music worth the hearing 
could be programmed? 

While the towns pre- 
viously mentioned are 
by no means secluded 
places, but on the con- 
trary are known far and 
wide, it has taken the 
radio to bring their 
musicians into public 
knowledge. If the an- 
nouncers at these sta- 
tions would be some- 
what more particular in 
giving the names of the 
various persons heard 
quite a list of those 
who have been enjoyed 
could be set down here, 
stance, want to write Pauley for Crosby, in case 
the name of the woman pianist who recently 
played so well in Hastings, Nebraska, should be 
Crosby although it sounded like Pauley. . . . 
So let the list remain unwritten. 

After all, every disadvantage has its com- 
panion advantage. We have all considered it 
a disadvantage that money was not available 
for the payment of radio music so that the 
regular concert artists might be heard by every 
listener, and this must in time come to pass. 
But had such a custom prevailed from the 
beginning of broadcasting, we should never 
have known what fine local talent is to be 
found in many towns. 



Talented Youth Is Broadcasting 



Ti 




RUTH EDWARDS 

Pianist. Miss Edwards has been heard a number of 
times over the radio as pianist of the Cleveland Institute 
of Music Trio. These players, also the String Quartet 
from the same school, have provided one of the most 
artistic features associated with station \VTAM 



One does not, for in- 



HE monthly concert given by the Rens- 
selaer Polytechnic Institute Students 
Symphony Orchestra at Troy, N. Y., 
Station WHAZ, always has something good to 
offer, and, apart from this, is interesting 
in that it is a means of making known what 
good work some of our young people are doing 
along musical lines. 

One would expect 
these students to play 
popular music well, as 
it is an expression of 
youth's spirit. But for 
them to give a good per- 
formance of such a work 
as a Ballet Suite by 
Delibes is a test of gen- 
uine musical under- 
standing; for it takes 
something more than 
mere love of music to 
bring out with any de- 
gree of satisfaction the 
fascinating grace and 
polish of this French 
composer. They gen- 
erally include a move- 
ment from some classic 
symphony in their pro- 
grams, on one occasion 
giving the first move- 
ment from Haydn's 
"Military Symphony." 
And they will even play 
for you a Strauss waltz 
in a way that would do 
credit to a more preten- 
tious organization. The conductor, A. Olin 
Niles, must be a man of ideals as well as ability. 
May he long keep up his good work! 

Another student organization, quite famous 
in its own locality, the Lincoln High School 
orchestra of Jersey City, was recently heard 
through Station WEAF under the baton of 
C. W. Barget. These players, forty-one boys 
and four girls, range in age from ten to fifteen 
years. Probably the reason there are so few 
girls in the personnel is because ninety-nine 
girls out of a hundred who study music study 
the piano. 

This High School orchestra is an organization 
of which Jersey City may well be proud, both 
because of the talent of the players and the 



The Listeners' Point of View 



21 I 



way that talent has been drilled by Mr.Barget. 
But it is open to the criticism that applies to 
all of our public school orchestras, a prepon- 
derance of strings and the lack of certain in- 
struments imperative to the right performance 
of orchestral music. If fewer boys would 
study the violin and more would study wood 
wind instruments, or the French horn, the tuba, 
the double bass, our school orchestras would 
be improved, and the boys themselves would be 
benefited because they would stand a better 
chance of using their musical education for 
financial returns if they so desired. For you 
can find hundreds of good violin players these 
days to one man who can play, let us say, the 
bassoon, the oboe, the French or English horn. 

And while on the subject of young people, 
those boys from the North East Y. M. C. A. 
Minstrel Troupe who took part in a program 
broadcast from station WTAM, Cleveland, 
gave their listeners a jolly good time with 
their lively choruses and solos. Whoever 
drilled them did his work well. A program of 
this kind is a relief from the monotony of 
jazz when something popular is the object of 
the program maker. Jazz is all right some 
of it but there are other forms of popular 
entertainment the public enjoys as much if 
not more. 

As for jazz, it comes in fifty-nine varieties 
via radio. If you have in times past tuned-in 
WEAF Thursday or Saturday evenings at eleven 
o'clock and heard Vincent Lopez and his 
orchestra playing in the Hotel Pennsylvania 
Grill, unless you had the soul of a sluggard 
you did not tune out until the last note of the 
hour's program was sounded. And this is said 
by one to whom ordinary jazz is an abomina- 
tion. Fundamentally, jazz is an interesting 
musical medium, but, like all musical mediums, 
it must be handled with intelligence and finesse. 
Vincent Lopez brings both of these factors to 
the direction of his orchestra. Their playing 
showed that their guiding spirit was an artist. 

Yes, Mr. Lopez, we say this even though 
you do drop into the commonplace some- 
times. Why jazz portions of the ballet and 
the grand march from "Aida"? We heard 
those travesties hundreds of miles distant from 
New York the other night. 



The St. Louis Symphony Afield 

WHEN listening to the program of a 
public concert that is broadcast, the 
reaction of the audience is about as 
interesting a feature of the entertainment as is 
the performance itself. When the St. Louis 
Symphony orchestra, conducted by Rudolph 
Ganz, gave a concert in Jefferson City, Missouri, 
during a recent tour, it was broadcast through 
WOS. The response of the audience to every 
number showed that orchestral music does not 
go unappreciated in that rather small city. 
There was something like pandemonium after 
the "Tannhauser" overture, and another 
Wagner number, " Dich Theure Halle," given 
by the soloist, came in for the same sort of re- 
ception. When the announcer gave out the 
information that Mr. Ganz would play a re- 
quest number at the close of the program there 
was some curiosity on the part of one listener 
as to just what sort of music would be re- 
quested. It proved to be " The Blue Danube." 
Not a bad choice, by any means. 

The management of the St. Louis orchestra 
evidently has no fear of a broadcast perfor- 




EDWARD GERMAN'S "Three Dances 
from the Music to Henry VIII," heard 
from nine different stations in one evening, 
shows that good music can be popular music. 



HENRY HADLEY 

Composer, Conductor. Some of the lighter orches- 
tral works of this foremost among American composers 
are heard now and then over the radio from broadcast 
orchestras that make it a point to present programs of 
genuine musical value. While giving the major portion 
of his time to composing, Mr. Hadley is also well known 
as an orchestra director, having for some years been 
assistant conductor of the New York Philharmonc 



212 



Radio Broadcast 



mance injuring the patronage of the organiza- 
tion. On this tour the orchestra played in 
many Missouri towns that could listen in to 
that Jefferson City concert. They no doubt 
did listen, and then, early the next morning, 
bought seats for the coming concert in their 
town. That is what radio is going to do for 
the patronage of music, all over the country, 
just as soon as some of the musical managers 
get over their scare about it. 

Handel and Mendelssohn Are Still Popular 

A~TER the Madrigal Choir from the 
Oratorio Society of New York had 
sung choruses from "The Messiah" 
and "Elijah" through station WEAF, the an- 
nouncer asked those who had been listening to 
send in word if the program was enjoyed so that 
it might be known whether or not such pro- 
grams would be acceptable in the future. 

He could have found the answer to his ques- 
tion in any musical dictionary. Handel, 
who wrote "The Messiah," died in 1759. 
Mendelssohn, who wrote "Elijah," died in 
1847. Why have their works survived so 
long after their death? Because of the pub- 
lic's interest in them. 





CAPTAIN HERMANN WEBEL, U. S. A. 

Bandmaster. The 17th U. S. Infantry. His band 
has been heard from WOAW, and is very highly regarded 



VICTOR KOLAR 

Assistant Conductor of The Detroit Symphony Or- 
chestra. Mr. Kolar conducted the series of concerts 
for children given in Orchestra Hall, Detroit, during the 
past music season and broadcast from station WWJ. 
Thousands of children and grown-ups as well, far distant 
from Detroit, listened in to these concerts. Mr. Kolar 
in addition to being a conductor of conspicuous merit, 
is a composer whose works have attracted wide attention 

And so, Mr. Announcer at WEAF, the surety 
goes without asking, that many listeners were 
grateful to your station for giving them an 
opportunity to hear excerpts from these works. 

Flying Fists and the Microphone 

HAVING commented a number of times 
in this department on the programs 
of old-time American songs which are 
so deservedly popular with radio audiences, 
WBZ was tuned-in a while ago for the express 
purpose of hearing such a program which had 
been previously advertised. Immediately the 
dials were adjusted came a deafening roar of 
shouts accompanied by the stamping of feet. 
Then a voice: 

" If this broadcast is a flop you may know 
it's because I'm new to the job and there are 
seventeen people hanging on my back." 

The astonished listener-in examined the 
dials carefully. Surely there was a mistake. 
This could not be the Springfield station, al- 
ways so correct and courteous. Then came 



The Listeners' Point of View 



213 



another voice, the cultured sort that is ever in 
evidence from WBZ. 

"This is station WBZ broadcasting from 
Boston the fight at the Boston arena for the 
heavyweight championship of New England." 

The microphone was then turned over to the 
first voice, and from that moment until the end 
of the fight in the seventh round when Jack 
Shawkey knocked out Eddy Somebody (the 
listener was too excited to get his full name), 
radio music was forgotten by the one whose 
business it is to listen to it, for she has always 
had a secret longing to attend a prize fight. 
Round by round that fight was followed with 
many a chuckle over the drawling witticisms of 
the man at the microphone. If a galaxy of the 
greatest musical artists in the world had been 
broadcasting a program while that fight was 
in progress the dials would still have been kept 
at WBZ. Woman-like, the listener was root- 
ing for Eddy Somebody from the moment it 
became evident that he was getting the worst 
of it. And there was exultation 
that it took seven rounds for the 
challenged champion to retain his 
title. 

When it was all over and the two 
combatants, according to the man 
at the microphone, were "going 
home to mother," the WBZ cultured 
voice conveyed the information: 

" We will now resume our musical 
program from the Hotel Brunswick 
Studio, Boston." 

But, not being in a musical mood, 
with one's mind still bearing that 
graphic picture of the prize fight, it 
was not until some evenings later 
that a connection was made with the 
Hotel Brunswick Studio, Boston, 
where a program by the Tschaikow- 
sky String Quartet of the Weltman 
Conservatory of Music, Maiden, 
Mass., was the attraction. The ad- 
vance notice of this program had 
spoken of the quartet as being com- 
prised of four men " who have heard, 
studied and played the greatest mu- 
sic under the greatest conductors 
and with the greatest players, and 
who follow music as an art and not 
as a trade." 

This seemed, like many press no- 
tices, too good to be true. But the 
work of the quartet that evening 



did much toward justifying the preliminary 
praise. Even in the most brilliant numbers 
there was the poise that comes only after 
one has so thoroughly mastered the classics 
that something of their equable spirit will 
tincture the performance of the most modern 
works, just as it is the technical foundation 
of these works. Mr. Leon Weltman, with 
Edward Garmant at the piano, played a group 
of violin solos in a manner in keeping with 
the general high standard of the program 
which was one that did credit to station WBZ. 
All who heard this program must have elt 
grateful for the opportunity to enjoy such 
music so well presented. The entire program 
came through the air to the present writer's 
studio in Toledo as clearly as if it were heard 
in Boston. 

And it is frankly acknowledged we are 
glad that the prize fight came through just 
as clearly, but the thrill of hearing such an 
event involves considerable mental strain. 




MARY ELLIS 

Soprano. After being a member of the Metropolitan Opera Com- 
pany for a number of seasons, Miss Ellis has joined the ranks of oper- 
etta. Station WJZ has presented this young singer in a series of 
recitals of songs by Rudolph Friml with the composer as accompanist 



214 



Radio Broadcast 



Among Other Things 

Some of the other events that deserve being 
remembered, and one or two that should be 
forgotten are 

MRS. H. H. A. BEACH, America's foremost 
woman composer, in a short piano recital, 
Station WRC, Washington, D. C. An at- 
tractive group of n.umbers very charmingly 
played. 

MR. MORRIS A. SCOTT singinga group of 
songs, station WTAM, Cleveland, along 
about 1.40, A. M. He deserves special men- 
tion because he kept the tempo of every song up 
to the mark, and also because his phrasing was 
intelligent, his tone unforced, and his inter- 
pretations as a whole in good taste. 

THE iyth U. S. Infantry Band, stationed 
at Fort Creek, Nebraska, and frequently 
heard through station WOAW at Omaha. 
One of the finest bands in the country, judging 



from these radio performances. The playing of 
the men shows the broad musical education 
of the bandmaster, Hermann Webel, graduate 
of the Paris Conservatory, and later a student 
in musical history, theory, and composition, 
under leading New York teachers including 
W. S. Pratt and Henry E. Krehbiel. 



TH E program of old hymns the good ones 
sung Sunday evenings at station WHAA. 
Enjoyed perhaps by more people than the 
directors of this station realize. A custom 
that should be indefinitely continued. 



THE orchestra of the Hotel Statler, Cleve- 
land, in a dinner hour program each even- 
ing, broadcast by station WTAM. One of 
the finest hotel orchestras so far heard over 
the radio. The director gives his audience 
credit for enough good taste to enjoy some- 
thing other than jazz. His orchestra plays 
the lighter classics beautifully 




II 



Hi H _ ft*. . a m 

"'""iiiiHiiii HUH 



VINCENT LOPEZ 

And his well-known and well-liked orchestra playing at the 
Hotel Pennsylvania, New York, have been heard from WEAF 




RADIO FARTHEST SOUTH IN THE UNITED STATES 
Lazy Gulf of Mexico clouds and the tall towers of the Navy's high power radio station, NAR, at Key West, Florida 



THE MARCH OF RADIO 




President, Institute of Radio Engineers 



Names And Still More Names 



WAS there ever an art which 
called forth as many unpro- 
nounceable and unintelligible 
names as has radio? This 
failing for coining names, 
sometimes simple and sometimes complex, for 
tubes and circuits originated at a certain labor- 
atory in Schenectady about twelve years ago 
according to our recollection. These Graeco- 
Schenectady names, as Doctor DeForest aptly 
characterized them at the time, were not as 
bad as they first sounded because they were 
at least coined by men who knew some phil- 
ology. The names of sets and circuits which 
descend to-day on a startled world, surpass 
one's powers of pronunciation and analysis alike. 
One firm kindly condescends to translate its 
names into ordinary English for us, so we at 



least know what the names are intended to 
convey but many others remain outside our 
vocabulary and in despair we have decided not 
to attempt to keep 'up longer with the word 
coiners. 

That prefix "super" has suffered rare pun- 
ishment since radio came into its stride 
overworked so much that nowadays unless a 
set is super something or other no one pays 
any attention to it. And the situation has its 
serious side, as well as comic; many times lately 
we have been asked by enthusiastic newcomers 
in the radio field about the relative merits of 
the super-diddle-daddle and the super-daddle- 
diddle and have had to confess that we didn't 
even know what they were. Wherewith our 
reputation has straightway fallen to less than 
nothing! "He knows the theory," say our in- 



2IG 



Radio Broadcast 




CAPTAIN O. P. JACKSON, U. S. N. 

New director of Naval Communications. " I consider," 

says Captain Jackson, "that the greatest progress in the 

efficiency in our battle fleet will come about through the 

development of radio communication" 

quirers, "but he doesn't know how it is ap- 
plied." Won't the word coiners take a few 
days off? 

Pot Shots at the Goose, Golden Egg, et al. 

WHY can't some dealers see past the 
end of their noses? Several times 
in these columns we have noted the 
disagreeable effect produced by a raucous blast 
of what passes for music bellowed forth from 
a poor loud speaker, being pushed much past 
its working limit by excessive 
amplification. On our way to the 
ferry almost every evening we 
have to witness this misdirected 
effort of small dealers to get 
customers. A hole cut through 
the transom permits the loud 
speaker to pour forth its strident 
tones on the stream of commuters 
on their way home. The dealer 
evidently expects to attract cus- 
tomers by this display of the wond- 
ers of radio. Killing the goose 
that lays the golden egg is a 
sound economic policy compared 
to this disagreeable form of ad- 
vertising because at least the goose 
might be despatched noiselessly 
without bothering the neighbors. 



The average loud speaker is none too good 
even when treated gently, but when it is forced 
to compete with honking automobiles, and 
horse-drawn trucks on cobble-stone pavements, 
the effect is painful indeed. When will these 
dealers come to their senses and try to get good 
reproduction inside their stores, instead of 
making themselves a public nuisance and killing 
their trade at the same time? 

Something the Senate Can't Investigate 

RECENTLY the Senate considered a bill 
having to do with the conditions under 
which a broadcasting license could be 
held. This bill contains the declaration that 
"The ether and the use thereof within the ter- 
ritorial jurisdiction of the United States is 
hereby re-affirmed to be the inalienable pos- 
session of the people of the United States and 
their Government." 

Some of the Senators actually became curious 
as to the meaning of the bill they were acting 
upon and called upon the framer of the bill, 
Senator Howell of Nebraska, for a definition 
and explanation of the "ether." To this very 
pertiment inquiry (for surely our Senators 
wouldn't legislate on matters they didn't under- 
stand) Senator Howell confessed "We don't 
know much about the ether. We haven't been 
able to investigate it." 

Senator Bruce expressed the opinion that it 
was not seemly to assert ownership of some- 
thing which could not be defined or caught hold 
of, but the Senate disagreed with him and 
accepted the dictum of the bill that the people 
of the United States own the ether, inalienably. 




THE DEALER: "WHY is BUSINESS so POOR?" 



The March of Radio 



217 



It is perhaps a good thing that Mr. Doheny 
can't extract oil from the ether or the people 
probably wouldn't own it very long, in spite of 
the Senate's declaration to the contrary. 

An " R. E." is a Prophet Without Honor 

CTELY we have received several letters from 
men in the radio business on stationery 
burdened with such a name and title as 
John Smith, R. E., the R. E. evidently standing 
for Radio Engineer. As such a designation un- 
doubtedly gives prestige among people not 
acquainted with college degrees and their 
significance, it seems worth while to point out 
the status of such a degree. 

To the best of our knowledge none of the 
good technical schools in this country confer 
such a degree, and it does not seem likely 
that it will be officially recognized by any 
such school. The really technical phases of 
radio are electrical. Perhaps we had better 
not say simple because the theory of radio is as 
advanced as any other branch of electrical 
science. What we mean is that any one who 
wants to become a radio engineer must be 
first an electrical engineer, and a good one. 

The degree E. E. standing for electrical 
engineer is given by many engineering schools. 
None of them, however, have thought it wise to 
give such degrees as P. E. (Power Engineer) 
cr T. E. (Telephone Engineer) both of which 
branches of the electrical art absorb many more 
men and have much greater invested capital 
than radio. Such degrees would be of no ser- 
vice at all to the men using them because those 
with whom they associate would know enough 
immediately to appraise the standing of the 
user. The man using the title R. E. however, 
generally moves among people who may be 
unduly impressed with its importance. The 
title R. E. has no standing, and it is not difficult 
to maT<e the same assumption for those who 
affect it. 

There Are No "Inaudible" Radio Waves 

NEW ideas and developments in radio are 
coming to the front in such profusion 
that many times a writer finds himself 
without suitable language to express his 
thoughts. There are, of course, innumerable 
new words coined in the name of radio to 
designate new sets and circuits, or catch-words 
originated bv enthusiastic advertisers to get the 




Underwood iv Underwood 

WALLACE IRWIN 

The creator of HashimuraTogo, \vho makes that de- 
lightfully ingenuous, yet observing character say (in More 
Letters oj a Japanese Schoolboy): 



"On Table befront of him sat one black suitcase all 
covered with nickel plated science. It contained a 
window with electric bulbs doing so inside. It con- 
tained silver pushers, pullers, arrows and Kodak 
supplies. It contained so many Wires ibat I was sure 
it was connected with Edison somewhere. It bad a 
Horn with its mouth wide open as if to speak. It 
had one of these switchboards which enable Hon. 
Telephone Operatress to get your number wrong 13 
times out of 1 1 . Taken altogether, this was a Radio." 



purchaser's attention, but to these we do not 
refer. 

In a recent interview dealing with the re- 
markable scheme of radio repeating which the 
Westinghouse engineers are developing, one of 
them referred to their high frequency wave as 
"inaudible." "Pittsburgh," said he, "sends 
out the ordinary wave to which KDKA's 
listeners are accustomed and another inaudible 
wave which is used for repeating to Hastings 
and London." Several inquiries came to us 
regarding this inaudible wave how did it differ 
from the ordinary one? 

The use of " inaudible" in this sense is rather 
unfortunate because it expresses more and less 
than it should. It seems to say that the longer 



218 



Radio Broadcast 




MISS AGNES MILLER 

Of New York, who wrote the play "A Million Casks of 

Pronto" which won the $500 prize offered by station 

WGY, Schenectady, in its recent contest 

wave is audible whereas the short one is not. 
Now what was meant was simply this using 
an ordinary receiving set the high-frequency 
wave to Pittsburgh is of so high a frequency 
that it is generally impossible to tune-in on it. 
This is because the distributed capacity of the 
coils, tubes, and connections, is sufficiently 
great that the 94-meter wave cannot be tuned- 
in and in this sense it is inaudible. 

If about two-thirds of the turns are taken 
off the various coils used then this inaudible 
wave may become audible, provided it is recti- 
fied and amplified just as the regular wave is. 
No engineer or person in authority who uses a 
new word, or uses an old one in a new sense, 
can escape the responsibility of making his 
meaning perfectly clear. 

Distance Records During the Past Winter 

K1CORD transmissions were recorded for 
several stations during the past winter 
season, some of which are probably 
freak transmissions but long-distance records 
will become more and more common with every 
improvement in receiving and transmitting 
sets. WOR reports reaching Japan, over 
9,000 miles; WJAZ sent to Samoa, 7,000 miles; 
WLAG got through Soviet Russia to Batum, 
6,680 miles, and WGY and WEAF both have 
been heard several times in South Africa, a 
distance of 7,880 miles. The real record is 



apparently held by WHAZ of Troy which on 
four successive mornings was heard in Inver- 
cargill, New Zealand, a distance of 9,577 miles 
from Troy. 

There Are None Too Proud to Study 

THERE are few who will deny that radio 
has done more to interest the general 
public in experiment and study than 
any other development in any age. The auto- 
mobile caused many a man to wonder about 
the evaporation of gasoline when his carburetor 
did not work, and the elementary laws of the 
electric circuit came for their share of his in- 
terest when his ignition or lights failed. But 
the study excited by the automobile's mis- 
behaviour is nothing compared to that in which 
the general BCL is indulging to-day. 

In the subway we see staid business men 
devouring a serious article on radio and it is 
surely true that many a youth who previously 
spent his evenings in a corner pool room is now 
engaged in trying to beat his pal in establishing 
long-distance receiving records. A well known 
scientist expressed the idea not long ago that 
"radio is becoming vulgarized," but it seems 
that such a thought deserves but little sym- 
pathy. Possibly it would be more satisfying 
to one's vanity to feel that the branch of science 
in which he spent his investigations was far 
beyond the ken of the average human mind, 
but wouldn't it be more satisfying to know that 
his branch of knowledge was of such importance 
to the human race that everyone was striving 
to gain its portals that any contribution he 
might make would be an immediate and uni- 
versal good? 

It probably had been a source of some em- 
barrassment to the scientist we have in mind 
that some of his friends bitten by the radio bug 
had become so inoculated that their thirst for 
knowledge had prompted the questions which 
outreached his grasp of the subject. For it is 
perfectly easy to pose as an authority in a 
branch of knowledge which interests no one 
else, but it takes an able man indeed to hold a 
reputation for knowledge in such a subject as 
radio into which nearly every intelligent man 
seems to be delving so earnestly. 

A well known radio worker, when asked why 
he put wax in his sets and why he refused to 
make public the constants of the circuits said 
something to the effect that it wouldn't do 
any good anyway. He had to build twenty 



The March of Radio 



219 



sets before he could make one work, so there- 
fore it was a foregone conclusion that the 
general public would find it impossible to build 
one successfully even if the constants were 
published. 

Well, from our acquaintance with the radio 
amateurs of to-day, we wouldn't put much 
money on his opinion. Many of the "radio 
proletariat' 1 are evolving a rather fair grasp 
of the technique of radio and their knowledge is 
growing every day. The subject has ensnared 
men from all walks of life. In the colleges, 
students from every branch of engineering feel 
that they must know radio at least whatever 
else they learn. Graduates of all kinds are 
striving to master its secrets. The publishers 
of the more theoretical books on radio can 
vouch for this fact. 

We happen to know the president of a large 
electrical company who is "taking time off" to 
study radio seriously. He spends 
long hours in study and performs 
all kinds of laboratory experiments 
to expand his grasp of the subject. 
A successful bank executive is work- 
ing assiduously with a college in- 
structor for tutor, to gain such 
technique and knowledge of the 
theoretical side of radio that he " can 
help his friends "to understand their 
sets. A professor of chemistry is 
spending his evening hours, not in 
evolving more elaborate chemical 
formulae to puzzle his students (as 
perhaps he should) but in studying 
the action of loud speakers. 

Radio Antennae Are Safe 



A 



N ABANDONED antenna 
wire had been carelessly 
strung over some 2,4Oo-volt 
power wires in Montclair, N. J. and 
when some firemen were fighting a 
grass fire they came in contact with 
the dangling antenna which con- 
nected them to the high-voltage wire 
and gave two of them a fatal shock. 
This antenna was strung in a care- 
less and dangerous manner but the 
accident, while lamentable, does not 
mean that danger lurks in antennae 
and that country-wide investiga- 
tions should be started. No one but 
a fool would think of putting up a 



wire across high voltage lines even if for no 
other reason than the possibility of being 
shocked while putting it up. It is not at all 
impossible that the wire was one thrown over 
the power wires by some mischievous lad, and 
was not an antenna at all. 

More Electrodes in New Radio Tubes 

THE ubiquitous triode, with its filament 
to boil off electrons, its plate to pull 
them across the vacuum, and the grid 
to control their flow, performs such wonderful 
feats that it seems as though more than three 
electrodes in a tube would be superfluous. 
Such is not the case however; years ago a four- 
electrode tube from Schenectady, christened 
the plio-dynatron, was described and now we 
have the five-electrode tube making its appear- 
ance. This will undoubtedly perform modula- 




STATION WJAX 

Of the Union Trust Company, Cleveland, Ohio, which has just been 
moved to this location atop their new building at the corner of Euclid 
avenue and East Ninth street Cleveland's Forty-Second and Broadway 



220 



Radio Broadcast 



tion, oscillation, rectification, amplification, 
and a few other functions. Powerful an in- 
strument as the triode is, it will probably soon 
be supplanted by the quadrode or other tube 
even more liberally endowed with electrodes 
and what these multi-electrode tubes will do 
is quite beyond conception. It is probably a 
conservative statement to make that a present 
five-tube set may be equalled in the future by 
only one of the newer tubes. 

Don't Do It by Radio Unless Other 
Methods Fail 

IN OUR last number there was described a 
new radio beacon, consisting of two large 
transmitting coils placed at about 135 
degrees to each other; it had been designed for 
the Air Service, to make the navigation of 
planes easier and more reliable. 

This same type of beacon is to be installed 
at San Francisco, we learn, to guide the ferry 
boats across the bay in case of fog; it seems that 
even in the land of "sun-kissed" oranges the 
sun does sometimes hide its face so that ship- 
ping has to depend upon other than visual 
navigation. 

If we accept the claims that have been made 
for the submerged channel cable, the kind 
that was installed in New York harbor, it 




RADIO PROGRAMS ARE DISPENSED WHOLESALE 

Through this arrangement of apparatus by the telephone company at Fredonia, 

Kansas. Subscribers who purchase loud speakers for their homes through the 

telephone company are given the radio service free from this receiving station 

This service is in its second year and more than 200 loud speakers are in use 



seems that such might have solved the foggy 
harbor problem as well as or better than a radio 
beacon. Such a cable, carrying 500 cycle 
current, enabled a ship equipped with suitable 
listening coils to come into harbor through a 
narrow channel, without ever seeing a channel 
buoy. Because of the ever-increasing density 
of radio traffic the popular slogan should be. 
not "Do it by radio" but rather "Don't do 
it by radio unless other methods fail." 

Voluntary Contributions for Radio 
Programs 

STATION WHB, at the Sweeney Auto 
School in Kansas City, is apparently 
endeavoring to win our $500 prize for 
the solution of the "Who is going to pay" 
problem by direct experimental methods. Its 
listeners have been asked to send in voluntary 
contributions as their share in the upkeep cost 
of the "invisible theater." This station man- 
ager, in common with many others, has con- 
cluded that the advertising received by the 
school was not sufficient to warrant the ex- 
penditure for musicians, artists, royalties, and 
other necessary items of upkeep. 

"We believe it is only fair," says their 
announcement, "for those sharing the pleasure 
to pay a portion of the expense." We a 

with this idea heartily and 
are glad to note that at the 
latest report $3,100 had 
been contributed by the in- 
visible audience. Of course 
that amount won't go far 
towards keeping a broad- 
cast station running, but 
the audience is indeed show- 
ing an appreciative spirit. 

The Radio Corporation 
View 



IN A recent speech at 
Chicago, David Sar- 
noff, vice-president and 
general manager of the R. 
C. A., expressed his views 
on the probable and reason- 
able source of revenue for 
the support of radio broad- 
casting. After expressing 
the view that broadcasting 
would, in the future, be car- 



The March of Radio 



221 



ried out by a few superpower stations (R. C. A. 
stations we presume) he ventured the guess as 
to the proper source for the money to meet the 
ever increasing cost of maintaining a station. 

"Broadcasting, in my judgment," said he, 
"will be primarily supported by the radio in- 
dustry itself and from the returns on the sale of 
radio apparatus. A fair method of determin- 
ing the amount to be paid by each member, or 
portion of the industry, will be worked out and 
this will be based on a percentage of the sale 
price of the radio devices." 

Naturally, to the business man, this seems 
the logical solution. It is probably the simplest 
solution of the problem and possibly it will be the 
final one. A reasonable percentage on the sales 
profits in tubes, batteries, accessories, etc., will 
maintain a good many stations, even after the 
sale of new sets begin to fall off, and this 
falling off, by the way, is still a long way in the 
future. 

Holy Communion by Radio 

ALTHOUGH it must be confessed that 
nowadays we seldom enter into the 
Church's most solemn service, feeling 
that perhaps God is as much present in our 
flower garden (where Sunday morning is spent 
with the cultivator) as he is at the fiery debates 
of Modernist versus Fundamentalist, still we 
are just human enough to be unable to throw 
off the idea that the celebration of the Holy 





SECRETARY WILBUR 

Of the Navy, inspecting the central naval radio control office in 

Washington where the high power stations at Arlington, Annapolis, 

Sayville and others are controlled 



Harvey Patteson, San Antonio 

RADIO AIDED THE GOODYEAR III TO WIN 

The recent national balloon race. Pilot Ward T. Van 
Orman carried a four tube reflex set which he built him- 
self. The photograph shows the start of the race at 
San Antonio, Texas. During the winning flight of the 
Goodyear 1 1 1 to Rochester, Minnesota, where the balloon 
landed stations at Los Angeles, Cleveland, Davenport, 
Springfield (Mass.), Troy, and Schenectady were among 
those heard. The Goodyear Radio Club of Akron, Ohio, 
arranged with 16 broadcasting stations to send out ' 
regular meteorological information which proved of great 
value in navigating the balloon 



Communion is really a solemn rite, not to be 
entered into lightly and not to be used for 
Church advertising. 

Perhaps that feeling is a little old fashioned 
and squeamish. It did jolt us to hear coming 
in over WJZ's radio channel recently "Jesus 
took bread and blessed it and gave it to his 
disciples and said, Take, eat, this is my body." 
It was the communion service being 
broadcast from the West End Presby- 
terian Church of New York, the Rev. 
Dr. Edwin Keigwin officiating. We 
happened to listen-in just as the solemn 
words were being pronounced, and the 
effect was anything but religious and 
sacred. One has naturally to compose 
his thoughts to be in a mood to appre- 
ciate this, the most solemn of the 
Church's ceremonies. Whether or not 
we believe in the Transubstantiation, 
whether we are religiously inclined or 
not, we cannot help but feel that this 
service is one which should not be par- 
ticipated in by those who have not come 
to it voluntarily, such as church attend- 
ance indicates. 

Of course the minister who thus uses 
radio broadcasting may feel that he is 
accomplishing good in that a few of his 
parishioners may be bedridden, yet in 



222 



Radio Broadcast 




THE RADIO PRINTER 

Designed and developed by William H. G. Finch, radio editor of the New York American, for the International News 
Service. The system uses a radio transmitter of 200 watts power and a wavelength from 60 to 150 meters. This is the 

transmitting sending typewriter and instrument panel 



this manner be permitted in the communion 
service. This number is however comparatively 
few and the minister could just as well, or better, 
visit them in their homes, there to commune 
with them in the quietness such service de- 
mands. At the risk of being called old fash- 
ioned and out of date we venture the opinion 
that this minister did the Church a dis-service, 
by distributing his communion service, his most 
precious possession, in places where it wasn't 
welcome. 

New Edition of Circular No. 74 

EVERY technical and semi-technical 
radio enthusiast desires to have avail- 
able reliable and workable tables and 
data on radio circuits and apparatus. One of 
the very best of the books giving such informa- 
tion is published from the Bureau of Standards 
under the title of Radio Instruments, Circular 
No. 74. The first edition of the circular met 
with great favor so that the Bureau staff has 
found it worth while to revise it thoroughly 
and bring it up to date. The new edition of 
this circular is now ready and can be obtained 
for $.60 from the Superintendent of Documents, 
Government Printing Office, Washington, D. C. 



Good "Radio" Voices Are Rare 

WHEN we ventured to criticize the 
attempted French accent of one of] 
the well known announcers some; 
time ago his "boss" replied that it was not 
easy to get "a good radio voice." One would 
think that any body could talk intelligibly over 
the radio but such is not the fact. A prominent 
minister who has broadcast many sermons has 
a lamentably poor voice with which to actuate 
a microphone. The explosive voice, which 
throws quick, staccato, accents at the listeners 
is poorly adapted to the microphone. The vio- 
lent emphasis on one or two words paralyzes 
the microphone. The listener gets the effect 
of a series of grunts. A cough, which is not 
especially unpleasant when occasionally heard 
from the lecture platform, sounds like a hippo- 
potamus sneeze over the radio. A cough should 
never be permitted at a radio studio until the 
microphone has been short circuited. 

We had a treat a short time ago listening to 
a series of oddly modulated voices. The modu- 
lation was actually so poor that the event was 
extremely amusing. The menagerie of a circus 
was "put on the air" for half an hour, and the 
microphone went through all sorts of contor- 



The March of Radio 



223 



tions trying to follow the gentle accents of the 
elephants, lions, and the like. And didn't the 
sea lion enjoy broadcasting! She (it must have 
been a she) seemed to feel there were several 
listeners being charmed by her dulcet tones 
and she did her best. Even after her turn was 
over we could hear her triumphal squeals, pene- 
trating through the hyena's laugh. Few of the 
listeners had probably heard the hyena laugh be- 
fore since he is generally a quiet kind of a beast. 

Following this interesting bit of Nature 
broadcasting we hear that 2LO intends to 
sneak a microphone out into the dells where the 
nightingale holds forth and thus give to this far- 
famed songster an audience of the size he really 
deserves. And Paris, not to be outdone, is 
going to put on similar Nature programs. 

If this type of broadcasting increases in 
popularity it will be necessary to adopt some 
new scheme of modulation or else to train the 
elephants and lions to be more gentle. 

How Radio Saved U. S. Troops from the 
U Boats 

AT A recent meeting of the Federal Club 
at the Bureau of Standards, one of the 
speakers, Commander D. C. Bingham, 
of the Naval Communications Division, gave 



a short but illuminating talk on the part 
radio played in the successful transportation 
of American troops through the submarine- 
infested waters around the British and French 
coasts. The radio direction finder, according 
to Commander Bingham, was largely respon- 
sible for the ineffectiveness of the German U 
boats in preventing the movement of our troops 
to France. The submarines had radio, and of 
course, they used it, perhaps not more than 
they had to, but still enough to give themselves 
away. Allied shore stations, equipped with di- 
rection finders, could locate them and follow 
them through their journeys. The approximate 
location of the boats being known, the troop 
ships on their way across were routed in such a 
way that they missed the waiting submarines. 

In case a submarine kept quiet for a day or 
two, ever-widening circles were drawn around 
the point where she was last heard from, thus 
indicating the territory in which she must be, 
because of her known cruising speed and the 
time elapsed. The troop ships were, in so far 
as possible, kept outside these circles. 

We well remember one troop ship thus being 
kept outside an imaginary circle and the circle 
got so big that it seemed we nearly hit Iceland 
before instructions were received by radio to 
turn towards port. 




THE RECEIVING RADIO TYPEWRITER 

And its inventor, W. H. G. Finch (right). An accuracy of 99! per cent, at 65 words a minute was attained 
at its first public trial at the Waldorf Hotel, New York, during a recent convention of newspaper publishers 



Come With Me 'Neath the Family 

Tree 

Read the Story of the Radio Detector's Best Booster, the Ever-present Help in 
Time of Trouble Radio- frequency Amplification. Applying Family Tree Me- 
thods to the Hundred-and-one Trade Names for this Form of Amplification 

BY JULIAN KAY 



This is the second of a series of avowedly breezy explanatory articles designed to put the 
non-technical reader at his ease when staggering radio terms and phrases and circuits are 
conversationally hurled at him. The reader will find in the "Family Tree" an orderly and 
unusual grouping of radio names and circuits which he will do well to preserve. The first 
article which classified radio receivers and circuits appeared in June. THE EDITOR. 



EVERYONE who has a radio has a 
detector in some one of its many 
forms. This is the essential part 
of any receiving equipment about 
which all the other apparatus is 
grouped. In the first article of this series, 
something was said of the function of a de- 
tector likening it to our ears as the organ that 
"hears" the radio sig- 
nals. 

Now, given a detec- 
tor, what can we do 
to increase its value? 
The thing that nat- 
urally comes to mind 
is to use amplifiers, 
and since everyone 
is talking "radio- 
frequency" amplifica- 
tion, we shall apply 
our previous Family 
Tree methods to it. 
So much is claimed 
for this method of 
amplification that one 
almost considers it as 
a general palliative 
for all modern radio 
ills. If your radio is 
weak and pale, un- 
able to go great distances, liable to get ner- 
vous and confused if two stations are trans- 
mitting at the same time, if, in short, it is 
in a state of general debility, what can be 
done? 



Do You Know 

The difference between radio- and audio- 
j requeue)' amplification? 

When radio amplification is better for a given 
result than audio? 

Wbat part transformers, variometers, and 
resistances play in a radio-frequency circuit? 
Wloy transformers are better for inter-stage 
coupling than other coupling devices? 
How radio-frequency amplification compares 
with regeneration for sensitivitv? 
What impedance-coupling means? 
frby "heterodyning" is advantageous? 
What "tube capacity" is and what difficulty ii 
causes in receivers, and how this difficult 'v is 
commonly obviated? 

What a "losser" is and what receivers use 
them? 

Wbat the 57^ angle is? 
Wbat to do for a "pale and weak radio"? 



The answer is radio-frequency, for it will do 
the following things to your present set: 

1. Add selectivity. 

2. Increase the receiving range. 

3. Add volume to the final signals. 

4. Help to overcome static. 

For instance, with one stage of radio- 
frequency amplifica- 
tion before a regenera- 
tive detector and two 
steps of low-frequency 
a m p 1 i f i c a tion four 
UV-IQ9 tubes in all 
it is possible to hear 
Chicago stations in a 
New York city apart- 
ment when five local 
stations are transmit- 
ting. 

Without the radio- 
frequency stage, local 
stations can be sepa- 
rated only when the 
detector tube is oscil- 
lating and making the 
neighbors swear, and 
distant stations are 
not heard clearly un- 
til after midnight. 
For the city dweller, this type of amplifica- 
tion to help the detector do its tricks is a great 
boon; for the fortunate country home it makes 
many of the magazine advertisements come 
true. 



'Neath the Family Tree 



225 



The methods of adding a stage of radio- 
frequency amplification have been previously 
described in RADIO BROADCAST, and those who 
have made it work already know its value. 
If it does not work to suit the builder, one of 
two things must be wrong, either it is not prop- 
erly constructed and operated, or perhaps the 
builder expected too much. 

If one should suddenly see Niagara Falls 
without having heard of this natural wonder, 
he should be amazed and awed at its grandeur, 
but having been brought up from childhood 
in the belief that it is unsurpassed, we are only 
awed and amazed when seeing it for the first 
time that we believed all the wonderful things 
said about it. The statistics are interesting 
the fall is 168 feet high and not a mile, and 
one million several hundred thousand newly- 
weds gaze at it each spring but 

The trouble is that we expect too much. 

HOW R. F. AMPLIFICATION WORKS 

F^v ETECTORS are peculiar devices. They 

1 / do not follow the "straight and narrow" 

but go off on a tangent and act according to 
what is known as a "square law." Their 
function is to distort the inaudible energy 
coming down the antenna in such a fashion 
that the ear, with the aid of accessory appara- 
tus, hears audible sounds. 

The square law comes in the picture in the 
following manner. If twice the voltage is 
applied to the detector in one case as in an- 
other, the detector output will be multiplied 
by four instead of two. Here is where radio- 
frequency amplification, which takes place be- 
fore the detector, gets in its good licks. 

If an amplifier boosts the incoming energy 
three times and then delivers it to the grid of a 
detector, the latter in turn will deliver nine 




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times as much voltage as it would without the 
previous amplification. 

Of course we shall not hear nine times as 
much sound, for the ears have some idiosyn- 
crasies of their own but you can see what 
radio-frequency amplification does to a weak 
and debilitated detector. 

There is another advantage in amplifying 
before detecting. The currents after the de- 
tector tube are all of low frequency, since it is 
these that we actually hear. For this reason 
any noises in the circuit itself say, bad B 
batteries, loose connections, microphonic 
"bongs" all will be audible and increased in 
strength by the low-frequency amplifiers, but 
are not so likely to cause trouble in a high- 
(radio) frequency amplifier. Still another ad- 
vantage lies in the difficulty of making dis- 
tortionless audio amplifiers. 

THE R. F. FAMILY TREE 

THE principle of radio-frequency ampli- 
fication is simple. The input or grid is 
tuned to the incoming signal which is amplified 
by the tube and then passed on to the next 
amplifier or detector. The many types and 
names arise from the many methods of coupl- 
ing the various stages together, and the me- 
thods of keeping the amplifiers from oscillating. 
The Family Tree shows the two general 
methods of coupling: resistance and induc- 
tance. The first is not used for radio fre- 
quencies because of the short circuiting effect 
of the tube capacity (grid to plate). Induc- 
tance-coupling can be of two types, either a 
single coil known as impedance-coupling, or a 
two-winding transformer. Naturally, either 
of these methods can be tuned to the wave- 
length desired with added selectivity and 
amplification. If the coils are merely used to 
couple the tubes together, say by using an 
Acme or Duratran or any of the transformers 
mentioned on the Family Tree, one tuning 
control is eliminated. 













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'Neath the Family Tree 



227 



A single stage of untuned radio-frequency 
amplification is not as good as a single regen- 
erative detector, but by tuning this one 
stage, remarkable results can be had. The 
transformer has two advantages over the single 
coil such as a variometer, that of greater 



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tuning range and the fact that such amplifiers 
are easier to reflex. The greater amplification 
resulting from pure inductance tuning vario- 
meter may be offset by using a "step-up" 
in the transformer. On the other hand the 
losses are greater in two windings of a trans- 
former than in the one winding of a single coil. 

It should be noted that when a single winding 
or a variometer is used, a condenser must be 
inserted before the grid of the next tube to 
keep the B battery voltage from that grid. 

The Teledyne receiver described in RADIO 
BROADCAST for May uses one stage of tuned 
transformer-coupled radio-frequency amplifi- 
cation. Other receivers now on the market 
using this general method of attaining dis- 
tance and selectivity are the Atwater Kent five- 
and six-tube receivers. All Neutrodynes, 
some Superdynes, and the Grebe CR-I2 use 
this method and are explained in detail in 
following paragraphs. 

Reflex methods usually use untuned trans- 
formers, but the loss by such methods is made 
up by passing the energy through each am 
plifier two or more times. These receivers 
are simple to operate, for there are at most two 
tuning controls, and with efficient radio- and 
audio-frequency transformers they should give 
good results over the entire broadcast range. 
The Acme Triflex, the Grimes Inverse Duplex, 
the Sleeper Monotrol, and the DeForest Re- 
flex, are good examples of commercial re- 
ceivers employing this method of amplification. 

RADIO-FREQUENCY DIFFICULTIES 

LIKE most good things on this earth, 
radio-frequency amplification is fine 
except for one small difficulty. This trouble 



arises from an inherent defect in our present 
vacuum tubes, the fact that there is a small 
electrostatic capacity existing between the grid 
and plate. This provides a path for the alter- 
nating plate current to get back to the grid 
circuit where it is again amplified and passed 
to the plate. This process keeps up until the 
circuit oscillates. The result is that a large 
oscillating current passes around from grid to 
plate and back again so that the minute an- 
tenna currents are lost in the shuffle. All we 
hear is a shriek and groan and neighbors prob- 
ably say, 

" By golly, there's that single circuit hound 
again." 

At the present time there are three methods 
of attacking this problem of feed-back cur- 
rents: 

1. "Losser" methods. 

2. Reversed feed-back (Superdyne). 

3. Balancing methods. (Neutrodyne). 

The first of these three is an old scheme and 
is usually disguised under the general term of 
"stabilizers." It is used on receivers built 
by manufacturers who are not licensed to use 
the more modern and efficient methods dis- 
closed by Rice and Hazeltine. 

Fig. 4 shows the "losser" methods. Here 
enough resistance is added to the circuit, either 
in series or shunt to cut down the amplification 
to a point where oscillations do not occur. 
The other method is that of placing a poten- 
tiometer across the A battery with the variable 
arm connected to the grid return end of the 
input tuning coil. When the circuit starts 
to oscillate the operator shifts this variable 



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arm until the grid becomes slightly positive 
thereby stopping the oscillatory currents. 

Both of these methods involve adding losses 
to the amplifier, in other words, decreasing 
the amplification. This of course is inefficient 
although simple to operate. 



228 



Radio Broadcast 



F1GU& 5 




M/l6NETiC FEEDBACK. 



The second method, the reversed tickler, is 
used in the Superdyne and does not introduce 
losses into the circuit except for what voltage 
is lost in the tickler coil. The scheme re- 
sembles the "tickler" feed-back detector ex- 
cept that the tickler coil is reversed in direction 
so that instead of forcing the circuit to oscillate, 
it prevents oscillation. If the circuit should 
break into oscillation no signals can be received 
and the operator will at once be aware that his 
amplifier is in trouble. 

Both of these two methods have the dis- 
advantage that they require adjustment one 
more dial to turn. In the Superdyne receiver 
this is not such a bother, since the circuit can 
be adjusted for each wavelength and brought 
as near actual oscillation as is desired. 

THE NEUTRODYNE RECEIVERS 

THE balancing methods, of which the 
Neutrodyne is the typical example, are per- 
haps the best for eliminating the bad effects 
caused by grid-to-plate tube capacity. The 
advantages of the Rice and Hazeltine circuits 
over other schemes are apparent when one 
considers the following: 

1. Once adjusted for a particular tube, the bal- 
ancing need not be changed. 

2. There are no added controls, no more dials to 
juggle. 

3. No losses are introduced, that is, the full gain 
of the amplifier may be utilized. 

4. Many stages of amplification can be worked 
if each is properly neutralized. 

5. The balancing is practically independent of 
wavelength. 

The Neutrodyne principle is one of balanc- 
ing the small feed back current by another 
capacity current of an exactly equal strength 
but fed into the circuit in opposite direction 
the result being that no current actually flows. 
This method isolates the grid and plate cir- 



cuits so that they may be sharply tuned to the 
same wavelength without sensible interaction. 
The grid of the tube can be kept negative by 
C batteries, and large values of B battery volt- 
age used thereby getting the maximum benefit 
from the amplifier tubes. 

The Hazeltine method is shown in outline 
Fig. 6. The neutralizing condenser, com- 
monly called a "neutrodon" is connected to 
the following tube in such a manner that the 
proper magnitude and phase of the balancing 
current is maintained. The actual method of 
adjusting these small capacities has been 
described in RADIO BROADCAST. It is quite 
important that the exact point of balance be 
found, for over-neutralizing is just as bad as 
no neutralizing at all. 

The Rice circuit has a slight advantage over 
the usual scheme in that the balancing capacity 
is kept in the circuit of the tube being neu- 
tralized. Thus any type of output can be used. 
Care must be taken here that the neutralizing 
condenser does not short or the B battery 
will be on the amplifier filaments. 

The usual "five-tube receiver" is a Neutro- 
dyne in which two tubes act as radio-frequency 
amplifiers, one as a detector, and two as audio- 
frequency amplifiers. It is possible to use 
small tubes, say UV-igg, for the first three, 
but larger capacity tubes such as the UV-2OI 
A should be used in the last stages to handle 
the output without overloading. The two 
radio tubes can be reflexed, that is the audio- 
frequency currents delivered by the detector 
can be sent back through the first two tubes, 
but in general there is little to be gained in such 
a method. The four-tube sets are of one of 
two types; either they have but one stage of 
radio amplification, or but one of the radio 
tubes is reflexed. The Fada " 160" and the 
Garod are examples of the latter. 

Some confusion seems to exist about the 
need for neutralization or for stabilizers. The 
rule of whether to use some one of these oscil- 

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'Neath the Family Tree 



229 



lation preventing methods or not is simple; if 
the radio-frequency circuit oscillates at the 
lower wavelengths, neutralize or stabilize it. 
If the circuit does not oscillate, there is no 
necessity of complicating it. Sometimes the 
disposition of coils and leads is such that neu- 
tralization is automatically affected without 
further trouble but, if the tube does not 
oscillate, it is usually a sign that it is not 
in an efficient circuit. 

For example, let us take the Hazeltine (Neu- 
trodyne) circuit. If the primary winding of 
the radio-frequency transformers has but few 
turns, it is probable that the circuit will not 
oscillate, but the full gain of the tube will not 
be realized. The remedy is to increase the 
number of primary turns until oscillations ac- 
tually occur on the longer wavelengths, 
then neutralize the tube. Those who use the 
Rice circuit can do the same thing by removing 
the filament tap from the center of the coil and 
bringing it nearer the bottom or plate end of 
the coil. This increases the voltage across the 
input, and a point will be reached where the 
circuit actually oscillates. There is no need 
to neutralize before this point is reached. 

In all neutralizing schemes, it is important 
to have no electromagnetic coupling between 
the various coils. This can be accomplished 
by placing the coils at right angles to each 



FIGURE / 



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O ' 


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DETECTOR 


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o 

O 

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other and far apart, or by assuming the well 
known "57^" degree angle of the coils. 

A well-made receiver employing two stages 
of radio-frequency amplification or one stage 
plus detector regeneration should be able to. 
cover the entire United States broadcasting 
area. Where one wants strong signals and 
great distances, the 201 -A tubes are unexcelled; 
for less powerful signals the 199'$ are extremely 
economical and efficient. 

Radio has been referred to as the magic 
carpet on which we may ride to the ends of the 
land. This is theoretically possible radio- 
frequency amplification makes a pleasant the- 
ory into practicality. 

In the next article, the super-heterodyne, 
another and very well-known radio-frequency 
receiver, will be described. 



O0A/E of the prize-winning receivers and stations in our "How 
^ Far Have You Heard" distance contest will be described in the 
August number of RADIO BROADCAST. 



How to Charge Your Storage B Battery 
from an A Battery Rectifier 

A Few Feet of Lamp Cord, a Socket, a Hundred-Watt Lamp, and an Ammeter are the 
Simple Essentials Required to Convert any A Battery Rectifier into a B Battery Charger 



BY ZEH BOUCK 



In this article, Mr. Bouck tells how the various types of A battery chargers now on the 
market can be made to charge storage B batteries without expensive auxiliary equipment. 
He also touches on the theoretical operation of the rectifiers he describes so the reader may 
more perfectly comprehend the principles with which he is experimenting. Many enthusiasts 
are no longer satisfied merely to "read" radio. Instead, they study it. It is only by under- 
standing both the theoretical and practical aspects of an electrical problem that the experi- 
menter can obtain the highest efficiency from his apparatus. THE EDITOR 



RECTIFICATION, as most of us 
know, means the changing of 
an alternating current, which in 
commercial frequencies reverses its 
direction of flow from twenty-five 
to sixty times a second, to a direct current 
that, though it may be pulsating, maintains 
its periodic push in one direction. Rectifica- 
tion is most simply accomplished by smothering 
or cutting off one half of the A. C. alterna- 
tion so that (say sixty times a second) we shall 
get very decided unidirectional electrical im- 
pulses. 

Several electrical processes, such as the 




FIG. I 
A typical lead-plate acid storage B battery 

charging of storage batteries, require direct 
current, and where A. C. is the only convenient 
power source, rectification is the most simple 
and logical method of supplying this one- 



direction current. Due to certain advantages 
in alternating current distribution, a majority 
of homes are electrified with A. C. in preference 
to D. C. Most of our readers are therefore 
familiar with the principle of rectification 




FIG. 2 

Charging a B battery from direct current light- 
ing mains. Note the series-parallel connection 



through the common use of rectifiers for charg- 
ing storage A batteries, which, until the advent 
of the dry-cell tube, was the only practical way 
of lighting the tube filament. 

The popularity of the multi-tube receiver, 
and more particularly special cases as the super- 
heterodyne and resistance-coupled amplifiers, 
has bespoken the very pronounced advantages 
of the storage B battery, and again presents 
the problem of rectification which the dry-cell 
A battery had perhaps tended to eliminate. 



How to Charge Your Storage B Battery from an A Battery Rectifier 231 




FIG. 3 

The two meters in the upper right illustrate the inaccuracy of the 
standard D. C. meter on a pulsating current. The upper meter is 

correct 



Storage B batteries are obtainable in two 
electrical types, generally recognizable by 
certain consistent mechanical characteristics 
the lead-plate-acid cells and the Edison nickel- 
iron battery. The lead plate cell, a battery 
of which is shown in Fig. i, is a minature A 
battery in both appearance and construction. 
These batteries are generally manufactured in 
24-volt blocks, two or more sections being con- 
nected in series for high amplifying potentials, 
and in parallel for charging. 

The Edison cells are usually built up in a 
test-tube rack, such as the battery shown 
undergoing charge in Fig. 7. Sizes of these are 
obtainable in tapped voltages up to one 
hundred and forty volts. Switches are pro- 
vided which break up the battery into smaller 
units and connect them in parallel for charge. 



The characteristics of each type 
of battery will have a different 
appeal to individual experimenters, 
and to an extent will affect their 
adaptability to taking a charge from 
various A battery rectifiers. The 
lead battery probably holds its 
charge longer or more consistently, 
will give greater current, and suffers 
less from voltage drop during a nor- 
mal discharge. The Edison cell, on 
the other hand, is cheaper when high 
voltages are desired, and, as it is ap- 
parently immune from abuse, has a 
longer life. It goes without saying 
that the maintenance of these bat- 
teries differs with their differing 
electrical characteristics, and the 
instructions of the individual man- 
ufacturers should be studied and 
observed in every case, occasionally 
modifying the charging instructions 
with the suggestions given in this 
article. 

CHARGING THE BATTERY 

IF THE reader is one of the for- 
tunate minority whose home is 
lighted by direct current, (D. C.), 
he may of course charge his battery 
without the aid of a rectifier. Fig. 2 
shows how this may be done, and 
also illustrates the principle of series- 
parallel connection. Six 24-volt 
batteries giving a series potential of 
i44-volts, have been broken up into 




FIG. 4 

Converting the Tungar type A battery charger 



232 



Radio Broadcast 



48-volt units and connected in parallel. L is 
a 73- or loo-watt lamp which passes a charging 
current of about .4 ampere. The meter is not 
necessary but it is very desirable as both a 
polarity indicator and an indication of the 
charging rate. 

In charging from alternating current, a 
rectifier is needed in addition to a loo-watt 
lamp and the meter. The meter should read 
from zero to one ampere, but in the case of 
a rectified current it is an indication of polarity 
rather than a reliable reading of the charging 
current. As before mentioned, the rectified 
current is pulsating, rising from zero to maxi- 
mum and falling to zero again. Due to the 
reactance in the winding of the direct current 
meter, .a quality which, as we have had oc- 
casion to explain before, opposes any current 
change, only a small amount of the available 
current is permitted to actuate the meter. 
The meter indicates only about two thirds of 
the total direct current passing through the 
circuit. Fig. 3, showing a hot-wire meter 
connected in series with a magnetic meter, 
illustrates this discrepancy, the former meter 
registering the true current. The D. C. in- 
strument is emphatically unreliable in the case 
of chemical rectifiers, where the alternating 
current inadvertently passed through the cells 
has no effect whatever on the needle but will 
register a very definite deflection on the hot- 
wire meter. The D. C. meter, however, is 
preferable in all cases, for the one third allow- 
ance is easily made, and the needle is a reliable 
indication of the direction of current, which is 
most important. 





FIG. 5 
Doing the same with the separate winding transformer 



i :G. 

A typical bulb rectifier designed for charging storage 

A batteries. This article tells how to charge B batteries 

with it 



THE RECTIFIER 

THE rectifiers we shall discuss in this article 
are those originally designed for charging 
storage A batteries. These arrange them- 
selves into three classes, designating the princi- 
ples upon which they function. The first, and 
probably the most popular, is the bulb rectifier, 
such as the Tungar, Rectigon, and King. The 
next most common is the mechanical, or vi- 
brating rectifier, good examples of which are 
found in the Leich, Valley, Apco, Handy 
Charger, Unitron, Homcharger and La France. 
Last in place, but by no means so in merit, 
is the efficient chemical rectifier such as the 
Fansteel Balkite. 

The manufacturers of one or two of these 
chargers, anticipating the demand that is 
following the widespread appreciation of the 
storage B battery, have designed attachments 
which adapt their chargers to higher voltage 
batteries. These attachments, however, are 
generally superficial additions of which the 
experimenter can easily avail himself without 
further expense. A few feet of lamp cord, a 
socket, a loo-watt lamp and the meter are 
all that is necessary to convert any A battery 
rectifier into a B battery charger. 

CONVERTING THE BULB RECTIFIER 

MOST enthusiasts who are at all familiar 
with the action of the three-element 
vacuum tube comprehend the principle upon 
which the two-element valve, such as the 
Tungar, functions. When the positive half of 



How to Charge Your Storage B Battery from an A Battery Rectifier 233 



the cycle is applied to the plate of the tube, 
electrons are drawn over from the filament, and 
current passes through the bulb and the bat- 
tery, which is included in the plate circuit. On 
the negative half of the cycle the plate charge is 
reversed, the "like charge" repels the electrons 
thrown off by the filament, and no current 
passes. 

There are two types of bulb rectifiers in use 
for battery charging, one employing the auto- 
transformer (Fig. 4A) and the other using the 
conventional transformer with separate prim- 
ary and secondary windings (Fig. 5A). In 
the auto-transformer diagrammed in Fig. 4A, 
the entire winding functions as the i lo-volt 
primary. The turns braced by i act as the 
filament lighting secondary, while the sec- 
tion braced at 2 furnishes the higher po- 
tential for charging the battery. The Tungar 
rectifier is of this type, and is quite easily 
converted into a B battery charger. 

As is shown in the diagram, one side of the 
A. C. line connects to the filament. It is 
first necessary to determine which side of the 
line this is. Disconnect the connection to the 
plate of the rectifying tube by slipping off the 
Fahnestock clip, and plug the rectifier into a 
lamp socket. Now take an electric light bulb 
and connect one side of it to the filament of the 
rectifier. The free end of the connections lead- 
ing to this bulb is touched first to one side of 
the alternating current line and then to the 
other. The side on which the i lo-volt lamp 
lights to its full brilliancy is quite evidently 
the side not connected to the filament. A tag 
or other means of identification should be 
affixed to it to designate this wire as "X" 
of Fig. 46. The remaining connections are 





FIG. 7 

Charging a forty-volt B battery (three sections in parallel) from a con- 
verted A battery charger. On discharge this battery gives more than 

120 volts 



FIG. 8 
An A battery charger of the vibrating type 

followed accordingly. " X" runs to the lamp; 
from the lamp to the meter; from the meter to 
the plus of the storage B battery, and from the 
minus of the battery to the plate of the tube. 

A charger of the separate-winding type is 
illustrated in photograph Fig. 6. If the experi- 
menter is in doubt as to the connections of his 
charger, the test suggested in the preceding 
paragraph for locating side "X", will deter- 
mine the type of transformer used. If the test 
lamp does not light on either adjustment, it is 
evident that there is no connection between the 
primary of the charger and the filament light- 
ing secondary, i, e., the circuit of the charger is 
that shown in Fig. 5 A. In con- 
verting a charger of this type, one 
side of the no-volts is connected 
deliberately to the rectifier fila- 
ment, while the remaining side, 
"X" again, is connected to the 
lamp and meter in the same way 
as with the Tungar machine. Fig. 
56 shows the separate-winding rec- 
tifier arranged for charging storage 
B batteries. 

L, in both Figs. 4 and 5, is the 
loo-watt lamp, and M is the direct 
current meter already described. If 
more convenient, an electric solder- 
ing iron may be substituted for the 
lamp. Fig. 6 shows the A battery 



234 



Radio Broadcast 




4 



TO 
A "B" 8ATT. 



FIG. 9 

How to connect the vibrating charger for charging a 
forty-volt B battery. The vibrating mechanism is con- 
nected to the 1 10 volt line as usual 



charger made by the King Electric Company 
charging an Edison storage B battery. 

THE VIBRATING OR MECHANICAL RECTIFIER 

THE mechanical rectifier is nothing more 
than an automatic switch for connecting 
the battery to the charging potential when the 
current is in one direction, and breaking 
the circuit on the other half of the cycle. This 
is most simply accomplished magnetically, 
through a combination of permanent- and 
electro-magnets, the winding of the latter 
being placed over the former as a core. When 
an alternating current is passed through the 
coils, the core is given a magnetizing impulse 
first in one direction and then in the other (the 
polarity of an electro-magnet is of course 
determined by the direction of the current 
responsible for its magnetism.) Thus on one 
half of a cycle, the magnetic attraction of the 
permanent magnet for a near-by armature will 
be augmented by the electro-magnetic effect 
while on the other half, due to the opposing 
magnetic fields, there will exist little or no 
attraction. The armature will therefore be 
pulled to the magnet sixty times a second, and, 
if suitable contacts are provided, mechanical 
rectification becomes an obvious and simple 
matter. Other types of magnetic rectifiers 
utilize a polarized armature, but the principle 
of opposing and cooperative magnetic fields 
remains the same. Fig. 7 is a photograph of 
one of the most efficient rectifiers of this type, 
and upon which the experiments described in 
the following paragraph were made. 

In converting magnetic A battery rectifiers 
for charging higher voltages, the various recti- 
fying circuits and they are several need not 
be considered individually. The actual ori- 
ginal circuit may be partially ignored, and the 
reader's attention concentrated on running 
two free leads, one to the vibrating arm (X 
in Fig. 8) and the other to a stationary con- 
tact (Y). On most rectifiers, two contacts 



will be found placed on opposite sides of the 
vibrating armature. It occasionally happens 
that only one stationary contact is connected to 
the A battery charging circuit, which makes the 
free contact particularly adaptable to our pur- 
pose. However, either contact may be used. 

It is next necessary to determine if the 
armature and both stationary contacts are 
isolated from the 1 10- volts. A test lamp is 
best employed, after the manner described 
for tracing the bulb rectifier circuits. One 
terminal is connected first to the contacts, 
one at a time, and then to the armature, the 
remaining terminal being touched to each 
side of the i m-volts. The test is, of course, 
made when the rectifier is plugged into 
the lighting circuit. Negative results indicate 
the desired isolation. As separate winding 
transformers are used in the majority of mag- 
netic rectifiers, this will probably be the case. 
If, however, the tests show a circuit complexity, 
it will be necessary to break the undesired 
connections, leaving the stationary contact 
points free from direct connection with the 
i lo-volt line. 

Thearmatureandcontact point are then wired 
as shown in Fig. 8. L and A are the lamp and 
meter already described. It is a fifty-fifty 
chance that it will be necessary to reverse the 
leads at BC as suggested by the dotted lines. 
Fig. 9 shows the ensemble in action. 

THE CHEMICAL RECTIFIER 

THE chemical rectifier is one of the oldest 
known means of converting alternating 
current into direct current. The improve- 
ments which have made it a very efficient 
and convenient system to-day, have not altered 
the principle of its functioning. On half of 
the alternating current cycle, one of the two 
electrodes is enveloped in bubbles, forming a 
gaseous and insulating film which breaks the 
circuit until they are dissipated by the reversal 
of the alternating current. 

The Fansteel Balkite is the best and perhaps 
the only representative of this type of rectifier 
available to the broadcast enthusiast for the 
charging of storage A batteries. This rectifier 
may also be used for charging a 24-volt 
unit of storage B battery without any altera- 
tions whatever, half of a 24-volt battery 
merely being clipped into the circuit in place 
of the usual six-volt accumulator. The higher 
potential of the B battery reduces the poten- 
tial difference between the output of the 



How to Charge Your Storage B Battery from an A Battery Rectifier 235 



rectifier and the battery undergoing charge, 
with a corresponding reduction in the charging 
rate which drops to about .3 ampere. The 
manufacturers' of this rectifier will send to in- 
terested readers corroborative data on this 
particular method of charging. 

A 24-volt battery may also be charged as a 
single unit, by leading the i lo-volts directly to 
the rectifying cell, and from there to the battery 
as shown in Fig. 10. Again it may be necessary 
to reverse the leads at BC. Fig. 1 1 shows this 
arrangement charging 24-volts of B battery, and 
the reader may observe the connections soldered 
to the rectifying cell terminals. The Balkite 
rectifier, fed from no-volts, A. C, does not 
charge satisfactorily when the normal battery 
voltage is over thirty. In using the Fansteel 
charger for B batteries, it is suggested that they 
be connected in parallel units not exceeding 
this voltage. 

While this system of rectification works well 



on all batteries, it is more satisfactory on the 
lead plate cells, due to the efficiency with which 
such batteries accumulate a charge at very low 
rates. The Edison cell takes a charge best at 
a comparatively high amperage. For this 
reason, when charging the latter type, parti- 
cular care must be observed to maintain the 
electrolyte at the proper height in the Balkite 
cell, or, more technically, at the proper specific 
gravity. It is at this strength that the solution 
offers the least resistance to the current, and 
therefore passes the highest amperage. Need- 
less to say, the efficient operator will maintain 
the desired specific gravity at all times, regard- 
less of the type of battery being charged. Very 
few of us are efficient operators. 

CONCLUSION 

PXCEPT where the voltage is specifically 
L_j stated in the foregoing paragraphs, it 
has been assumed that the battery will be 




FIG. 10 

Charging the B battery with the vibrating rectifier. An electric soldering iron 
may be plugged in, adding the needed resistance in place of the electric light bulb 



230 



Radio Broadcast 



\ c / w 

K 

J /'B\ 


TO 

'&" BATT. 


*i r 




> ; : 

g 
! 


RECTIFIER 
CELL 


J 



FIG. I I 

How to connect the no volts directly to the Balkite 

rectifying cell for charging a B battery as a twenty-two- 

volt unit 



charged as a 48-volt unit. It is difficult to 
charge a higher voltage than this without re- 
course to a step-up transformer. The experi- 



menter, however, may charge his cells as a 
24-volt battery. This is particularly conveni- 
ent in the case of a 72-volt battery built up 
of three 24-volt blocks. No ' change in the 
charging apparatus is necessary to compensate 
for the current, which automatically adjusts 
itself by flowing through more parallel units. 

The B battery should be disconnected from 
the receiver while undergoing charge, and the 
possibility of a grounded connection should be 
assiduously avoided. Do not attempt to 
charge A and B batteries simultaneously from 
the same rectifier, unless you are sure, very sure, 
of your circuit. It can of course be done, the 
author does it, but he has discovered that in 
doing so it is a good idea to supplement one's 
genius with a supply of fuses. 




FIG. 12 



The Balkite B battery arrangement in action. The transformer 
of the rectifier has been substituted for the usual electric light bulb 



JLJOl an amateur can make a receiver for very short waves will be the subject of the 
next of Mr. Bouck's how-to-build-it articles, appearing in August. A very sensi- 
tive and economical non-radiating circuit never before used for the reception of wo-meter 
waves is employed. 



Man-Made Static 



Showing That Some "Static" is Native to Poorly 
Built Receivers How to Test a Suspected Set 

By A. F. VAN DYCK 

Engineer, Technical Division, Radio Corporation of America 

PART III 



T 



WO previous articles have described 
various causes of interference with 
radio reception originating in electric 
power circuits or devices, and meth- 
ods of eliminating those disturbances. 
There are some general aspects of the subject, 
not covered in these previous articles, which 
should receive consideration by every broadcast 
listener who believes 
that interference 
which he experiences 
is due to such causes. 
Then the broadcast 
listener can find a 
solution for his parti- 
cular problem, with 
minimum trouble to 
himself and to others. 
As the number of 
broadcast receivers in- 
creases, the number of 
cases of interference 
reported grows also. 
The number of cases 
reported to radio and 
power companies has 
attained large proportions. This has given 
such agencies good opportunity to study such 
interference. 

The most interesting and important discovery 
brought to light by these companies is that a 
large percentage of complaints of interference 
are not due to outside interference at all, but 
are caused by defects in the complainant's re- 
ceiver. This has been found especially true of 
home-made receivers built by persons with 
little or no electrical experience. Bad con- 
tacts, poor soldering (or no soldering at all) 
broken wires, run-down B batteries, are sources 
of noises which are none too easy for the novice 
to find, so that he very often concludes that the 
noises he hears are due to "interference." He 



All That Scratches 

Isn't static, as Mr. Van Dyck points out. 
Inexperienced enthusiasts can build a receiver 
fairly bristling with potential scratchings and 
bowlings by being satisfied with little or no 
soldering, "poor contacts and careless work- 
manship in general. 

Power companies aren't altogether to blame 
for the unearthly noises your set may vent 
but when they are to blame, they are mighty 
willing to "shoot trouble." Here is some good 
advice to look carefully before you take a 
petulant radio leap and blame your "inter- 
ference" on all and sundry. THE EDITOR 



may blame the amateur, the commercial sta- 
tion, the power company, or any one else on 
whom his imagination may alight. 

HOW TO TEST FOR A FAULTY RECEIVER 

THE first thing to do when noises are heard 
in a receiver is to make sure that they are 
not originating in the receiver itself. A first and 

informative test is to 
connect together the 
antenna and ground 
terminals of the re- 
ceiver with a piece of 
wire. This prevents 
any voltages in the an- 
tenna from actuating 
the receiver, and if the 
noises are still heard 
it is absolutely certain 
that they are being 
caused within the re- 
ceiver, and are not 
coming by way of the 
antenna. When such 
a connection is made 
on a receiver which 
is in good condition, perfect silence in the 
loud speaker (or headset) will be had. 

The next general observation of importance 
made in study of large numbers of complaints 
to power companies, is that much trouble is 
caused by standard devices connected to power 
lines by individual owners, and therefore, over 
which the power companies have no control. 
Devices such as heating pads, violet-ray 
machines, elevator motors, etc., may cause in- 
terference but through no fault of the power 
company whose responsibility is merely to 
supply power to the user. It is important to 
appreciate this, because it is useless to ask a 
power company to eliminate a source of inter- 
ference over which it has no control. 



238 



Radio Broadcast 



GET THE FACTS BEFORE YOU COMPLAIN 

THE second thing for a broadcast listener 
to do when he experiences interference of 
this sort, provided the first test has proved that 
the trouble is not in his receiver, is to determine 
the nature and general source of the distur- 
bance, or if he can't carry out this work person- 
ally to engage the services of a radio expert to 
do so. The object of this second test is to 
determine whether the trouble is caused by any 
electrical device or circuit in the same house 
with the receiver, whether it comes into the 
house over the power lines which furnish power 
to the house (these questions can be studied by 
switching off all devices in the house and finally 
by opening the main switch, usually located 
near the meter, or removing the fuses if the 
interference is actually coming in on the house 
power wires it will be affected by opening the 
switch, although not necessarily stopped) and 
whether the other receivers in the neighborhood 
experience the same interference. Intelligent 
execution of this second step is essential before 
anything else can be done and before any com- 
plaints can justly be made to any one. If the 
source of the trouble is located, it is then possi- 
ble to complain to the proper party and thus 
obtain correction most quickly, and inci- 
dentally to avoid unwarranted complaint to 
other parties not responsible for the difficulty. 
If the test described above shows that the noise 
is coming in on the house power lines, the search 
can then be continued. The fact that it comes 
in over the lines does not mean necessarily 
that there is a fault on the power lines. It may 
be caused by some device connected to the 
lines at some point. Or it may be caused by 
the power lines acting merely as collector of a 
disturbance which originates on other wires 
near them at some point. 

Power companies take care of the mainten- 
ance of the lines which supply and distribute 
electric power. Faults on lines themselves, 
which cause radio interference, occur sometimes, 



but such faults make only a small percentage 
of all sources of interference, as shown in the 
table below. Power companies try to maintain 
their lines in good condition, and most lines 
are regularly inspected, so that serious faults 
are likely to be discovered before they have 
existed very long. 

The following table of classes of interference 
caused by electric circuits, is based upon ap- 
proximately one hundred verified reports. 



NATURE OF INTERFERENCE 

Telephone Bell Ringers . 

Gas Engine Plants .... 

Miscellaneous Industrials (Trol- 
leys, motors, rectifiers, signals 
etc.) 

Town lighting plants and street 
lighting . 

Household Appliances 

Power Lines 

Electric Precipitators 



PERCENTAGE OF 
TOTAL CASES 



25% 



17% 

3% 

2% 
10% 

2% 



It should be appreciated by broadcast listen- 
ers that interference may be caused by some 
electrical devices which are in normal working 
order. Examples of such devices are heater 
pads (thermostatically controlled), violet-ray 
machines, trolley cars, store and factory 
motors, elevator machinery, etc. In many 
cases, operation of such apparatus can not be 
stopped for the sake of broadcast reception, 
and unless some of the remedies described in 
preceding articles (RADIO BROADCAST for April 
and May, 1924), can be applied, through co- 
operation of the broadcast listener and the 
owner of the apparatus, the broadcast listener 
should be satisfied with reception of signals 
which are strong enough to dominate the in- 
terference. Exceptional cases of this sort may 
arise, however, where such electrical apparatus 
operation affects the radio reception of a 
sufficiently large body of listeners to constitute 
a public nuisance, and in such cases, special 
remedies may be justified. 



IDE interest has been excited by the RADIO BROADCAST $500 prife contest "Who 
Is to Pay for Broadcasting and How?" Full particulars appeared in the maga- 
for May and June. All entries for the contest must be in the mails by July 20, 
1924, addressed RADIO BROADCAST Who Is to Pay Contest, care American Radio Asso- 
ciation, 50 Union Square, New York City. 




HOW TO BUILD A RADIO "TESTOMETER" 



IT IS often exasperating, or worse, to await 
the opening of a local or particular broad- 
casting station in order to determine 
whether or not a new receiver is operating. 
The radio "Testometer" is a convenient 
name for a small buzzer transmitter that may 
be used to generate radio signals for the test- 
ing and comparison of receiving sets. The 
testometer enables the experimenter to test 
the sensitivity of any receiver by using this 
kind of portable standard, and to determine 
approximately its wavelength range, quite in- 
dependent of S O S's and the caprices or 
operating hours of 
broadcasting sta- 
tions. 

Technically, the 
testometer is nothing 
more than a buzzer 
excited wavemeter 
the accuracy of which 
would send the Bureau 
of Standards into con- 
vulsions. However, it 
is quite adequate for 
the purpose for which 
we recommend it, and 
it is so simple that it 
may be almost thrown 
together in a few min- 
utes, if the experimen- 
ter does not care to 
construct the testome- 
ter as a permanent 
piece of laboratory 
equipment shown in 



Wlat the Lab Offers You This Month 

How to build a "radio testometer" a simply 
built adaptation of the wavemeter which indi- 
cates at once the wavelength range and state of 
sensitivity of your receiver. 
Illustration of commendable super-heterodyne 
construction from RADIO BROADCAST articles. 
How to build a self-supporting loop. 
An illustration of a neat three-tube RADIO 
BROADCAST K nock-Out receiver built by a reader. 
How an audio-frequency transformer may be 
connected, still to perform good service as an 
impedance-coupling for the last tube of your 
audio-frequency amplifier. 
How to build a very inexpensive and very 
stable crystal detector which should be valuable 
in a reflex receiver. 

Results of using the WD-n and WD-12 tubes 
in the RADIO BROADCAST one-tube Knock-Out 
receiver. 
Suggestions for the growing laboratory. 



Figs, i, 2 and 3. The circuit is diagrammed 
in Fig. 4. 

B is the buzzer, preferably of the radio 
type, with an adjustable contact, and vibrat- 
ing very rapidly. Ci is a by-pass condenser 
around the buzzer coils. C2 is a tuning con- 
denser, an active part of the oscillating system 
that eliminates the necessity for a many-turn 
coil at L. Both capacities are fixed Micadons. 
Using a .00025 nifd. condenser at C2, L is 
wound on a three-inch form with twenty turns 
of approximately No. 22 wire, tapped in the 
middle. A three-point switch is mounted 

under the buzzer, giv- 
ing "off" to the left, 
and low and high 
wave on the respective 
points to the right. 
With the suggested 
values of capacity and 
inductance, the circuit 
will oscillate on the 
middle tap at approx- 
imately 1,111 kilo- 
cycles (270 meters) 
and at 667 kilocycles 
(450 meters) on the 
higher wave giving 
a good idea of the 
ability of the receiver 
under test to cover the 
broadcast range. 

Three dry cells, or a 
six-volt storage bat- 
tery are used to actu- 
ate the testometer. In 



Radio Broadcast 



merely testing a receiver, the wavemeter is 
placed on the operating table, alongside of 
the set, as shown in Fig. 3. The testometer is 
operated on either high or low wave, and the 
note tuned for in the receiver. The sound re- 
ceived is not the comparatively pleasing tone 
of the buzzer, but is a rather rasping note, 
sounding somewhat like a poorly adjusted 
spark coil transmitter or the raspings of a 
violet-ray machine. 

The testometer should first be tried with a 
receiver of known excellence, and the contact 
of the buzzer adjusted until the signals are 
most steady and loud. No antenna is required 
for these tests. As a criterion for future 
comparisons, it is a good idea to note how far 
from the receiver the transmitted buzzer signals 
are audible. The testometer is removed from 
the operating table, and carried to other parts 
of the station or home until the signals can 
just be heard i. e., at "threshold" audibility. 
During these tests, the buzzer and its induc- 
tance should be rotated for maximum intensity, 
as the directional effect of the miniature trans- 
mitter is quite noticeable. 

It is now possible to compare the sensitivity 
of any other receiver with your standard set, 
by noting how far from receiver number two 
the buzzer signals can be heard at threshold 
strength. 

A standard announcing buzzer may be used 
in the testometer if the experimenter cannot 
secure the high tone type. 





FIG. 2 
Rear view of the Testometer 



FIG. I 
Front view of the Radio "Testometer" 



SOME EXCELLENT EXAMPLES OF 
SUPER-HETERODYNE AND REFLEX 
RECEIVER CONSTRUCTION 

THE enthusiast does not truly begin to en- 
joy radio until he applies his own ingenuity 
to the problems that inevitably confront him. 
The pleasure derived from operating and dis- 
playing a set which reflects one's own mechani- 
cal or electrical ability far exceeds the merely 
passive pleasure of tuning a receiver that some 
one else has built and installed for you. 

The photographs, Figs. 5, 6, 7, and 8 are 
expressions of original thought in the construc- 
tion and mounting of receivers. Figs. 5 and 
6 are views of the super-heterodyne built by 
E. F. Weber of Chicago, 111., from data pub- 
lished in RADIO BROADCAST. 

Mr. Weber is to be commended, not merely 
on the electrical details, such as individual 
meters, etc., which are evidences of deviation 
from Mr. Haynes' description of his super- 
heterodyne, but for the ensemble the desk- 
cabinet which adequately provides for his 
entire equipment. The B battery is contained 
in the desk compartment, and can be seen in 
the photograph. The storage A battery is 
in the lower left hand cabinet, and just above it 
is the motor-generator charger. 

Particular attention is called to the very 
original construction of the loop aerial. It is 
two feet on a side, and built entirely of rigid 
bus-bar wire. This eliminates the usual cross- 
bars and makes the loop self-supporting. 



In the R. B. Lab 



241 



Three quarters of an inch spacing between 
turns is about right. 

A shortened broom stick may be used for 
the central support. Toward the center of the 
loop, single lengths of bus bar wire will suffice 
for both horizontal and vertical wires but clip- 
ped pieces will be necessary for each of the 
four sides of the outer turns. 

Figs. 7 and 8 show the very neat three-tube 
set built electrically from the description of 
"A Three Tube Knock-Out," published in the 
February RADIO BROADCAST, and mechanically 
from the imagination of the builder, F. W. 
Becker of Gloversville, New York. 

The photographs are self-explanatory. The 
cabinet houses the receiver, B battery and 
loud speaker, the bell of which is directly be- 
hind the burlap screen in the upper right hand 
portion of the photograph. 

The finished instrument is equally worthy 
of a place in a well appointed library, or in the 
radio laboratory. 



AN EFFECTIVE WAY OF USING A 

BLOWN OUT AUDIO-FREQUENCY 

TRANSFORMER AS IMPEDANCE 

COUPLING 

WHEN your last stage transformer suc- 
cumbs to the strain of high voltages, and 
either the primary or secondary becomes 
"open," its usefulness is by no means ex- 
hausted. Utilizing the remaining winding 
as a coupling impedance, the last step circuit 
can be made over into a final stage of impe- 
dance-coupled amplification with very little 
trouble. Though this system may give slightly 
less volume than a transformer-coupled am- 
plifier working with a step-up ratio, the result- 
ing quality is better. 

Most transformer difficulties in audio-fre- 
quency amplifiers can be traced to an open 
in the primary of the last stage. It is this wind- 
ing that is subjected to the greatest strain. 
However, for the purpose of impedance-coupled 




FIG. 3 

Using the Testometer. It may be operated at a distance from the receiver in order to test it for sensitivity 



242 



Radio Broadcast 



amplification, itisimmaterialwhich windingsur- 
vives. If, as it is probable, a perfect secondary 
is at the disposal of the experimenter, the input 
efficiency of the last tube will be high. On the 
other hand, if a primary is employed as the 
impedance coupling, the output efficiency of 
the next to the last tube (or that tube in the 
plate circuit of which the impedance is placed) 
will be at par so the effect is that of an aver- 
age. 

Fig. 9 is the diagram of a two-stage amplifier 
in which the second transformer has broken 
down, and the remaining winding "X" sub- 
stituted for the separate primary and secon- 
dary. C is a combination isolating-coupling 
condenser such as used in resistance-coupled 
amplifiers. Its capacity is preferably .006 
mfd., though .0025 mfd. will work very 
well. R is a grid leak, the resistance of which 
is best determined by experiment. One fifth 
megohm is, perhaps, the average value for R. 
The connection between the minus B battery 
and the filament lighting battery has been in- 
dicated only tentatively by dotted lines. This 
connection will probably be made in the tuning 
or detecting circuit where the polarity is often 
important. The amplifier will operate either 
way. 

The theoretical functioning of the impe- 
dance-coupled intensifier is a cross between 
the action of a resistance-coupled amplifier 
(see the " Knock-Out Four Tube Receiver" 
in the June RADIO BROADCAST) and the 
operation of the transformer-coupled ampli- 
fier. There is, of course, a potential drop 
across X which is applied to the grid of the 
succeeding tube through condenser C as would 
be the case were X a pure resistance. There is 





FIG. 5 
Behind the scenes in a super-heterodyne built by one of our readers 



FIG. 4 

The circuit of the Testometer. It is 
merely a wavemeter with two adjustments 

also a self-induced potential, an auto-trans- 
former action, caused by the rise and fall of the 
magnetic flux about the winding, that is 
similarly impressed on the grid of the last tube. 
Impedance amplification has the advantage 
over resistance coupling in that no higher 
plate voltages are required than are usually 
applied in the conventional amplifying system. 
The quality, as before mentioned, is superior to 
that of a transformer-coupled amplifier. This 
is partly because there is no step-up ratio 
which has the effect of magnifying distortions. 
Also, there are many less turns of highly in- 
ductive winding which have an inherent ten- 
dency to distort. Due to the perfect quality 
of output, impedance-coupled amplifiers are 
used in the Bell system for amplifying tele- 
phone speech. 

The substitution of impedance for trans- 
former-coupled amplification is not, of course, 
confined to the last stage. Three reasons, 
however, recommend it in the final stage. The 
probable transformer b'reak-down in this posi- 
tion makes its substitution a particularly simple 
matter, and the impedance- 
coupled amplifier is much 
more effective when fed 
with the "kick" from the 
first stage of intensification. 
Also, the last step of am- 
plification, where quality is 
especially impaired, is the 
logical position for a stage 
that amplifies with a mini- 
mum of distortion. 

The secondary of a Ford 
spark coil or a telephone re- 
peater coil makes an excel- 
lent coupling impedance 
and might quite well be used 
by the curious experimenter. 



In the R. B. Lab. 



243 



HOW TO MAKE A VERY STABLE CRYS- 
TAL DETECTOR 

FIG. 10 is a photograph of a clever crystal 
arrangement devised by J M. Dock- 
stader of Perth Amboy, New Jersey. It was 
designed for use with the single-tube reflex 
receiver as a compromise between the fixed 
crystal and the adjustable detector. Mr. 
Dockstader's little device possesses the stability 
of the fixed crystal, while permitting the de- 
sirable adjustment of the old-style detector. 
Used in this laboratory, it maintained its sensi- 
tive adjustment for two weeks, during which 
period it was moved about, from shelf to the 
operating table and back again several times. 

Photograph 10 shows the crystal arrange- 
ment mounted on a small individual base 
made of Mahoganite panel material. It can, 
however, be mounted more conveniently on 
the panel or base of the receiving set proper. 
The photograph shows the construction very 
clearly. The size of the 
base is about two inches 
by two inches. 

The prongs may be bent 
from any very stiff wire 
(they are not delicate cat- 
whiskers). The designer 
recommends No. 20 German 
silver. Two and three quar- 
ters inches of wire will be 
enough for each prong. 
Small loops are formed in 
one end, while the other 
end is flattened and cut 
with snips or pliers to a 
spear point. The prongs 
are then mounted in the 
position indicated by the 
photograph (most conve- 
niently with wood screws 
on the base of the receiver) 
so that they meet the crys- 
tal at right angles to its sur- 
face, and with the contact 
points separated not more 
than | inch. The closer the 
points are together, the more 
surface of the mineral there 
is available for exploration. 

The crystal is silicon, not 
galena, and is mounted in a 
small slab of bakelite or hard 



drilled and cut in the insulating strip to a depth 
that will flush mount the crystal, which should 
have a flat surface. A bit of sealing wax is melted 
into the hole and onto the reverse side of the crys- 
tal. While the wax is hot, the mineral is pressed 
into the hole. Two or more crystals may be 
mounted on the single strip as suggested in the 
photograph. 

The tension on the two wires should be about 
equal, and sufficient to hold the crystal firmly 
against the base. The points should follow 
the crystal rather than glide over it when it is 
moved. In some cases it may be of advantage 
to blunt one of the wires. 

The detector is adjusted by moving the crystal 
with the fingers or tapping with a lead-pencil. 

THE WD-I2 AND THE REFLEX SET 

THE designer of the crystal detector 
described above, also sends us some operat- 
ing data on using the dry cell tube in the one- 




FIG. 6 



rubber. An oblong hole is 



A home fit for a super-heterodyne. Note the self-supporting loop 



244 



Radio Broadcast 



tube reflex receiver, which corroborates our 
own experience with these tubes as amplifiers. 
Mr. Dockstader finds that superior results 
are obtained with the WD-n and WD-I2 
when a higher voltage A battery is employed 
with a thirty- to sixty-ohm rheostat. The rheo- 
stat is placed in the negative filament lead, 
while the grid return, through the secondary 
of the amplifying transformer, runs to the 
negative terminal of the "A" battery. As 
Mr. Dockstader suggests, the increase in 
efficiency is due to the bias secured by the 
potential drop across the rheostat. A fixed 
resistance should be substituted for part of 
the extra resistance in order to prevent possible 
burning out of the tube if too little resistance 
is used, such as might well be the case if a rotary 
rheostat were used alone. Equally satisfac- 
tory results can be obtained by placing a 
small C battery, of one and a half to three volts, 




FIG. 7 

An interesting example of original construction 

negative to the grid, between the lower sfde 
of the transformer secondary (T3 in all of our 
single-tube reflex diagrams) and the negative 
of the filament battery. 

WHERE TO BUY INDIA INK 

HIGGINS White Label India Ink, such as 
was used in the home manufacture of grid- 
leaks described in the R. B. Lab a number of 




FIG. 8 



A RADIO BROADCAST circuit plus 
the ingenuity of the builder 

months ago can be bought from any large sta- 
tionery store handling artists' supplies. How- 
ever, experimenters living in small towns may 
find it rather difficult to obtain through a local 
dealer. It is suggested that readers having dif- 
ficulty in securing this particular grade of ink, 
order direct from Brentano's, Fifth Avenue and 
27th Street, New York City. Thirty cents is 
the postpaid price for a small bottle enough 
for a hundred grid-leaks of varying resistances. 

LEAVES FROM AN OLD TIMER'S 
NOTEBOOK 

ELECTROLYTIC RECTIFIERS: In us- 
ing electrolytic rectifiers of the lead- 
aluminum type for the rectification of A. C. 




FIG. 9 

How to use an amplifying trans- 
former with a blown out winding 



In the R. B. Lab. 



245 



for the plate potential in bulb 
transmission, or for the charging 
of storage batteries, a slight purple 
haze about the metal elements, 
more noticeable in the case of high 
voltage rectification, is an indica- 
tion of perfect operation. Defective 
rectifiers are characterized by spark- 
ing and general pyrotechnics in cer- 
tain jars. This, as is understood, 
necessitates a replacement of jars, 
but be sure and replace the jars 
that do not spark. Those that spark 
are the good jars, and spark only 
because they are overloaded by the 
inoperation of the inactive cells! 

BUILDING YOUR OWN LAB 

ANOTHER month rolls by, and 
the lab is growing. RADIO 
BROADCAST suggests for July a set 
of "Spintite" wrenches. These 
wrenches may be purchased singly, 
in various sizes, but are most con- 
veniently obtained in the standard 
set of seven as shown in Fig. 1 1 . 

The Spintite wrench is used in 
place of the usual flat wrench, but 
works much faster with a screw- 



I 





FIG. I I 
A handy set of wrenches for the laboratory 



driver motion. Two handed co- 
operation of- screw-driver and 
wrench insures well spun nuts that 
will not vibrate loose when ad- 
vanced construction makes access 
to them difficult or impossible. 
The intelligent use of these tools 
will slice many minutes, and some- 
times hours, from a difficult assem- 
bly job. 



FIG. 10 

An interesting and simple detector 
It is almost a "fixed" crystal 



CUT some No. 14 bare copper 
antenna wire into five-foot 
lengths. Twist one end of a length 
around a nail permanently fastened 
and place the other end in the chuck 
of a hand drill. Then, with a steady 
pull, turn the handle of the drill first 
in one direction and then another 
for a few turns. A stiff piece of 
round wire, far cheaper than the 
" store " bus wire, results. 



Broadcasting Personality 

How S. L. Rothafel, Better Known as "Roxie," Brings the Human Touch 
to Radio in His Famous Sunday Evening Capitol Theatre Concerts Sent from 
WEAF, WJAR, and WCAP. Is "Roxie" the Anticipated Genius of Radio? 

By JAMES C. YOUNG 



WHAT does the radio public 
want? 
" I don't know." 
Such was the answer of 
S. L. Rothafel, one of the 
most successful impresarios of the air. Sitting 
at his big desk in the Capitol Theatre Build- 
ing on Broadway he confided some of the 
troubles which beset a radio director. 

"No general reply will answer your ques- 
tion," he said, "but perhaps we can state the 
matter a little differ- 
ently. It is the per- 
sonality of the per- 
former that sways or 
fails to sway the 
great unseen audi- 
ence distributed over 
thousands of miles, 
but drawn together 
in a common thought 
by the pulsations of 
the air. 

"This is the most 
appreciative audi- 
ence in the world and 
also the most critical. 
Above all else, it is a 
sincere audience, and 
accurately measures 
the human quality of 
the performer before 
the microphone. 

" When a man be- 
gins to speak, let us 
say, the audience in 
his vast theater in- 
stantly divines whether he knows his subject, 
whether he merely is speaking in the profes- 
sional sense, or sends words worth while across 
the reaches of space. If the man is sincere, 
moved by high purpose, his audience hands over 
its confidence; if he is prosaic, indifferent, just 
talking to kill minutes, his audience is likely to 
tune-out with one accord. 




THE PIPE AND ROXIE 
S. L. Rothafel in an unaccustomed moment of repose. 



fairly vibrates his personality through the microphone Sunday 
nights when he and his gang are on the air through WEAF, 
WCAP, WJAR 



" I am convinced that the radio performer's 
personality is more important than his voice, 
his subject or the occasion. Any of these may 
be poor or inopportune and still a speaker will 
succeed. But if his personality is flat, his 
purpose vague, he certainly will not command 
respect on the radio circuit." 

Mr. Rothafel has a trick of catching one 
knee in two strong hands, then whirling this 
way and that in his swivel chair, as he talks. 
It is not difficult to see why he has caught the 

imagination of radio 
audiences. He has a 
sparkling eye and a 
moving vitality that 
impart confidence 
and enthusiasm. His 
Sunday night pro- 
grams broadcast 
from WEAF, WJAR, 
and WCAP, are 
awaited by radio 
owners everywhere. 
Certainly there is 
nothingof thecasual, 
hit-or-miss quality 
about these pro- 
grams. They have 
all the finesse, the 
completeness and 
satisfaction of a the- 
atrical performance 
that just strikes the 
nail of public favor. 
"Sometimes when 1 
am in a radio studio 
waiting for our turn 1 
study the effects of personalities unknown to me, 
at the moment they come in contact with the 
public," said Mr. Rothafel. "There is some- 
thing psychic about the result. The same 
waves of the air which are carrying away the 
words or music of the performer or other 
waves of much the same sort bring back the 
reflection of the public mind. An experienced 



Roxie 



Broadcasting Personality 



247 



observer can sense in a minute or two whether 
the performer is succeeding. And without 
exception I would say that the big factor is 
personality, no matter what the medium of 
expression." 

"Can't you apply that psychic sense in ad- 
vance and decide whether a performer will 
succeed or fail?" 

" I hope you will not think me boastful," 
said Mr. Rothafel," but I never offered more 
than one number 
which failed. And 
that was my fault. I 
did not present it 
properly." 

The Capitol com- 
pany known to fame 
as Roxie's Gang in- 
cludes more than 
thirty-five performers 
and his programs range 
all thewayfromthe se- 
verely classical to "Sally in Our Alley." Be- 
tween times these programs dip into philosophy, 
poetry, folk lore, and musical compositions of 
every possible shade. But the presiding genius 
of this company and these programs is his own 
most popular performer. The typical Rothafel 
prelude, introductions and final "Good night," 
are awaited weekly by an expectant host wher- 
ever the far-flung radio waves travel. 

The next time a reader hears one of those 
programs, let him employ his imagination a 
bit and transport his psychic self to the studio. 
Here is the microphone, everything is ready, a 
girl singer steps up to the instrument. Now 
just observe the impresario. He raises a 
finger, the girl watches his face, and at the 
sign of an eyelid she begins to sing. 

HOW ROXIE TURNS ON THE PSYCHIC TAP 

A) THE first notes rise Mr. Rothafel 
"registers" for her benefit how she is 
getting on. Her eyes never leave his face. 
A wag of the head, a shake of the finger, a 
change of expression, govern her efforts. For 
the moment the director is her audience, taking 
the place of all that multitude, perhaps listen- 
ing to some old ballad. Mr. Rothafel is no 
mean actor. He conveys to the girl every 
emotion which she stirs. He has a plastic, 
expressionable face; for the moment his 
own personality drops away. He literally 
is the audience, sensing just how it feels, 
and as the girl goes on he carries her over 



" 1 am convinced that the radio per- 
former's personality is more important 
than his voice, his subject, or the occasion. 
Any of these may be poor or inopportune 
and still a speaker will succeed. But if 
his personality is flat, his purpose vague, 
he certainly will not command respect on 
the radio circuit." ROXIE. 



every bad spot in the road if there happen 
to be any. 

Perhaps her expression is a little over-drawn; 
maybe the pathos is a trifle too deep. Right 
there the director shakes his head and frowns 
and the expression comes down a key, into the 
more natural, easy mode which is needed. If 
the girl were singing by herself on her own, so 
to speak she never would know that she had 
reached a little too far, that her technique had 

faltered. But with a 
director at her elbow 
who literally turns on 
the psychic tap and 
interprets for her how 
the audience responds, 
she has a valuable aid 
to genius. 

Still Mr. Rothafel 
says that he cannot 
gauge what the public 
wants. That state- 
ment is no gesture of modesty; he means to im- 
ply that the public wants many things at many 
times. 

"It is deceptive to speak of the public 
taste," he said. "We have to consider the 
individual tastes of a great audience we never 
see. Every person in that audience, if asked 
the question, would express a different opinion 
about any number suggested, or any subject. 
Therefore we must try to unite all of these 
minds on themes which touch their imagina- 
tion." 

Mr. Rothafel is a bit of a seer when he is not 
directing programs. Philosophic observations 
stand forth from his speech. Here he in- 
dulged in an analysis of the public mind. 

" Imagination is the greatest power in the 
world," he said. "It is the thing that moves 
mountains and captures audiences. The 
public has a quick, sympathetic imagination. 
We hear a great deal about what the public 
wants and what it does not want. Once in a 
while the public has a chance to choose for it- 
self and the choice is always well made. This 
public of which we hear so much has more 
intelligence and good taste than it is usually! 
credited with having. There is one secret 
route to the public heart first, be sincere; 
then lay hold of its imagination." 

This emphasis on sincerity cropped out several 
times in Mr. Rothafel's conversation. "We 
have taken the radio seriously," he resumed. 
"As yet I do not believe that its potentialities 



248 



Radio Broadcast 



are understood. It is in a fair way to become 
one of the greatest mediums of public inter- 
course. Radio furnishes a similar parallel to 
moving pictures. As the film performance was 
an extension of the drama, so the radio widens 
the possibilities of the spoken word. It 
brings a speaker or performer in contact with 
an audience so much greater than we ever con- 
ceived of before that one man's power of com- 
munication is infinitely magnified. 

WHAT RADIO CAN DO FOR OUR SENSES 

IB ELI EVE that the radio will give us a new 
appreciation of what language means. In 
many ways it is the most elastic medium of 
speech. When we go to a theatre or a public 
address virtually all of our senses are put to use. 
We see the speaker or dramatic spectacle, we 
hear the words or music, we are comfortable or 
otherwise. Each faculty is employed in some 
way. The radio audience, seated quietly 
in its thousands of homes, employs but one 
sense. All of its faculties are concentrated in 
listening, probably the simplest of all our 



conscious efforts, simpler even than the use of 
sight. Few distractions affect the radio audi- 
ence. It is at ease. The whole power of its 
collective intelligence centers in the sound 
waves which converge in the receiving instru- 
ments. Therefore a performer receives a 
fixed attention impossible to obtain in any 
other way. For that reason his audience is 
more critical, more understanding. It com- 
prehends his personality fully and accurately. 
Its sympathy is whole-hearted when he can 
command it. Sometimes 1 have asked audi- 
ences to listen in darkness to our programs. 
The effect is heightened until the man a 
thousand miles away is in just as intimate con- 
tact with us as if he stood in the same room." 

When the Capitol company achieved its con- 
tinued success many cities and organizations 
invited Mr. Rothafel and his artists to appear 
in public. That raised a nice point of psycho- 
logy. 

" 1 was doubtful about the result," he said. 
" Every person familiar with our radio pro- 
grams had a conception of how we looked and 




"ROXIE".AND HIS CAPITOL THEATRE GANG 

\\ ho broadcast each Sunday evening from WEAF, New York. These are thirty-five of the most popular entertainers 

on the air; they are: 

TOP Row: Clark Robinson, Alfred Lufrio, Joe Wetzel, James Parker Coombs, Pierre Harrower, Victor Arden, Phil Ohman 

THIRD Row: Carl Scheutze, Alex Cluck, Hyman Barmasch, Attilio Bianco, Chas. Thetford, David Mendoza, Ignace 

Nowicki, Herman Hand, Robert Denti, Louis Schmidt, William Roeschell. 

SEATED: TOP Row: Ava Bombarger, Marjorie Harcum, Gladys Rice, Evelyn Herbert, S. L. Rothafel ("Roxie"), Betsey 

Ayres, Marguerite McKee, Florence Mulholland, Eugene Ormandy ("The Blue Blond"). 

SEATED, BOTTOM Row: Yasha Bunchuk, Tommy Dowd, Douglas Stanbury, Maria Gambarelli ("Gamby"), Susan 

Dunbar, Bully Robyn ("Wee Willie"), Dr. William Axt ("Dr. Billy"), Alex Kosezgi 



Broadcasting Personality 



249 



acted. 1 1 might bea severe strain on their friend- 
ship to see us in life. We fully comprehended 
that we were just ordinary folk like everybody 
else. Our radio entertainment was the best 

thing we could do, our 

finest efforts. We had 
put intothework all of 
ourhopes and enthusi- 
asm. When the public 
saw us it might think 
we were a very ordi- 
nary crowd, after all." 

But insistent re- 
quests brought an ex- 
periment. The Capi- 
tol cornpany began to 
appear in public. And 
no company of enter- 
tainers in the world 
ever had a finer recep- 
tion. So far these ap- 
pearances have been 
few, notably in Provi- 
dence and Pawtucket, 
R. 1., and Washing- 
ton, D. C. 

"On the way over 
to Providence, we 
found that everybody 
knew us," said Mr. 
Rothafel. "Our pub- 
lic acquaintance began 
with the sleeping car 
porter. He addressed 
a half dozen of our 
performers by name 
just as intimately as 
though they had been 
friends for years. 

"When we got to 
Providence the word 
of our coming had pre- 
ceded us. I never had 
such an experience. A 
newsboy came up to 
me in the station and 
said, 'Gee, Roxie, that 
was a great bill you 
had last Sunday, and 
the story you told sure 
was a whopper.' 

" Everywhere we went in Providence, people 
seemed to know us, first names and all. We 
were scheduled to appear there in a large store. 
When the time came a crowd filled the streets 



This bit of verse was written 
by J. P. (Daddy) Coombs and 
was read on the air by Mr. 
Rothafel after he and his Gang 
had made a visit to the Walter 
Reed Veteran's Hospital in 
Washington. "Roxie" is 

bringing all of his considerable 
radio influence to bear to 
secure contributions from his 
radio listeners to equip vete- 
rans' hospitals with radio re- 
ceiving sets. 

When darkest night 

Falls on our sight 
And Life seems dull and gray 

Remember friends 

That nature sends 
The night to follow day. 

Then do not grieve 

When dewy eve 
Shall change to night's black patt 

The breaking dawn 

At glorious morn. 
Will gladness bring to all. 

When shadows loom 

From out the gloom 
This truth you'll surely find 

Turn toward the light 

Its radiance bright 
Will leave all gloom behind. 

A kindly word 

Is gladly heard 
And treasured in the heart 

A bit of song 

Remembered long 
By friends tho' far apart. 

So " There you are" 

Friends near and far 
Good night. Good night to all 

You've heard the song 

May joy prolong 
Its echoes wher'ere they fall. 



for blocks, everybody from mothers with baby 
carriages to staid business men. And they 
had such a welcome for us that we felt as if 
each one was our personal friend. It was a 

touching thing; it 
made us realize that 
we had a great respon- 
sibility to the public; 
that we must do bet- 
ter than ever before if 
we possibly could. 
The esteem of those 
good people was the 
finest tribute any of 
us ever had. We left 
Providence resolving 
that we would put in- 
to our radio programs 
the best of our hearts 
and minds." 

The Capitol com- 
pany raised $3,500 in 
Providence for a char- 
itable purpose, a com- 
fortable sum in Paw- 
tucket, and more than 
Si 0,000 for the Walter 
Reed Hospital in 
Washington. Mr. 
Rothafel and his asso- 
ciates hope to obtain 
radio receiving sets 
for all the veterans 
in Washington hos- 
pitals. 

The affection of ra- 
dio fans is boundless. 
Every day or two the 
Capitol company re- 
ceives evidence of this 
regard. A group of 
citizens in Attleboro, 
Mass., got together 
and sent the director a 
silver loving cup, by 
way of expressing their 
good will. It is a dull 
day in the Rothafel 
offices when a crate of 
oranges fails to arrive 
from Florida or some 
other token sent by friends far and near. 

Each new form of entertainment, of the 
dramatic appeal, has brought with it the 
rise of some man who comprehended its 



2 SO 



Radio Broadcast 



possibilities. Perhaps Mr. Rothafel is to be 
the genius of the radio. His efforts, and the 
efforts of his company, have caught the public 
fancy in a more pronounced way for a longer 
period than the efforts of any other group or 
individual. Radio programs still are a matter 
of much uncertainty. No station in the coun- 
try has been able to decide what the public 
wants and Mr. Rothafel says he doesn't know. 
But evidently the public knows and his guesses 
about its state of mind are remarkably accurate. 

ROXIE'S PROGRAMS ARE EXPERIMENT 

T OOK1NG over the Rothafel programs it is 
L, evident that he believes in variety; also 
that each program is something of an experi- 
ment. One of his recent successes was the 
offering of "Massa's in the Cold, Cold Ground." 
That is a song which but few Americans of this 
generation ever heard. It came from the pen 
of Stephen Foster, author of the many negro 
melodies which gradually have become Ameri- 
can classics, perhaps our only distinctively 
American songs. 

Mr. Rothafel, with the same sure instinct 
that prompted Foster to write the song, de- 
cided to test its possibilities by radio. Any 
one who has heard these plaintive notes will 
recall that it is sung almost in a monotone and 
is especially suited to a mellow voice. 

When the singer in this case stepped up to 
the microphone Mr. Rothafel waited with 
considerable anxiety for the results from his 
psychic contact. But the song had not gone 
beyond the first bars until he signalled "all's 
well." Then, toward the end, he took the 
singer's arm and together they walked across 
the studio, the last melancholy notes gradually 
blending with the air that insubstantial ele- 
ment which had just borne to an awed audience 
the story of an old slave's sorrow that his good 
master should lie "in the cold, cold ground." 

It requires but little acumen to see that Mr. 
Rothafel is the sort of man who has studied 
life at close range. He was born on a Minne- 



sota farm back in 1882 and reached New 
York at the manly age of thirteen. Soon he 
was employed as "cash boy" in a Fourteenth 
street store. But he lost the job because his 
employer thought he had too much imagina- 
tion, that he was always dreaming. Since then 
he has changed his job pretty regularly; every 
time it became narrow and cramped him he 
struck out anew, until he is directing head of the 
world's largest motion picture theatre and the 
leading producer for radio audiences. 

He has had a wide range of jobs between the 
two extremes. These included the work of a 
book agent and a Marine. He has knocked 
around the world and rubbed shoulders with 
all sorts and conditions of men. Doubtless 
that is why he understands the genus so well. 
He really got his start in a little Pennsylvania 
town with a second-hand moving picture ma- 
chine and a few chairs in an upstairs room 
reached by way of an alley. 

Although without technical musical education 
this impresario directs orchestras by the sense 
of feeling, arranges all of his musical selections, 
devises scenic and lighting effects, and does a 
dozen other things that are supposed to re- 
quire the strictest sort of technical training. 
He long since proved that he understood the 
public mind better than most men and his 
later success with radio programs has greatly 
broadened his field of effort. 

Working twelve hours a day, despite all these 
honors, Mr. Rothafel continues to maintain 
the common touch. An usher in his theatre 
said that he was "a regular fellow" and the 
elevator man thought the same thing. He 
looks only moderately like his photographs, 
because they show him in repose and he is 
always in action. He smiles, frowns, relaxes, 
concentrates, gets out of his chair and sits 
down again, with a regularity and rapidity 
that show the speed and sweep of his mental 
range. 

And at 42 he says that he is just getting 
ready to do some real work. 



ILL] AM H. CARY, JR. has written a tremendously interesting story telling 
what is the latest in radio from Paris and the provinces. He has been in France 
for several months listening-in and talking with radio men everywhere. The article will 
appear in an early number of this magazine. They are busy with radio in France, 
and it is not uninteresting to know "what the other half thinks." 



HAYNES 
, SUPER-HETERODYNE 




ONE OF THE UNITS IN THE FARADh 

This super-heterodyne, which is the one described in RADIO BROADCAST last Jan- 
uary, is bringing in WOO, Philadelphia, on a loop on Forty-Third street, New York 

When Radio Replaced the Brass Band 

How New York Radio Dealers Organized a Novel Band-less but not Music-less Parade 

BY WENDELL BUCK 



CAN you imagine a real, honest- 
to-goodness parade without brass 
bands? No. And neither could 
we until a few weeks ago we saw 
a truly wonderful parade without 
a single band in it. But don't mistake us: 
there was music, and lots of it. 

Some weeks ago the New York Edison Com- 
pany held an electric truck parade down Fifth 
Avenue.- More than four hundred electric 
vehicles of almost every conceivable size and 
appearance lined up at Fifth Avenue and Six- 
tieth Street for the parade. Loops, loud 
speakers, and receiving sets were installed on 
many of the trucks. Neutrodynes and super- 
heterodynes were prominent, particularly the 
"supers," which certainly did themselves 
proud so far as supplying good, clear music for 
the parade was concerned. 

The Super-Heterodyne built by the RADIO 
BROADCAST Laboratory was there in all its 
glory. Before the parade started, WOO, 



Philadelphia, came in on a loop loud enough 
to be heard half a block away, despite the 
heavy rumble of city traffic. Later KDKA 
came in fully as loud as WOO. 

A hundred odd spectators gathered for the 
informal morning concert from Philadelphia, 
clustered about the truck, and asked the wide 
variety of questions which only real radio fans 
can ask. 

By two thirty all the trucks were lined up 
with their many loud speakers pouring forth 
plenty of music to supply ample atmosphere for 
the parade. 

A few minutes and they started down the 
Avenue. 

Thousands of pedestrians stopped, looked, 
and listened. Several thousand more came 
pouring from the side streets and stores along 
the way. 

Whenever the trucks stopped for a moment 
which was seldom a good-sized group gath- 
ered around each truck to see just what was 



252 



Radio Broadcast 



going on, and to try to 
complete their radio 
education. 

Everybody in the 
parade was happy un- 
til the trucks reached 
certain more or less 
untravelled streets in 
Greenwich Village. 
Then the RADIO 
BROADCAST super had 
its acid test, and 
emerged victorious. 

After standing the 
wear and tear of, let 
us say, five thousand 

cobblestones, the five thousand and first 
proved too much. The R. B. super with 
its loop fell three feet to the floor of the 
truck. And, believe, it or not, it worked just 
as well (possibly a bit better) during and after 
the disaster. 

However, we hardly suggest dropping your 
own set from anything higher than a book case. 

WHERE THE RADIO DEALER COMES IN 

FROM the point of view of manufacturers 
and radio dealers, the parade was particu- 
larly successful. It put radio before the New 
York public in a novel and impressive way. 
Thousands who had merely a casual acquain- 
tance with radio, who had a vague desire to 
know more about it, or even were on the 
point of purchasing a set, must have been 
brought a step or two closer to a purchase 
when they saw the truck parade roll down the 



Here's a Good Idea 

A thing of interest and novelty itself, there is 
little more of novelty which can be brought to 
either selling or owning radio. Radio has def- 
initely arrived at the stage in its development 
where it has cast off the knickerbockers of novelty 
and assumed the long trousers of stability. 
Radio has arrived. But there are always gen- 
erous quotas of doubting Thomases in every 
sizeable community whom the radio dealer ought 
to convince. A parade, such as Mr. Buck de- 
scribes would be as interesting to the spectator 
as effective for the dealer. THE EDITOR. 




Avenue. And many 
a skeptic regarding 
radio must have been 
converted on the spot. 
Think of it! Seventy- 
five radio sets mount- 
ed on electric trucks 
rolling over rough 
streets and supplying 
uninterrupted music 
all the way. And these 
were not only local 
programs, but distant 
ones as well. 

The Edison Parade 
certainly did radio a 

great deal of good. It didn't make people rush 
to the nearest radio store to buy a set. But it 
sold the practicality of radio to thousands of new 




Courtesy New York Edison Company 
THE PARADE AT REST 

Lined up on Fifth avenue alongside Central Park. 

Signals were poured wholesale from the large loud 

speaker for'ard on this well arranged Sleeper truck 



Courtesy New York Edison Company 
READY TO ASTOUND THE NATIVES 

A neutrodyne truck in the radio 
parade swinging into action 

prospects. The next time Mr. So and So, 
who saw the parade, passes a radio store, he 
will undoubtedly drop in to hear the various 
sets demonstrated and he will probably end 
in purchasing one. 

Radio dealers and manufacturers should 
profit by the New York example. Why not 
hold a radio parade in your city? It is sure 
to arouse widespread interest; and if properly 
managed should be the talk of the town. 
Local newspapers will be only too glad to give 
so novel an event considerable space. And 
there is no reason why the articles shouldn't be 
well illustrated. 1 don't see any reason any- 
how for radio and radio dealers hiding their 
light under a bushel. 



How the Radio Voices Look 



WGY 



WOC 



WLAG 



WFI 




AT WOC 

Is Frank W. Elliott, manager 
and occasional announcer of this 
widely heard and popular station 




AT WLAG 

Is Eleanor Poehler, who 

announces and directs 

its radio destinies 



AT WFI 

Is John Vandersloot, 

announcer and studio 

director 



AT WGY 

Is this battery of announcers; they are: 

FRONT Row, left to right: Robert Weidaw, Kolin Hager (chief announcer), Carl Jester; 
BACK Row: William Fay, Asa O. Coggeshall and Edward H. Smith 



How to Build a Good Low-Power 

Transmitter 

Using Standard Parts and Good, Yet Not Expensive Methods of Construction 

BY ASHLEY C. DIXON 



This set was built by Mr. Dixon on his ranch at Stevensville, Montana and is known to 
radio listeners as KFJR on broadcasting, and yIT, and yXAF on code work. Amateurs 
who are interested in building a small transmitter for code and voice should have no 
difficulty in duplicating Mr. Dixon's transmitter. RADIO BROACAST readers will recall 
"What Radio Means At a Rocky Mountain Ranch," by Mr. Dixon in this magazine for 
January. THE EDITOR 



E- i "SHE 
non 
hov 
mit 

A. ran 



following article describes in as 
non-technical language as possible, 
how to build an all-purpose trans- 
mitter of low power and exceptional 
range. By all-purpose transmitter 

is meant one which may be used for amateur 

CW telegraphy, ICW or modulated buzzer, 

phone, as well as for broadcasting. This trans- 
mitter uses two 5-watt 

tubes, giving an actual 

outputof about 1 5 watts 

on CW and 6 on broad- 
cast. No attempt is 

made to go into theory 

or technical details, nor 

into alternative designs 

or substitution of parts. 

It is taken for granted 

that an exact duplicate 

of yIT-KFJR is to be 

constructed by a person 

with enough knowledge 

of radio transmitters to 

permit his holding an 

amateur license. 

Three pictures of the 

panel assembly are 

shown, Figs, i , 8, and 9, 

one of the 50 -henry 

choke, Fig. 4 showing 

comparative size and 

details of construction, 

and one of the trans- 
mitting room showing 

location of batteries, 

switches, etc. There is 




a panel diagram, Fig. 3 one of the top stage, 
Fig. 7, another of the base, Fig. 10 and the 
hook-up, Fig. 2, which many readers will in- 
stantly recognize as the Hartley circuit, with 
Heising modulation system for telephone. 

The panel may be selected from any one of 
the several kinds of panel material now on 
the market. The writer used mahoganite. 

The dimensions are 12" 

x 20" x f ". This panel 
should be strengthened 
by some strips of f " x |" 
maple around the sides 
and top edge. Fasten 
these strips by f " brass 
screws. 

The base is I2"xi4", 
as is the "top stage" 
upon which will be seen 
the oscillation trans- 
former, tubes, etc. 
These two platforms 
should be of some sub- 
stantial hard wood 
aboutf" to i "in thick- 
ness. Fasten them se- 
curely to the panel with 
i" brass screws, and 
brace in the rear with 
maple strips as shown in 
the pictures. You now 
have the frame upon 
which to assemble 
everything but the filter 
system, and power sup- 
FIG. i ply. 



How to Build a Good Low-Power Transmitter 



255 



WHAT GOES ON THE PANEL 

STARTING in the upper left-hand corner 
of the panel, we find the antenna am- 
meter. This should be of the thermo-coupled 
type, and have a scale range from o to i^ 
amps. In the diagram this instrument is 
indicated at A. In the right corner is a filament 
voltmeter, having a scale of o- 1 o volts DC. This 
voltmeter is cut into either tube circuit by a 
series-parallel switch, both instruments being 
represented in the drawing at V with the switch 
just above. The connections as shown permit 
the voltmeter to be cut out at the vertical posi- 
tion, cut into either tube circuit by turning to 
the left or right. In the center is the miHiam- 
meter, used to indicate the plate current flow. 
It is represented at M. 

These instruments are flush-mounted and 
gonsiderable care should be exercised in cutting 
the holes for them. The writer drew circles 
of the proper diameter, and then cut them 
out with a hand bracket saw, using ordinary 
scroll-saw blades. The job is fairly easy if one 
does not try to hurry it. Just below the top 
stage, are located the filament rheostats, the 
knobs of which can be seen in the front view. 
These are RCA Model PR-5 3 5 instruments, and 
are marked on the diagram. They must be 
placed in the positive filament lead. 



Below the rheostat knobs, and between the 
two dials can be seen two screws. These hold 
the inductance L2, which is a 5O-turn 
Giblin-Remler coil, and which is back panel 
mounted. This inductance, together with the 
variable condenser C2, is used to control the 
modulation when the set is used for telephone 
work. We will return to them later on. 

The dials control two .001 mfd. (43-plate 
variable condensers. Any of the better srt 
of receiving condensers may be used. Ci 
is in series with the counterpoise lead (left 
dial), and is used for wavelength adjustment 
when working below 220 meters. For broad- 
casting (258 meters at KFJR) this condenser 
is cut out by a series-parallel switch which may 
be seen mounted on the side of the top stage 
in the pictures, but which is not indicated in 
the schematic drawing. However, wiring in 
this switch is a very simple matter. 

C2 is the above mentioned modulation con- 
. denser, and should have a vernier adjustment 
as a very fine graduation of capacity is neces- 
sary for securing the best modulation and 
radiation when using the set for telephone 
transmission. 

Below the dials are three jacks. The center 
one is a "closed circuit" jack into which is 
plugged the key connection. The key circuit 
is indicated at K in the drawing. The key is con- 




FIG, 2 



256 



Radio Broadcast 



nected in for CW work with an ordinary plug. 
The jack at the left is used to connect a head- 
set into the microphone transformer circuit to 
check up on the volume as shown at MT in the 
diagram. The microphone F is plugged into 
the right hand jack which leads to the primary 
of the microphone transformer. This is a RCA 
Model UP-4I4, and is indicated at MT. 

THE PARTS USED 

ON THE top stage are located the two 
5-watt tubes, the grid inductances LJ 
and 14, the fixed condenser Cj, and the oscil- 
lation transformer Li. The last is a most 
important item since an otherwise good trans- 




FIG. 



mitter may be ruined by a poor transformer. 
The one used here, and recommended, is the 
RCA Model UL-ioo8. It has the lowest 
capacity losses of any type of transformer 
known to the writer. 

The condenser Cj is a model UC-ioi4 
Faradon, having a capacity of .002 mfd. and is 
intended to stand voltages up to 3000 DC. 

The tube sockets are placed in front of the 
oscillation transformer, and are spaced on 6" 
centers. On either side of each tube is located 
a small grid inductance, Lj and 1_4 in the dia- 
gram. Here we come to the first piece of home- 
made apparatus. They are made by winding 
20 turns of No. 28 enameled wire on short 
sections of pasteboard tubing if" in 
diameter. The tubes are mounted 
on a couple of wood spool ends, 
screwed to the stage; and the coils 
connected into the grid circuit as 
I shown. 

Next comes the base on which are 
mounted the following items, all of 
which can be seen by consulting the 
two side views of the set. At the 
back are placed five small No. 4156 
Burgess B batteries. These func- 
tion as grid bias or C batteries, 
maintaining a negative potential on 
the modulating grid. There is prac- 
tically no current drawn from these 
batteries, and they will last a long 
time. 

On the right side of the base is a 
small double - pole double - throw 
switch, used to change over from 
CW to telephone. In the first in- 
stance the tubes are connected in 
parallel, and in the second, one will 
act as modulator and the other as 
oscillator. This last hook-up of the 
tubes provides for what is known as 
the Heising or constant current sys- 
tem of modulation, which is, in the 
writer's opinion, by far the best 
system known to-day. This switch 
and its five connections will be noted 
just below L2 in the drawing. 

In the center of the base is the 
modulation transformer, referred to 
above as MT, and on the left are 
located two UC-io 1 4 Faradon trans- 
mittingcondensersof .002 mfd. each; 
also two transmitting grid leaks 
made by the Radio Corporation and 



How to Build a Good Low-Power Transmitter 



257 




FIG. 4 

listed as UP-iyig. They have a resistance of 
5000 ohms each. The condensers are dia- 
grammed as 4 and 5, and the leaks as Ri 
and R2. 

One more item of especial value is R3. This 
is an ordinary grid leak of i| megohms resis- 
tance, and is of a considerable value in clearing 
up the modulation of music and speech. It is 
shunted directly across the secondary of MT. 

Use ordinary No. 14 hard drawn copper 
wire for all connections, and cover with a 
good grade of oiled cambric spaghetti. Use 
rosin for flux, and have a good connection at 
every soldered joint. 

There are six terminal connections to be 
brought out, two for the an- 
tenna and counterpoise, two 
for the filament battery, and 
two for the plate current sup- 
ply. These may be conveni- 
ently located by mounting a 
couple of small pieces of panel 
on the side and rear of the top 
stage, and soldering the several MAST 
connections to binding posts 
screwed into .these. 



Next in order, and quite important from 
a telephone standpoint, comes the filter sys- 
tem. The inductance in this filter also acts as 
a plate circuit reactor, keeping the plate cur- 
rent supply constant a most essential item 
for the Heising modulation system. 

BUILDING THE CHOKE COIL 

THE picture of the 5O-henry choke coil 
(5oH) gives a good idea of the size and 
construction of this item. It is made by 
winding 12,000 turns of No. 30 enameled wire 
in the form of pies, 1000 turns to each pie. 
These are wound on a \" wide, and if" di- 
ameter square wood spindle, which is fastened 
to a thin flat board about 3" square on one 
side, with a similar piece clamped to the 
other side, so it can be removed to facilitate 
taking off each coil as wound. The spindle 




FIG. 5 

and side-boards are mounted on a shaft of 
some sort (a \" bolt will answer nicely) and 
turned with a crank. It will materially aid in 
removing the pies of wire if a single layer of 
string is wound on the spindle before each 
winding is started, and then pulled out after 
the side plate is removed. 

Each coil, as removed, should be carefully 
wound with insulating tape capable of stand- 




no. 6 



2 5 8 



Radio Broadcast 



FIL:BI PL. e. 



COUNTE 

POISE 




FIG. 7 

ing twice the potential delivered by the 
.dynamotor. 

The core of the choke is built up of thin strips 
of silicon steel, alternating long and short 
pieces on each side, so that the finished job 
will be of an even diameter at the corner joints, 
with the sides. The built up core should have 
a cross section diameter of i ". The thickness 
of the laminations is of no particular note, 
except that for convenience the gauge of the 
metal should permit of its being easily cut 
to size with a pair of tin snips. The pies of wire 
are next slipped upon the steel core, and con- 
nected up in series, terminating at two binding 
posts. Four appear in the picture, but only 
two are used. 

A very necessary feature in the core construc- 
tion is the air gap which will be noticed at the 
top of the core. This should have an opening 
of half an inch, or slightly over. The com- 
plete inductance may be mounted as shown, or 
in any way that suits the ideas of the builder. 
The frame should be of hard wood. 

A technical description of the 50 henry choke 
is given by Ballantine in his Radio Telephony 
for Amateurs*, page 178. With the exception 
of using 500 turns less of wire, our choke is a 
copy of the Ballantine choke. 

The other part of the filter system is simply 
four i mfd. condensers (Faradon UC-49O) 
placed in parallel directly across the generator 

*Pub!ished by David McKay. Philadelphia. Pa 
Price $2.00 net. 



terminals. These are noted as C6 in the dia- 
gram, and their relative position with refer- 
ence to the choke can be seen. In the general 
view of the station it might be noted that 
the choke and condensers are placed in a box 
behind the switch panel, and directly under 
the transmitter. 

The last item to complete the indoor part 
of the station is the power source. The plate 
supply is derived from a 500 volt DC Esco 
dynamotor. The filament supply is derived 
from an 8 volt storage battery. Due to the 
fact that there is no electricity at our ranch, 
the dynamotor is driven from 12 volts of 
storage cells. Others more fortunate can use 
ordinary 1 10 volt or 220 volt AC supply to run 
the motor of the motor-generator. 

THE ANTENNA SYSTEM 

THE writer firmly believes that most of 
the remarkable success achieved with this 
particular lo-watt Hartley set is due to the 
antenna system used. It was adopted after 
several months of experimenting. And having 
a goodly number of acres upon which to string 
wire, the size was not evolved from any lack 
of space, but rather from the indicated needs 
of the transmitter. 

The masts are too wood poles, about 55' high 
above ground, and spaced 90" apart. The 




FIG. 8 



How to Build a Good Low-Power Transmitter 



259 




FIG. 9 

one at the lead-in end of the antenna is 20' 
from the wall of the transmitter room. 

The horizontal portion of the antenna consists 
of four wires in the form of a cage, spaced by 
light wooden spreaders to a diameter of 3'. 
The cage is 60' long, and tapers to a point at 
each end. The tapering sections are 6' each. 
The antenna is supported by two wires extend- 
ing from each mast and broken by two 10" elec- 
trose insulators at each end. The reason for 
spacing the masts on a go' center, while the an- 
tenna is only 60' long, will be presently seen. 

The lead-in is also a cage of four wires, 
spaced 16" apart at the top, and tapering to 
a junction at the grounding switch. The 
lead-in spreaders are of heavy gauge wire, 
soldered to the lead-in, and are 8' apart. 

The counterpoise is made of 8 No. 14 copper 
wires, directly un^er the antenna, and spaced 
on 2' centers. A 14' piece of 2 x 8 is bolted to 
the outside of each mast, eight feet above the 
ground, and the counterpoise wires stretched 
between insulators fastened to these cross 
members. The counterpoise wires are con- 
nected electrically at the "off" end by a wire 
soldered to each one, bridging them together. 
At the lead-in end they are continued past 
the mast, and drawn together in a long 18' 
taper, making the total length of the counter- 
poise 1 08'. All eight wires are then twisted 
into a cable and brought 12' to the grounding 



switch, mounted on the outside wall of the 
transmitting room. It is three feet through 
the wall and up to the binding posts, from the 
grounding switches of antenna and counter- 
poise. The connecting wires are led through 
1 8" porcelain wall-bushings, protecting the 
wires for a space of 5" on each side of the wall. 

TUNING THE SET 

THE Hartley circuit is very critical in 
adjustment, and a maximum radiation at 
the several wavelengths can only be secured 
by experimenting with the clip contacts on the 
oscillation transformer. But just as a starting 
point, the writer will give a couple of adjust- 
ments as used at ylT-yXAF-KFJR. For 
195 meter CW work the key circuit is connected 
at the first turn, the counterpoise at the fourth, 
the negative filament at the seventh, the plate 
at the sixteenth, and the antenna at the 
seventeenth turn. The counterpoise-series 
condenser is set at 65 on the dial. By adjust- 
ing this condenser, wavelengths from 220 to 
145 may be secured. 

When used for broadcasting on 258 meters, 
the following adjustments are made. The 
series condenser is cut out; the grid or "key" 
circuit is left at the first turn; the counterpoise 
is connected to the seventh; the filament to the 
tenth; the plate to the twenty-third; and the 
antenna to the twenty-fifth turn. Other ad- 



BATTERIES--.. 




FIG. IO 



260 



Radio Broadcast 



justments will be found by the experimenter. 
But in every instance the indicated plate 
current should be kept below 100 mills for CW 
and at about 60 mills for telephone. The set 
will only radiate from i to i .4 amperes on CW 
and about 1.25 on telephone. But forget 
the radiation and watch the DX! 

The transmitter built by the writer and his 
son, has been in use for the last six months 
both as broadcasting station KFJR and ama- 
teur station ylT. As ylT, the set has been 
reported as heard in all districts of the country, 
twice by WNP, once by Mr. W. G. Rose of 46 
Trewince Road, London, England and also by 
Australian 3BQ, Mr. Maxwell Howden, Mel- 
bourne, Australia. With it, stations on both 
coasts have been worked, as have a host of others 
as far south as New Mexico. The consistent 
range for CW seems to be something more than 
1,500 miles under average winter conditions. 

LIST OF PARTS REQUIRED 

i Weston Thermo-ammeter 0-1.5 
i Weston DC Voltmeter o-io v. 



1 Jewell Milliammeter. 0-300 

2 RCA PR-535 Rheostats 

2 Branston R-6y Series-Parallel Switches 

4 inch double-pole double-throw knife Switch 

43 Plate Dayton Condenser 

44 Plate Duntley Vernier Condenser 
Premier Open Circuit Jacks 
Premier Closed Circuit Jack 

5oL Giblin-Remler Coil 

3 RCA UC-IOI4 Faradon Condensers 
2 RCA Tube Sockets 

i RCA UL-ioo8 Oscillation Transformer 

1 RCA UP-4I4 Microphone Transformer 

2 RCA UP-iyig Grid Leaks 

1 RCA i Meg. Leak 

4 RCA UC-49O Condensers 

2 RCA UV-2O2 Radiotrons 
6 Eby "Commander" Posts 

500 Volt Esco Generator (Dynamotor or Motor- 
Generator) 

5 Ibs. No. 30 Enameled Wire 
5 Ibs. Silicon Steel (Sheet) 

30' No. 14 Copper Wire, hard drawn 

30' Spaghetti. 

i Mahoganite Panel 12" x 20" x \" 

Hard Wood Base, Maple Strips, Screws, etc. 




THE FINISHED TRANSMITTER INSTALLED 

At Mr. Dixon's Montana ranch. By following the instructions in the accom- 
panying article, the reader can easily duplicate for himself this transmittei 




THE PIT 

Center of the world's grain trading. Here daily meet the traders whose transactions regulate the wheat prices of the na- 
tion. Through the cooperation of the Chicago Board of Trade and their radio station WDAP. all interested farmers in 
the vast wheat belt can daily listen to the prices and stock exchange information directly from the Pit 

Linking the Farmer with His Market 



How the Chicago Board of Trade Brings the Wheat Pit to the Farm 
By ROBERT H. MOULTON 



M 



ORE than six centuries ago Roger 
Bacon was scoffed at when he 
said that machines for navi- 
gation were possible without 
rowers, so that huge ships guided 
by one man might be borne with great speed; 
that cars might be made so that they could be 
moved without a draught animal; and that even 
flying machines, a device with artificial wings in 
which a man might soar through the air like a 
bird, were possible. 

What would these scoffers have said if the 
prophetic Bacon had only gone a little further 
and added that it was possible, too, for a man 
situated alone in an isolated spot to hear the 
voice of the world by use of a seemingly simple 
device; for the farmer tilling his acres on some 



remote prairie to snatch from the air a voice 
which would tell him the exact value of his 
produce in the world market at almost any 
hour of the day! 

WHAT IS HAPPENING 

AND this is precisely what is happening 
under the latest method of broadcasting, 
grain price quotations by radio telephone. A 
special survey recently made by the Govern- 
ment through county agricultural agents lo- 
cated in the different states, disclosed that in 
2,850 agricultural counties alone there is an 
average of 51 sets of radio per county, or a 
total of more than 145,000 sets in such counties. 
One of the most important radio stations 
now broadcasting market news and price 



262 



Radio Broadcast 



quotations is station 
WDAP, located on the 
top of the Drake Hotel 
and owned by the Chi- 
cago Board of Trade. 
The Board of Trade, 
indeed, was a pioneer 
in this work. This ra- 
dio magic had scarcely 
astounded the country 
when the grain trade 
leaders of Chicago rec- 
ognized its great value 
in distributing market 
information. They 
were quick to see that 
it would perform the 
invaluable feat of link- 
ing the country grain 
merchant with his 
market, and of keep- 
ing the farmer in close 
and constant touch 
with all factors which 
might affect the price 
of his produce. 

Accordingly, the 
Board of Trade early 
in the spring of 1922 
started its radio serv- 
ice, the market quota- 
tions being broadcast 
from station KYW of 
Chicago. In spite of 
the somewhat limited 
facilities and the new- 
ness of the venture its success was instantaneous. 
Letters and telegrams began pouring in, com- 
mending the service, and urging that it be con- 
tinued and extended. They came not only from 
indiv i dua 1 
farmers, but 
also from 
country ele- 
vators, ship- 
pers, banks, 
business 
houses and 
even educa- 
tional institu- 
tions that use 
the Board of 
Trade price 
quotations in 
class work. 



More Than Music From the Air 

One farmer in Ohio tells how he got a tip from the 
ether which yielded him $19.60. The tip was an 
unexpected rise in the live stock market, coming at a 
time when the farmer was preparing to sell a ship- 
ment of hogs to a local buyer. As a result of listen- 
ing-in he got in touch with the city market and 
$19.60 was his profit over the local buyer's quota- 
tions, after all shipping expenses were paid. 

Since then the farmer has made good use of radio. 
This is how he links the ether with his agricultural 
business: 

"When I installed my outfit in 1922, I determined 
to get something from the air besides music. I 
could receive reports from two large city markets, 
and a number of smaller ones; and to keep tab on 
these I bought a ledger. 

"At the top of each blank page I wrote down the 
city where the market was located and the names of 
the principal dealers therein, with their addresses. 
This book is kept on the table where the radio is 
located, and when 1 have something to market I 
get in touch with one of these cities, and write down 
quotations as I receive them. Then I 'tune in' for 
another city, and get their prices. Afterward, I 
go over these reports and compare them. 

"It is a simple matter then to estimate distance, 
shipping cost, and so forth and from this I can select 
my market. 

" Dealers in these cities are aware of my method, 
and I have made arrangements with them by letter 
to accommodate my shipments at any time. This 
not only applies to live stock, but to poultry, eggs, 
and butter. The latter articles are shipped by parcel 
post the morning after the quotations are received. 

" I have a wide range of markets to select from, 
where formerly I was compelled to depend upon a 
local buyer's quotations, or those in the newspaper, 
which were always two days late. 

"And the radio offers another advantage: By get- 
ting weather reports and crop conditions from 
different parts of the country, 1 can guess pretty 
accurately the trend of the market." News item in 
the New York Times. 




THE 



RECORD 

On this blackboard are posted the price changes as they occur. 
The radio operator gets his information here and sends it broadcast 



Definite advices 
soon showed that in 
Illinois alone nearly 
five hundred towns 
and villages were us- 
ing the quotations. 
Hundreds of farmers 
not in easy communi- 
cation with towns ob- 
tained small radio re- 
ceiving sets for home 
use. Reports from 
other states told a 
story of similar inter- 
est in the new service. 

HOW WDAP WAS 

BOUGHT 

TT WAS then that 
1 the B0ard of Trade 
determined upon a 
permanent, continu- 
ous broadcasting 
service. This led the 
association t pur- 
chase outright the big 
radio sending station 
WDAP. The power 
of this station at that 
time is indicated by 
the fact that on many 
occasions messages 
were repeatedly sent 
to steamers2,5Oomiles 
at sea off the Atlantic 
Coast, the messages 

being confirmed back by radio telegraph. Yet 
even this failed to satisfy the requirements of 
the Chicago exchange, with the result that the 
station was recently remodeled (July, 1923), 

making it one 
of the most 
complete of 
any in Amer- 
ica. 

To-day a 
lone dealer in 
any isolated 
district of the 
grain belt may 
tune-in with 
his small re- 
ceiving set 
and in a mo- 
ment be as 



Linking the Farmer with His Market 



263 



fully informed of the value of his grains as are 
the best posted merchants in the great central 
markets. Not only does he receive the quota- 
tions then being established by trades on the ex- 
change floor of the Board of Trade, but he like- 
wise receives the most intimate and important 
current market news. This news includes re- 
ceipts, visible supply, weather, conditions in 
foreign lands that might have a bearing on the 
value of American grain, and such other items 
of interest that help to make up the daily 
budget of infor- 
mation covering 
grain production 
and distribution. 
Fortified with this 
knowledge, the 
dealer, once 
largely in the dark, 
is prepared to be 
judicious about 
shipping his grain 
to market. 

"RAPID FIRE IN- 
FORMATION " 

A> FOR the 
farmer, listen 
to this letter from 
a tiller of the soil: 
"We live on a farm 
loo miles north- 
west of St. Louis, 
Missouri, and 15 
miles away from 
any railway sta- 
tion. Six months 
out of twelve we 

consider a trip to the railroad station a 1 6-hour 
job get up at 4 A. M. and get home around 8 
P.M. ourselves and teams worn to a ragged edge. 
We seldom got prices on wheat, corn, oats, and 
hogs until they were a week or more old, and so 
we just had to guess at when it might be a good 
time to ship our stuff to market. But now, with 
our little receiving set we get rapid fire informa- 
tion, and we always listen-in to reports before we 
start to market with our grain, and quite often 
the neighbors gather here to hear the markets." 
This homely letter suggests how one radio 
receiving outfit can benefit hundreds of farmers, 
congregating around the crossroads' store or 
other assembling points. Country banks, mills, 
and elevators have come to see the importance 
of having radio receiving outfits for the benefit 



THE PIT 

Who observe and record 



of the farmers, the market news being posted on 
bulletin boards where all who come may read. 

BEHIND THE SCENES IN CHICAGO 

IT IS interesting to go behind the scenes and 
see the manner in which the price quotations 

on grain, which reach the farmer by radio, 

originate. 

The daily sessions on the Chicago Board of 

Trade open at 9:30 in the morning and close at 

1:15, except on Saturday when the closing hour 

is noon. A few 
minutes before 
the opening, the 
spacious trading 
floor of the ex- 
change is astir. 
Traders are chang- 
ing from street 
coats to light jack- 
ets before entering 
the pits. Messen- 
gers are scurrying 
about, hands 
crammed with or- 
der blanks. From 
one corner of the 
room comes the 
steady click of 
countless tele- 
graph instru- 
ments. 

Suddenly, on 
the stroke of nine- 
thirty, a giant 
REPORTERS gong sounds. It 

all price changes in the pit is like the crack 

of a pistol at the 

start of a hundred yard dash. The pits are gal- 
vanized int life. Overnight orders to buy and 
sell grain and provisions are rapidly executed 
Buyers, representing the consumer, seek the low- 
est price. Sellers, representing the producer, 
seek the highest price. The figure at which 
these two forces meet represents world values. 
In one corner of the room is a huge black- 
board on which a man posts the opening prices 
within a second or two after they are registered 
n the pits. Seated in a glass cage and over- 
looking this blackboard is a radio announcer. 
He is in direct communication with radio 
station WDAP a-top of the Drake Hotel a 
mile away, and without an instant's delay is 
calling off the quotations to an army of dealers 
and farmers scattered throughout the grain belt. 




264 



Radio Broadcast 




his grain, however, that the farmer 
looks upon the radio news service 
maintained by the Board of Trade as 
a real blessing. It has always been a 
difficult matter for him to choose what 
he considers the most opportune time 
to ship his grain. Usually he is not 
in a position to study the daily price 
changes, and certainly not on the very 
day the changes are taking place. 

25OO PRICE QUOTATIONS FREE DAILY 






B 



THE W D A P ANNOUNCER 
Sending out the market quotations from his desk in the Board of Trade 



One of these farmers, for example, is Jim 
Pepper, far out on a lonely ranch in South 
Dakota. He wishes to learn whether the time 
is opportune to ship his wheat. He steps to 
his little radio receiving set, tunes in to the 
36o-meter wavelength, and what he hears runs 
about as follows : 

"This is station W-D-A-P Drake Hotel, 
Chicago Board of Trade Station W-D- 
A-P. . . . Opening prices on the Chicago 
Board of Trade. . . . May wheat. . . . 
One, twelve and a quarter. . . . July 
wheat. . . . One ten and three-eighths. . . ." 
So it goes. 

The opening prices of the three active futures 
in each grain, wheat, corn, 
oats, rye, barley, and in pork, 
lard and ribs are given. This 
information is followed by 
important market comment 
such as receipts and ship- 
ments; estimated car lots; 
Liverpool cables; estimated 
cattle, hogs, and sheep; live 
stock receipts and prices; 
weather forecast; receipts 
of hogs; cash grain prices, 
and so on. Additional mar- 
ket information, including 
closing futures quotations, 
is sent out at the close of 
each session. In the evening, 
beginning at seven o'clock, 
musical programs are given 
which entertain city folks 
as well as farmers. 

It is in connection with 



farmer is closely linked with his 
market. He may have, hot off the 
wires, the latest news that is likely to 
affect prices of grain and provisions; 
he may have the freshest statistical in- 
formation from Government and other crop re- 
porting sources; he may have price quotations 
almost while they are being posted. Indeed, all 
the facilities of the vast crop-reporting system of 
the Chicago Board of Trade, which have ever 
been one of the marvels of modern commerce, 
are now placed at the disposal of the farmer 
free of charge. 

An average of twenty-five hundred quo- 
tations, or price changes, on wheat, corn, oats, 
rye, barley, pork, lard, and ribs are issued from 
the Chicago exchange on every business day. 
A majority of this average daily number con- 
cerns wheat. Since Chicago is the largest 
and most important grain exchange in the 




"BUY AND SELL" 

Orders come in and are signalled to the traders in the pits. Prices at which the 
transactions are made are noted by the pit reporter and flashed by Morse code to 
the blackboard operator who posts them. The WDAP announcer then reads 
these quotations into the microphone 



Linking the Farmer with His Market 



265 



world, these quotations are of vital interest to 
everyone concerned with the production of 
distribution of these commodities and to per- 
sons in scores of related industries. 

Even before radio broadcasting grew to be 
generally used, every one of these quotations 
was available in all cities and towns throughout 
America, where wire facilities are maintained, 
within a few seconds after the price is registered 
in one of the pits. This almost instantaneous 
service is possible by means of the complex 
and ingenious "ticker" system, which is more 
or less of a mystery even to members of the 
grain trade. 

Let us follow a single quotation. Com- 
mission houses that are members of the Board 
of Trade have their representatives in the 
trading pits. We will suppose that a com- 
mission house receives an order from a miller 
or cereal manufacturer to buy ten thousand 
bushels of May wheat at, say, a dollar and ten 
cents a bushel. This order is immediately 
telephoned to the firm's telephone operator on 
the trading floor. He rushes a memorandum 
to the firm's representative in the pit and the 
latter immediately executes the order. 

The price at which the transaction was made 
is noted by an official reporter on a raised plat- 
form over the pit. This is possible because all 
trades, both as to quantity and price, are 
carried out through the medium of the sign 
language, or system of signalling with the 
fingers, employed by the traders, and which is 
an open book to one familiar with it. The pit 
reporter writes the price on a slip of paper and 
flips it to a man at his side, who stamps the 
paper with a chronograph, a machine which 
registers the time of the trade down to the 
second. A third man on the "telegraph 
bridge" receives the slip, stamps it with 
another chronograph, and hands it to a telegra- 
pher who operates a master key. 

A flash by Morse code places the quotation 
in the offices of the ticker company. There it 
is put on the keyboard of the ticker, and is 
immediately clattering along to hundreds of 
offices. Meantime, a master circuit on the 
telegraph bridge has sent the quotation through 



six automatic repeaters which work with light- 
ning speed and to which is attached a network 
of wires covering the United States and Canada. 

Such rapidity has been attained that the 
average time consumed from the moment the 
trade is made in the pit until the price appears 
on the ticker is only three and three-fifths 
seconds. 

In the past the Board of Trade has spent 
fortunes in an effort to give the farmer first 
hand information on the ever-shifting world 
supply and demand. With the radio, the 
effectiveness of this service is vastly increased. 
The complete ownership and operation of 
station WDAP brings the association no 
financial return. But it is working to the 
mutual advantage of the members and their 
world-wide clientele. It is a step forward in 
the endeavor of the exchange to acquaint the 
public in the grain business and out with the 
operations of the world's greatest grain ex- 
change and the largest international enterprise 
located in the Middle West. 

According to Henry A. Rumsey of the Board 
of Trade radio committee, plans are now under 
way to send out from station WDAP complete 
educational courses, ten minute talks, covering 
various subjects in agriculture. The first 
courses will probably deal with grains, begin- 
ning with the preparation of the soil, then the 
planting, harvesting, marketing, and on down 
the line through the trade channels until it 
reaches the consumer. 

"Our primary object," Mr. Rumsey said, 
"Is to send out unbiased market reports. In 
broadcasting reports we do not give out any- 
thing that would tend to express opinion of 
influential persons. We try to give only fair, 
unbiased information gathered from official 
sources and a correct report of the value of the 
products. From this information we hope the 
farmer will be able to determine the value of 
his products and know when he is being offered 
a fair price. Our interest in the radio is from a 
strictly service point of view." The president 
and secretary are the only members of the 
Board of Trade who are allowed to speak from 
station WDAP. 



f\NE of the best-known old timers in wireless is John R. Irwin the operator at Siasconsett 
^^ in /pop who received the CQD distress signal from Jack Binns on the "Republic" and so 
took a most important part in one of the fir"st radio rescues at sea. Mr. Irwin was the first air wire- 
less operator on Waller bellman's dirigible "America" which set out in /pop to cross the Atlantic 
and failed. But Mr. Irwin and his pioneer wireless outfit saved that brave crew of six from 
drowning. He teUs the story himself in RADIO BROADCAST for August. 



Results of the "How Far" Contest 

Who Won the Six Prizes in the Two Contests and How Far They Heard 

DECI DING one of RADIO BROADCAST'S distance receiving contests is only a shade less difficult 
than the biblical difficulty that wise King Solomon had in deciding the ownership of the 
infant. The decision in both the divisions of the contest that for home built sets and that 
for bought or ready made receivers was not altogether based on the total mileage, but on the en- 
tire character of the contest entry, of which the requested photographs, description, and diagram, 
as well as the log, were a part. 

Entries there were of all sorts, some of which admittedly did not comply with the terms of the 
contest but were sent in as a bit of sport most of these were fine. For instance, there was R. 
Bartholomew, of Garrochales, Porto Rico, who won our last "How Far Have You Heard?" contest, 
who sent us in a carefully typewritten log of stations he heard on his prize set, the De Forest D-io 
which he received last May. And from Apia, Samoa, came a long-delayed letter from Mr. Quincy 
F. Roberts, the American vice-consul, with his entry, which contained some phenomenal "longest 
single jumps." And, it must be confessed, there were some entrants whose riotous imagination led 
to ridiculous entries on their logs. Those few got scant attention. 

THE WINNERS 

READY MADE RECEIVERS 

FIRST PRIZE Mrs. Eva L. Rhodes PRIZE WoN 

Utica, N. Y. Mu-Rad, type MA-I5 receiver 

SECOND PRIZE O. B. Evans, Fada Neutrodyne " 160" 

Mount Pleasant, Michigan 

THIRD PRIZE Alex. B. Nicol, Sonochorde Loudspeaker 

Bogota, New Jersey 

HOME BUILT RECEIVERS 

FIRST PRIZE Dr. W. C. Wolverton, Complete set of parts for Haynes super-hetero- 

Linton, North Dakota dyne 

SECOND PRIZE M. F. Winne, Complete set of parts for a " Knock-Out 3-Tube 

Webster Groves, Missouri Set" described in February RADIO BROADCAST 

THIRD PRIZE Kenneth Danielson, Complete set of parts for " Knock-Out 3-Tube 

Thermopolis, Wyoming. Reflex Set" with Sodion detector tube. 

A FEW REMARKS 

T N OUR distance receiving contests, the first prize has been won by a woman. It was accomplished 
L by Mrs. Eva L. Rhodes of Utica, New York, who logged a total distance of 85,5 10 miles, with best 
single jump of 2,480 miles, and a total of 140 stations heard. The second prize winner in the first 
group, Mr.O. B. Evans, of Mt. Pleasant, Michigan logged 84,620 miles, his best single jump was 2,345 
miles, and he heard a total of 129 stations. Mr. Alex. B. Nicol, of Bogota, New Jersey was the third 
prize winner. He heard 93 stations totalling 68,520 miles with best single jump of 3,149 miles. 

ABOUT THE HOME BUILT SETS 

E of the best and most complete logs of reception we have ever seen came in with the winning 
contest entry of Dr. W. C. Wolverton, of Linton, North Dakota who received 148 stations 
during the contest period totalling a distance of 121,535 miles with the longest single jump 3,000 
miles. The second prize winner, Mr. M. F. Winne, of Webster Groves, Missouri heard 175 stations 
with a total distance of 1 15,088 miles, and his best single jump was 2,070 miles. Kenneth Daniel- 
son of Thermopolis, Wyoming, won the third prize in the home built sets division with 149 stations 
totalling a distance of 135,190 miles. His best distance jump was 2,1 80 miles. 

WHAT THE CONTEST PROVES 

IN AN early number, we shall publish a list of the entrants in the contest, the distance they suc- 
* ceeded in attaining, and the type of receiver they employed. These facts, taken together with the 
location of the contest entrant should provide some very interesting reading for those who arecurious 
to know what a given type of receiver with ordinary intelligent handling will do in a given locality. 
Many receivers were ruled out of this contest because they were radiating. RADIO BROADCAST is 
firmly opposed to radiating receivers. 1 f radio receiving is to be made pleasantly for everyone, radiat- 
ing receivers cannot continue in use. And in this connection, it is interesting to note how generally 
interference from radiating receivers was recorded on the logs of the contestants. So, every receiver 
whose performance was considered in this contest was a non-radiating receiver. See what they did! 



How the Vacuum Tube Works 

WHAT MAKES THE WHEELS GO 'ROUND: V 
BY WALTER VAN B. ROBERTS 



The central feature of most radio receivers and indeed of modern radio transmitters 
as well is the vacuum tube. It cannot, therefore receive too much attention. "How the 
Vacuum Tube Works" is the fifth article in Mr. Roberts' series which began in March. Each 
article is a unit in itself and those who did not start reading with the first article will have 
no difficulty in starting now. THE EDITOR. 



A QUALITATIVE idea of the process of 
detection can be got from Fig. 21. A 
simple but complete receiving set is 
shown, along with the grid potential- 
plate current characteristic of the 
tube for the particular plate battery voltage 
used. A three-volt C battery is assumed, and 
the dot on the characteristic at minus three is 
called the "operating point" because it is about 
this point that fluctuations occur. When radio 
waves of the frequency for which the antenna is 
tuned are arriving, they cause current of the 
same frequency to flow in the antenna circuit, 
of which the coil is a portion. These currents 
flowing through the reactance of the coil pro- 
duce alternating potential differences between 
the ends of the coil and hence fluctuations of 
the grid's potential relative to the filament. 
From the way the characteristic curve bends, it 
is easy to see that if the grid potential moves 
one volt to the right the plate current will in- 
crease more than it would decrease if the grid 
potential moved one volt to the left. Thus if 
the grid potential is fluctuating between the 
values 2 and 4 (at any frequency) the aver- 
age value of plate current will be greater than 
if the grid potential were fixed at 3. Further- 
more, if the grid potential alternates between 
- i and 5 the effect is still more pronounced. 
As a result of this we may say that the average 
value of plate current is increased 
by the presence of high-frequency 
current in the antenna, and the 
amount of increase is greater the 
greater the current in the antenna. 
Hence the average current through 
the receivers varies in the same way 
as the voice current used at the 
transmitting station to modulate "^ 



the radio waves, so that the voice is repro- 
duced by the receivers. A "soft" or gas-filled 
tube detects in the same way, but is more sensi- 
tive owing to peculiarities in its characteristic. 
However, to get the advantage of these 
"kinks," a critical adjustment of filament 
current and plate voltage is required, for which 
reason the "soft" detector is not recommended 
for general use. 

46. THE "SQUARE LAW" FOR DETECTION 

THIS same result may be reached in a more 
quantitative fashion by using the previ- 
ously mentioned equation for plate current, 
i p = K (B + ^ X grid potential) 2 . For sup- 
pose the voltage input to the grid is a sin pt, 
where a is the amplitude of the alternation of 
grid potential. Then i p = K [B + [i (C + a 
sin pt)] 2 = K [(B + 11 C) + ^ a sin pt] 2 = K (B 
+ [i C) 2 which is direct current of constant 
strength + 2 K y. (B + [x C) a sin pt which is 
radio-frequency current, for above audible 
frequency + K [i 2 a 2 sin 2 pt which reduces to 
radio-frequency current of twice the wave 
frequency plus a new direct current of strength 
\ K ix 2 a 2 . This last term is the addition 
to the normal direct current through the 
receivers, and is greater the greater the ampli- 
tude of the incoming waves, as was concluded 
previously. This analysis however shows ex- 




268 



Radio Broadcast 



acily how the average current through the 
phones varies with the amplitude of the in- 
coming waves; it varies as the square of the 
amplitude. The fact that the detected current 
varies as the square, and not merely directly as 
the amplitude, is very important, for reasons 
that will be taken up in connection with radio- 
frequency amplification later on. 

47. DISTORTION 

TO OBTAIN a complete analysis of de- 
modulation, however, we must substitute 
in the equation for plate current the whole 
sum of frequencies that compose the modu- 



MMM 




FIG. 22 



lated waves. Let the voltage input due to the 
carrier be a sin pt, and that due to the upper 
side band S b; sin (p + qO t and that due to the 

lower side band Cj sin (p qj) t where ~^ may 

be any frequency from say 30 up to 5000, and 
\)\ and Cj are the amplitudes. The S indicates 
in a shorthand way that we are considering 
the sum of all such terms present. The 
equation for plate current then becomes i p = K 
[(B+/ C)+(a sin pt + S b ; sin (p+qO t+S Cj 
sin (p qj)t)] 2 . The expansion of this into a sum 
of simple terms is quite straightforward but 
rather tedious. Neglecting steady direct cur- 
rents and currents of frequencies above audibi- 
lity, we get as a result of the expansion not only 
the terms proportional to 2 abjcos q ; t + 2 aq 
cos qjt either of which represents the frequencies 
present in the original voice, but also a term pro- 
portional to 2 2 bjCjCos (qi+qj)t which represents 
frequencies not necessarily present in the origi- 
nal voice, but of small magnitude compared to 
the desired terms if the coefficients b; and q are 
small compared to a. If these coefficients are 
very small the quality of the received voice is 
good but the incoming waves are so little 
modulated that the signals are weak. If the 
coefficients are large (that is, the waves are 



strongly modulated) then the signals are strong 
but the quality is impaired by the extraneous 
frequencies becoming noticeable. A compro- 
mise must be struck at the transmitting station 
between overmodulation and consequent dis- 
tortion and undermodulation and loss of signal 
strength. 

48. DETECTION AND HOW THE GRID CON- 
DENSER AND LEAK OPERATE 

A DIFFERENT method for detection than 
/V the above is the one commonly used as it 
is somewhat more sensitive. The difference 
as shown in Fig. 22 is the removal of the C or 
"grid bias" battery and the substitution of a 
small capacity condenser shunted by a very 
high resistance. The operation of the circuit 
may be roughly outlined as follows: in the 
absence of incoming waves the potential of the 
grid is the same as that of the filament. In- 
coming waves cause the grid to become alter- 
nately more positive and more negative than 
the filament. While the grid is more negative 
nothing happens, but while it is more positive 
it attracts electrons. These electrons cannot 
get off the grid once they are on it (the grid is 
not hot like the filament) except via the high 
resistance which is called the grid leak. If for 




FIG. 23 



the moment we suppose there is no grid leak 
provided, we can see that after a very few 
waves have come in the electrons drawn to the 
grid will charge it to a steady negative potential 
equal to the maximum instantaneous potential 
of the top of the coil in the antenna circuit. 
This steady negative potential causes a reduc- 
tion in the plate current. Even if the waves 
cease coming in or their amplitude is dimin- 
ished, the grid retains its negative charge since 
there is no way for the electrons to get off it. 
So we put in a very high icsistance path by 
which they may slowly (compared to the wave 




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Radio Broadcast 



frequency) escape so that if the amplitude of 
the incoming waves slowly (i. e., at voice fre- 
quency) diminishes, electrons will leak off until 
the grid potential drops to the new maximum 
value of potential at the upper end of the coil. 
Thus the potential of the grid more or less 
faithfully follows variations in the amplitude 
of the incoming waves and hence causes the 
plate current to do the same, which is exactly 
what is required for the purpose of demodula- 
tion. In this system, the greater the strength 



of incoming waves the less the plate current, 
exactly the reverse of the other system. The 
connections shown in Fig. 23 are often 
recommended. In this case the grid be- 
ing connected to the positive end of the fila- 
ment draws electrons all the time, but simi- 
larly to the type of demodulation (first 
described, the grid current increases more 
during the positive half wave than it decreases 
during the negative half, so that the result is 
the same. 



Supplemental List of Broadcasting Stations in the United States 

LICENSED FROM APRIL 19 TO MAY 16 INCLUSIVE 



CALL 




(KILO- 


WAVE- 


POWER 


LETTERS 


LOCATION 


CYCLES) 


LENGTH 


(WATTS) 


KFPX 


Pine Bluff, Ark 


1240 


242 


100 


KFPY 


Spokane, Wash 


1060 


28 3 


loo 


KFQB 


Fort Worth, Texas 


1180 


254 


loo 


KFQC 


Taft, Calif 


1320 


227 


100 


WCBW 


Macon, Ga 


... 1330 


226 


10 


WCBX 


Newark, N. J 


1290 


233 


too 


WCBY 


Buck Hill Falls, Pa 


1 1 20 


268 


10 


WCBZ 


Chicago Heights, 111 


1210 


248 


50 


WDBA 


Columbus, Ga 


I27O 


236 


20 


WDBB 


Taunton, Mass 


I3IO 


229 


10 


WDBD 


Martinsburg, W. Va 


I 1 2O 


268 


5 


WDBE 


Atlanta, Ga 


I 190 


252 


10 


WDBH 


Worcester, Mass. 


I 1 2O 


268 


100 


WDBI 


New Orleans, La. 


I24O 


242 


10 


WDBJ 


Roanoke, Va 


I3IO 


229 


20 


WDBK 


Cleveland, Ohio 


I2IO 


248 


IOO 


WDBL 


Stevens Point, Wis 


I080 


278 


500 


WDBN 


Bangor. Maine 


I igo 


252 


5 


WGN 


Chicago, 111 


8lO 


370 


1000 


WRBC 


Valparaiso, Ind 


IO8O 


278 


500 



LIST OF BROADCASTING STATIONS DELETED MARCH i TO APRIL 30 



KDYW 


Phoenix, Ariz. WE AS 










Washington, D. C. 


KDZF .... 


... Los Angeles, Calif. WIAR . . 










Paducah, Ky. 


KFCM .... 


. . . Richmond, Calif. WJAF . . 










Muncie, Ind. 


KFDL .... 


. . . Denver, Colo. WJAZ . . 










Chicago, III. 


KFEJ .... 


. . . Tacoma, Wash. WJH 










Washington, D. C. 


KFHS .... 


. . . Lihue, Hawaii WKAY . . 










Gainesville, Ga. 


KFJW .... 


. . . Towanda, Kans. WMAW . . 










. Wahpeton, N. Dak. 


KFOB .... 


Minneapolis, Minn. WMAZ 










Macon, Ga. 


KNV .... 


... Los Angeles, Calif. WPAH . . 










Waupaca, Wis. 


KSS .... 


. . . Long Beach, Calif. WPAQ . . 










Frostburg, Md. 


KUS .... 


. . . Los Angeles, Calif. WQAD . . 










. Waterbury, Conn. 


KXD .... 


. . . Modesto, Calif. WQAV . . 










Greenville, S. C. 


WABK .... 


. . . Worcester, Mass. WRAD . . 










Marion, Kans. 


WBAD .... 


Minneapolis, Minn. WRAZ 










Newark, N. J. 


WBBI .... 


Indianapolis, Ind. WSAH 










Chicago, 111. 


WCAY ....... 


. Milwaukee, Wis. WSAL 










Brookville, Ind. 



TOTALS 

Number of U. S. broadcasting stations 584 

Number of Canadian broadcasting stations 44 

Number of Cuban broadcasting stations ,,,... 34 



RADIO BROADCAST ADVERTISER 




$5.00 



ULTRAFORMERS 
Types A and B 

New improved long wave fre- 
quency transformers, especially 
designed by R. E. Lacault, 
A. M.I.R.E., Consulting Radio 
Engineer of this company ami 
inventor of the Ultrndyne. 
The Ultraformer (Type B) 
may be successfully employed 
in any circuit where long 
wave radio frequency trans- 
fonrers are essential. 
To protect the public, Mr. 
Lacault's personal monogram 
seal (R. E. L. ) is placed on 
all genuine Ultraformers. UI- 
traformers are guaranteed so 
long as the seal remains un- 
broken. 





Send for 32 page illustrated 
book, giving latest authentic 
instructions on drilling, wir- 
ing, assembling, and tuning 
6 and 8 tube Ultradyne re- 
ceivers. 



A dominating feature 

An Ultradyne Receiver operating in New York 
City can easily tune out the powerful broadcasting 
of WOR Newark, N. J., 405 meters and bring in 
WDAR Philadelphia- 395 meters; PWX Havana, 
Cuba 400 meters; WDAF Kansas City- 411 
meters. Regardless of close similarity in wave 
length, the Ultradyne selects any station brings 
in broadcasting clearly, distinctly, faithfully. 
The "Modulation System" of radio reproduction is 
used exclusively in the Ultradyne. It is the latest 
achievement of R. E. Lacault, A.M.I.R.E., Consult- 
ing Radio Engineer of this company and formerly 
Radio Research Engineer with the French Signal 
Corps Research Laboratories. 

The "Modulation System" increases the sensitive- 
ness of the Ultradyne over that of any known re- 
ceiver. Weakest signals are made to operate the 
loud speaker. A superior instrument to even the 
famous Super-Heterodyne. 

Ultradyne performance is the envy of the radio industry. 



Write for descriptive circular 



SUPER-HETERODYNE 



PHENIX RADIO CORPORATION 
5-7 Beekman St. New York 




"The Standard of Comparison' 



Tested and approved by RADIO BROADCAST 




QUERIES ANSWERED 



PLEASE EXPLAIN IN DETAIL THE NEUTRALIZATION OF THE ROBERTS CIRCUIT 
WHAT Is THE ADVANTAGE OF USING A COUNTERPOISE WITH MY RECEIVER? . 



/. B. D., Galveston, Texas. 
G. B. N., Cleveland, O. 



PROPERLY NEUTRALIZING THE ROBERTS CIRCUIT 

HERE is a further explanation of the system employed 
by Mr. Roberts to overcome oscillation in the radio- 
frequency amplifier. Detailed instructions for their 
construction appears in the articles by Mr. Roberts in the 
April and May issues of RADIO BROADCAST. The winding 
N is used to prevent regeneration. The coils N and P are 
wound on the same form and as close together as is phys- 
ically possible. 

Assuming that the set has been made, proceed as follows: 
Turn the tickler coil up so that it is closely coupled to the 
secondary coil in the detector circuit. Using the variable 
condenser shunted across the secondary, tune-in the whistle 
of a transmitting station and then fix this adjustment. 
Then slowly rotate the first variable condenser, first one 
way, then the other, listening to the changes in intensity, 
not pitch, of the squeal. If it so happens that the squeal 



>- 
^ 

i/o 



U-J 

ZD 
CO 




DIAL SETTING 

FIG. I 



first increases gradually then quickly slumps down, then 
quickly increases and quickly decreases, it is evident that 
the proper balance has not been obtained. Try sliding the 
neutralizing tube in the opposite direction of its original 
position for only a short distance and repeat the variation 
of squeal intensity. When the neutralizing tube has been 
adjusted so that at a certain point on the dial of the first 
condenser there is a comparatively quiet spot a few degrees 
either side of this point but gradually and equally increas- 
ing, and decreasing as the dial is rotated further away from 
this point, the proper location for the neutralizer has been 
found. This explanation will be better understood by re- 
ferring to Fig. i . "X" shows the silent point extending from 
B to C while A-B indicates a gradual increase in intensity 
and C-D indicates a gradual decrease in squeal intensity. 

A COUNTERPOISE FOR THE RECEIVER 

SHARPNESS of tuning without any sacrifice of volume 
has been the goal of many constructors who "build 
their own." The need forsharper tuning has manifested 
itself more in the larger cities having several broadcasting 
stations, and when using certain types of receivers, es- 
pecially the reflex set. 

One of several ways to obtain this sharpness of tuning is 
by the use of a counterpoise instead of the usual grounding 
arrangement. A counterpoise is very similar to an an- 
tenna, is composed of one or a number of wires and is in- 
sulated in the same manner as an antenna. Usually it is 
placed beneath the antenna and elevated from the ground 
by several feet, to suit the taste of the individual 
constructor. If there is danger of tripping persons by hav- 
ing it quite near the ground, then it will have to be elevated 
at least "head high." 

For use in the city, where such a system most applies, the 
counterpoise may be erected in the cellar or basement of 
the house, when the other space is not available. If this is 
the case, suspend the wire or wires from the ceiling far 
enough so that there is no chance for it to touch other ob- 
jects. 

The important point to remember is to have the counter- 
poise insulated up to the receiver. A general idea of coun- 
terpoise construction may be had from Mr. Dixon's article 
in this issue. 



RADIO BROADCAST ADVERT1SKH 



The Choice of Radio Experts" 




For the 
Super- 
heterodyne 

and 

Long Wave 
Reception 



Shielded 
Electro- 
statically 

and 

Electro- 
magnetic ally 



TYPE 271 



Medium Frequency Transformer 

AMPLIFICATION of wavelengths around 10,000 meters falls be- 
-t~V tween the ranges of radio and audio frequencies. It, therefore, 
requires a transformer materially different in design from radio or 
audio frequency transformers. The type 271 M. F. Transformer is 
specially designed to meet the specific requirements of medium 
frequency amplification. For use in the Superheterodyne and in long 
wave reception it is unequalled. 

It is shielded electrostatically and electromagnetically. 

Very compact and rugged. An instrument of high electrical 
efficiency. 

Trice, $5.00 
GENERAL RADIO COMPANY 

Manufacturers of 

Electrical and Radio Laboratory Apparatus 
CAMBRIDGE, MASS. 



Write TO-DAY for Descriptive Bulletin 918B 



' """": -_ '.:. : i : ;. : . : . :: .v.:... : ^ 

GENERAL RADIO C9 

Cambridge, Mass. 


liENERAL KAU1U W 

x^^V 
V^ 

.kCaiiibridge.Mass.^ 

^^^ 


\. 



Tested and approved by RADIO BROADCAST 




THOROPHONE LOUD SPEAKER 

The new Thorophone is built on the solenoid 
principle, with a constant air gap which prevents 
varying impedance in the receiving set when the 
speaker Is being used. It has a power amplifying 
unit, and the horn is of thorite. This composi- 
tion is cellular and it will not resonate with any 
sound wave. It 
is a very good 
speaker. Made 
by W inkier- _ 

M C " Kl^H^RuB NA-ALD SUPER DE LUXE DIAL 

Chicago^n" BJ Like the other Na-ald dials, the Super De 

Price $45 oo Luxe is manufactured from black bakelite. 

It is made in the 3!" size with the gradua- 
tions clearly marked in white. Made by 
Alden Mfg. Co., Springfield, Mass. 





THE CHASLYN BALL BATTERY 

TESTING SET 

Consisting of a Ball Battery Tester, a Bat- 
tery Depth Gauge, and a Battery Water 
Filler. A complete and efficient equip- 
ment for learning the condition of your 
storage battery. Made by the Chaslyn 
Co., 3845 Ravenswood Ave., Chicago, 111. 
Price $1.00 






TUFGLAS BATTERY TRAY 
A practical and satisfactory means of 
insuringyour rugs and carpets against 
damage from the acid electrolyte. 
Made by Russell B. Cressman, 200 
Fifth Ave., New York. Price $1.50 

OPERADIO RECEIVER 

In this carrying case the manufac- 
turers combine a six-tube receiver, 
batteries, loud speaker and loop an- 
tenna very effectively. The loop is 
built inside the top of the case, which 
is shown open in this cut. Made by 
Operadio Corp., Chicagr, III. Price 
complete $190 



BRUNO ULTRA VARIO CONDENSER 
A well designed condenser in both electrical and mechanical 
details. Its construction makes its use possible as two sep- 
arate .00025 mfd. condensers, or in series to produce a 
capacity of .000125 mfd. Its regular maximum capacity is 
.0005 mfd. Made by Bruno Radio Corp., 300 Water St., 
New York City 



SUPERSPEAKER 

A loud speaker which has earned its 
right to rank with the best speakers 
now obtainable. The base unit has 
an adjustment which allows setting 
for the most suitable volume. Made 
by the Jewett Radio & Phonograph 
Co., 5680 i2th St., Detroit, Mich. 
Price $29.85 




RADIO BROADCAST ADVERTISER 




Transformers and Variable Condensers 



FADA 

Audio Frequency 

Transformer 
No. 171-A, $6.00 




FADA 

Variable Condensers 

No. 142-A (15 

plates .0003 mfd) 

$3.00 

No. 144-A (23 

plates .0005 mfd) 

$3.50 



More volume finer tuning 

POOR condensers absorb radio power 
that cuts down volume. Poor con- 
densers add resistance that broad- 
ens tuning. You can sharpen your 
tuning, increase selectivity and get 
greater volume with the new FADA 
"low-loss" variable condensers. Use 
them. The low power factor and low 
equivalent series resistance prove 
their superiority. FADA "low-loss" 
condensers are more efficient than 
many so-called precision condensers 
and have a capacity ratio of 40 to 1 
as compared with 30 to 1 usually en- 
countered. Two sizes No. 142-A 



Performs as well as it looks 

The new FADA Audio Frequency 
Transformer is encased in bakelite 
with nickeled binding posts and 
soldering lugs. It looks "quality" all 
over. And it performs up to its ap- 
pearance. It has a high average 
amplification over all the broadcast- 
ing wave-bands and reproduces voice 
and music with a volume and tonal 
fidelity that is surprising. A wonder- 
ful addition to the audio frequency 
stages of Neutrpdyne receivers and 
equally efficient in other types. This 
new transformer, No. 171-A, is made 
possible by correct FADA engineer- 
ing principles and by uniform produc- 
tionmethods. Ratio 4 to 1. Price$6.00. 



(15-plate .0003 mfd) at $3.00 and No. 
144-A (23-plate .0005 mfd) at $3.50. 

Ask your dealer for FADA Transformers and Variable Condenser* 

F. A. D. ANDREA, INC., 1581 Jerome Avenue, New York 



P 4B*-* T*M nA BEG, m. PAT.Orf. ^~ 



Tested and approved by RADIO BROADCAST 




RADIO receivers sometimes temporarily im- 
pair "domestic tranquility" as well as 
bring enjoyment to their owners. Henry J. 
Peck, in the second of his covers for this magazine 
has rather well caught one of the moods of a radio 
owner, we think. We can promise the reader 
another cover by this artist in an early num- 
ber. 

WILLIAM H. GARY, JR., has left France, 
where he has been for some months, to 
begin a trip around the world. We expect to 
hear from him what the Indo-Chinese are doing 
with radio and how broadcasting is coming along 
with the Sumatrans. As a matter of fact, this 
interesting writer gave us to understand in a 
recent letter that he was really exploring to see 
how "far-flung" the ends of the earth really 
were. 

EDWIN H. ARMSTRONG has not been 
back so. long in New York from his honey- 
moon which he spent last winter in Florida. 
Mr. Armstrong, with his quiet manner and quite 
fascinating drawl, is often seen around the busy 
campus of Columbia University in or near the 
radio laboratories. 

JULIAN KAY, whose second article in the 
"What's in a Name?" series appears this 
month, has left New York temporarily to do some 
research work with vacuum tubes in Boston, but 
he promises this will not prevent him from send- 
ing us the other ar- 
ticles in the series, 
the next of which 
will appear soon. 

ZEH BOUCK, 
the editor of 
"In the R-B Lab" 
and pleasantly fre- 
quent contributor to 
RADIO BROADCAST, 
is one of the prize 
winners in the recent 
radio drama contest 
held by W G Y. 

Bouck in his eager effort to pen a stirring drama, 
called it Bootleg. The snapshot shows that 
"learned Theban" in a queer Bermudan carriage 
in front of Tom Moore's House Tavern at Ber- 
muda, where two of the scenes of his radio play 
are laid. He claims to be leaving the place, 
but we dunno. 




ZEH BOUCK 



JAMES C. YOUNG is a well-known New York 
newspaper man whose frequent contribu- 
tions to the Sunday New York Times are familiar 
to readers of that excellent newspaper. Like 
all newspaper men, and Mr. Young is indeed a 
good one, he has a wide acquaintance. The other 
day he was out on a revenue cutter and. . . 
Anyhow, he has written an extraordinarily inter- 
esting story about radio on the "rum fleet" off 
New York, which will appear in this magazine soon. 

WENDELL BUCK is engaged in radio 
advertising. Not very long ago he left 
New York for the uncertainties of Chicago to 
take up his duties for a large New York retail 

radio store whose 
Chicago branch has 
just been opened. 




A s 



SHLEY C. 
DIXON is a 
native of Chicago 
and attended school 
and the University of 
Chicago there. He 
moved to Montana 

A. C. JR. AND A. C. DIXON in IQII and has been 

there ever since on 

his ranch at Stevensville. "My former hobbies 
were hunting and amateur photography", he 
writes, "but now I think my present and future 
hobby is radio. " His son A. C. Dixon, Jr. stands 
beside him in the photograph. Dixon, Sr. has an 
amateur radio operator's license, while his son, 
at 15 holds a commercial operator's ticket. 

NO TRUE fisherman hides his prowess under 
even a secretive conversational bushel, and 
here we see Robert H. Moulton with part of a 12! 
pound fish caught 
in Black Lake, Wis- 
consin. Mr.jMoulton 
is a graduate of Co- 
lumbia University, 
spent some years on a 
Chicago newspaper, 
and is now in that 
city as a free-lance 
writer on a wide va- 
riety of subjects. He 
took the photographs 
which illustrate his 
article "Linking the 
Farmer With His 
Market" himself. R. H. MOULTON 




RADIO BROADCAST ADVKH! u- 



, 

Radiola Regenoflex, with 
Radiola Loudspeaker, and 4 
Radiotrons WD-1 1; with space 
for batteries inside; (complete 
except batteries and antenna) 
206 




All the jazz of the big orches- 
tras in faraway big towns 
comes through clearly for 
dancing. The fine music is 
true, sweet toned, undistort- 
ed. The sports news rings 
out with all the thrill of 
bleachers or ringside. The 
Regenoflex is a leader among 
the new Radiolas that are 
making this a great radio 
summer ' 



This symbol 
of quality 




is your 
protection 



Send for the free booklet that 
describes every Rudiola. 



RADIO CORPORATION OF AMERICA 

Dept. 37 ( Address office nearestyouj 
Please send me your free Radio Booklet. 

Nam 



Street Address 



City 



R.F.D. 



State 



REG. U. S PAT OFF 



a Radiola 

on the Front Porch 

A Radiola Regenoflex on the front porch 
and that porch can be way up in the 
mountains, or off at the seashore but it's 
not too far away to be in on the fun. 

The improvements in its mechanism offer 
greater sensitivity and greater selectivity; 
clearer tone; and complete simplicity. 
Where quality of reception counts as much 
as distance, the Regenoflex is the receiver 
for this summer's fun! 

K(r fheres a Radiola /or every purse" 

Radio Corporation of America * 

Sales Offices 

233 Broadway 10 So. LaSalle Street 433 California Street 

New York Chicago, 111. San. Francisco, Cal. 

Radiola 



Tested and approved by RADIO BROADCAST 




Roger B. Whitman, Country Life. 
A PROPER SETTING FOR A SUPER-HETERODYNE 

One of the eight-tube super-heterodynes, built in the RADIO BROADCAST laboratory, operating on a loop beside the North 
pool in the gardens of the Doubleday, Page & Company plant, where RADIO BROADCAST is published. A radio receiver 

can be ornamental, and decorative as well as useful 



RADIO 
BROADCAST 




Vol. 5, No. 4 



A Knock-Out Short- Wave Receiver 

Describing How to Build this Sensitive and Selective, Non-Radiat- 
ing Receiver for Very Short Waves, Employing the Roberts Circuit 



BY ZEH BOUCK 



FOREWARNED is forearmed, and the 
writer maliciously announces that 
resonance will be treated in this 
article in terms of kilocycles rather 
than wavelengths. This is at all 
times the more efficient and logical considera- 
tion. Eventually, wavelength will be con- 
sidered only secondarily and no better start 
can be made in thinking in kilocycles, than 
in a discussion of short 
waves, which we al- 
ready refer to famil- 
iarly as higher fre- 
quencies. 

As a final magnani- 
mous concession to the 
vanquished, we state 
that the wave range to 
be considered in this 
article is from about 
1360 kilocycles 220 
meters to a shade 
over 3000 kilocycles, 
a bit under 100 meters. 
1500 kilocycles is the 
frequency of 200 me- 
ters, and 2000 kilo- 
cycles the vibratory 
rate of 1 50 meters. If 
the reader insists on 
being inefficient, and 



A Good Thing and a Small Package 

The possibilities of very short-wave trans- 
mission and reception have been appreciated 
for several years, but RADIO BROADCAST has 
consistently declined to publish data on a 
high-frequency receiver while the single-circuit 
oscillator offered the only simple and efficient 
receiving system. Mr. Bouck tells you why, 
and our forbearance is amply repaid in the 
receiver he has designed. 

Here is a receiver that will appeal most 
powerfully to the serious experimenter the 
enthusiast interested in the short-wave trans- 
mission of KDKA at 3000 kilocycles (100 
meters) and WGY at 2800 kilocycles (107 
meters) and to the relay amateur who will 
find this set designed with an especial, and 
perhaps instinctive regard to his particular 
problems by one of his own kind. THE 
EDITOR. 



must know the wavelengths of the intermediate 
frequencies, he will be under the necessity of 
dividing 300,000 by the number of kilocycles. 

THE REQUIREMENTS OF A SHORT-WAVE SET 

THE higher radio frequencies are less stable, 
more difficult to tune and control than the 

lower conventional broadcasting frequencies. 

They therefore impose more exacting require- 
ments on the possible 
methods of reception. 
Various losses, which 
are comparatively neg- 
ligible on the higher 
waves, become more 
pronounced and have 
a more detrimental ef- 
fect on transmission 
and reception on ama- 
teur and sub-amateur 
waves. While it is 
probable that the mag- 
nitude of these losses 
has been exaggerated, 
they nevertheless ex- 
ist, and every possible 
precaution should be 
taken to reduce 
them. Large size 
wires, with a prac- 
tical minimum of 



280 



Radio Broadcast 



insulation, should be employed in wiring and 
winding the inductances. The size of wire, of 
course, determines the actual resistances in 
the circuits, and the elimination of unnecessary 
insulation does away with a dielectric, which if 
employed consistently and needlessly, may add 
materially to capacity losses. 

CAPACITY EFFECTS 

AS THE frequency is raised the effect of 
capacity upon resonance becomes much 
more critical and marked. For instance, an 
addition of ten micro-microfarads (.00001 mfd.) 
to a circuit oscillating at 3000 kilocycles, at 
which frequency KDKA transmits short-wave 
telephony, will decrease the frequency by 
about 400 kilocycles. The same capacity 
added to a receiver or transmitter oscillating at 
750 kilocycles (approximately the frequency of 
WJ Y, WOR and PWX) will cause a decrease of 
only 69 kilocycles. 



KDKA PITTSBURGH, RA, RECEIVED AT NEWTON 
CENTRE, MASS., MAY 17, .1924 ON HARMONIC 
AT 9000 AND FUNDAMENTAL OF 3000 K'CYCLES 



9000 KILOCYCLES 



I 



3000 
KILO 



f W, 



1 ( 



. 9060 
h KILOCYCLES 




FIG. I 

Interesting graphs made by the signals themselves at the laboratory of 
Dr. Greenleaf Whittier Pickard. These tell why the short-wave re- 
ceiver must not radiate 



It is quite obvious that body capacity effects 
present somewhat of a genuine problem on these 
high frequencies, especially when it is con- 
sidered that most of the receiving carried on in 
this region is beat-note reception of continuous 
wave telegraph signals. In a poorly designed 
short-wave receiver, a slight motion of the 
hand in the vicinity of the tuning controls will 
be sufficient to whistle a station clean across 
the audible scale and out. In the receiver to 
be described, body capacity has been reduced to 
a satisfactory minimum, by mounting the os- 
cillating coils at right angles to and away from 
the panel, by connecting the stationary conden- 
ser plates to the grids, and by using metal dials 
insulated from both the ground and the instru- 
ments they control. (Grounded shielding 
would immediately introduce losses. The in- 
dividual control dials act partly as shields, and 
at the same time reduce the capacitative coup- 
ling between the body and the instruments by 
functioning as the common plate of 
two condensers connected in series). 
The increased susceptibility of 
receivers of this type to capacity 
variations also makes vernier con- 
trol a necessity. However, as a 
built-in vernier generally adds to the 
condenser losses, non- vernier conden- 
sers are recommended with vernier 
dials. The Accuratune dial, a true 
vernier and possessing the desirable 
insulated metal scale, was used by 
the author. 

THERE MUST BE NO RADIATION 

THE most important considera- 
tion of all is the necessity for 
a non-radiating receiver. This abso- 
lutely essential condition has proved 
a serious problem, for most of the 
communication carried on in the 
higher frequencies postulates a re- 
generative and oscillating receiver. 
It is an easy matter to build a single- 
circuit regenerator to operate in the 
region of megacycles but the radia- 
tion from such a receiver places it 
absolutely and irreconcilably beyond 
the pale. We are all painfully fa- 
miliar with the havoc worked by 
such sets on the broadcasting fre- 
quencies. It is the writing on the 
wall, with an added and sinister em- 
phasis, for radiation on amateur and 



A Knock-Out Short-Wave Receiver 



281 



ul+ '41+ 




"C"- 6V. 



DEI AMP. 

"B" 

FIG. 2 
The short-wave circuit. The C battery should be varied as one of the amplifier stabilizing adjustments. 



sub-amateur waves possesses a remarkable 
carrying power that adds many miles to the 
radius of the interference area. 

HOW THE HIGHER FREQUENCIES CARRY 

THE possibilities of these very high fre- 
quencies are uncanny. Using a small re- 
generator with a ten inch antenna (needless to 
say, indoor), the writer has copied foreign low 
power stations operating in the neighborhood 
of 3000 kilocycles. Distant amateur stations 
have also been received on high harmonic 
frequencies which could represent only a small 
fraction of the already low power radiated on 
the fundamental. Dr. Greenleaf Whittier 
Pickard has had similar results in a room at the 
Commodore Hotel in New York City. Due to 
the freak element in these frequencies, distant 
broadcasting stations are often received much 
more consistently and loudly on their harmonics. 
KYW, at Chicago, is often recorded at Newton 
Centre, Massachusetts, on the 8th harmonic at 
greater intensity than on the fundamental. 
Doctor Pickard, in his study of short and long 
period variations, has made these extremely 
short waves photograph themselves; and has 
no unusual difficulty in obtaining a beautiful 
graph of the variations in WBBR's sixth 
harmonic at 7500 kilocycles. Fig. i shows a 
most remarkable photograph, which the author 



is reproducing with the kind permission of 
Doctor Pickard. This masterpiece of labora- 
tory finesse shows the simultaneous variations 
in strength of KDKA's fundamental at 3000 
kilocycles (already far above the region of con- 
ventional broadcasting) and its third harmonic 
at 9000 kilocycles. 

HOW TO PREVENT RADIATION? 

WHILE it was quite obvious that radiation 
must be practically eliminated, the man- 
ner of overcoming it was less apparent. A 
blocking stage of radio-frequency amplification 
will immediately suggest itself to the experi- 
enced reader, as it did to the writer. However, 
this would necessitate a plate coil, and as the 
tendency to feed back through the capacity of 
the tube increases with the frequency, the 
amplifying bulb would prove a far more power- 
ful oscillator than the detector unless efficient 
means were taken to stabilize the circuit. 

THE ROBERTS CIRCUIT ON SHORT WAVES 

IT WAS upon the suggestion of the editor of 
RADIO BROADCAST that the writer began ex- 
perimenting in his own amateur station, radio 
2P1, with the possibilities of the Roberts re- 
ceiver especially designed for short waves. As 
our readers who have followed Mr. Roberts 's 
articles, on his "Two-Tube Knock-out Re- 



282 



Radio Broadcast 




FIG. 3 

Front view of the finished receiver. The dial arrangement is for left hand operation, 
the usual order of the tuning controls being reversed. The tickler is on the left. 



ceiver" appreciate, this circuit employs one 
stage of tuned R. F. with capacity neutraliza- 
tion, bulb detection with regeneration, and one 
step of reflexed audio amplification. It was a 
happy thought of the editor and has developed 
into the receiver shown in the last five illustra- 
tions of this article, and which we have found 
to be in all ways the most desirable short-wave 
set we have ever operated. And we have 
played with many of them. 

The circuit is shown in Fig. 2, and most of our 
readers will recognize it as the standard Roberts 
hook-up with a slight variation in Ti . A semi- 
aperiodic primary has been substituted for the 
tapped coil which is quite unnecessary and 
actually detrimental in high-frequency recep- 
tion. 

All inductances, excepting the windings of 
the audio amplifying transformer, are spider- 
webs. The writer found it most convenient to 
obtain the standard Roberts broadcast wave 



coils, made by the Eugene Turney Laboratories 
and rewind them for the special short-wave set. 
If the reader desires to make his own forms,they 
should have an odd number, say seventeen 
winding spokes, with a first-turn-diameter of 
two and a half inches. Pasteboard is the pre- 
ferred material. 

The primary of Ti is wound with six turns of 
No. 18 wire. S, in both Ti and T2, has 25 
turns (see General Instructions) with the inside 
terminals running to the grids. Pi and P2 
in T2, is the combined primary and neutralizing 
winding. It is made as follows: Two No. 22 
wires, from individual spools, are wound simul- 
taneously for eight and a half turns. This re- 
sults in two parallel coils. The beginning of 
one coil is connected to the end of the other, 
giving a common terminal which leads to the 
output jack. The remaining two connections 
run to the plate and to the neutralizing con- 
denser C3 (it is immaterial which runs to which). 



r- 



DRILLED TO SIZE DETERMINED 
BY DIRECTIONS FOR MOUNTING 
VERNIER D1MS..V-... 



HOLES 



-c- 



-- 



nutco 7 
, I*'.' , V , 

-e-o-e o-O-o * 

' 1 r ' ' ' 




4 AND REAMED 
FOR JACK. 



21". 



FIG. 4 
I he panel layout. The design is such as especially to suit the operating convenience of the majority of amateur stations 



A Knock-Out Short-Wave Receiver 



283 



The tickler coil consists of eleven turns of No. 
1 8 wire. 

With the exception of the secondaries, all 
coils are wound over one, under one, in refer- 
ence to the winding spokes. The secondaries, 
which are wound with No. 18 wire, are woven 
over three and under three. 

Capacities Ci and C2 are .00025 m W. low- 
loss, low minimum capacity variable conden- 
sers with the stationary plates connected to the 
grids. Duplex condensers were used by the 
writer. C4 and C$ are fixed capacities, respec- 
tively .001 mfd. and .002 mfd. (see General 
Instructions). 

C4 is the grid condenser and leak, having re- 
spective values of .0005 mfd. and 250,000 ohms 
(refer to General Instructions). The neutraliz- 
ing condenser, C3, is made by winding No. 
24 wire over two inches of spaghetti tubing and 
slipping this on a convenient length of bus-bar 
wire left projecting from the grid terminal of the 
amplifying socket. The capacity of this con- 
denser is varied by slipping the insulated tube 
farther on or off the bus-bar. 

T3 is an Amertran audio-frequency trans- 
former, connected as indicated by the marked 
terminals. 

The output is plugged into a Carter open cir- 
cuit filament control jack. 



The reader need not confine himself to the 
specific parts used by the author. He may use 
the products of other manufacturers if he is 
certain that the substitute is of equal quality. 
But he must insist on this, for a single piece of 
inferior apparatus may impair the successful 
operation of a short-wave set. 

THE PANEL 

A BAKELITE panel, seven by twenty-one 
1~\ inches, was drilled according to the speci- 
fications in Fig. 3 and grained to a beautiful 
gray-black finish. The markers for the dial 
readings are scraped into the panel with the 
point of a dividers or scriber, and whitened with 
chalk or prepared paste. The simplicity of 
these three single lines is most pleasing, and 
harmonizes beautifully with the grained panel 
and the Accuratune dials. 

CONSTRUCTION 

THE various building details are clearly 
shown in the photographs, and adhere 
strictly to the theoretical implications con- 
tained in the earlier part of this article. Make 
all wiring as uncrowded and rigid as possible, 
using spaghetti sparingly and only where it. is 
a necessity or a genuine convenience. 
The writer has arranged the various controls 




FIG. 5 
Rear view. Spaghetti is used only where necessary, and on flexible lead* 



284 



Radio Broadcast 




FIG. 



The mountings for the Micadons and the combined grid leak-condenser mounting permit the clip- 
.ping in and out of different values. This is desirable in the preliminary adjustment of the receiver 



in an order the reverse of that usually employed, 
the antenna inductance and Ci begin on the 
right, following up to the tickler on the extreme 
left. This best suits the operating convenience 
at station 2PI, where the antenna switch and 
sending key are operated by the right hand 
and placed to the right of the receiving ap- 
paratus. The relay operator should consider 
these details, employ his own ingenuity, and 
vary the construction accordingly. 

GENERAL INSTRUCTIONS 

THE operation of the set is similar to that 
of the ordinary regenerative receiver. The 
three controls, Ci, C2, and tickler, are quite 
analogous respectively to primary, secondary, 
and regeneration on the old and comparatively 
inefficient receivers. 

Tubes 

Your favorite detector and R. F. amplify- 
ing combination will work successfully. As 
will be seen in the photographs, the author 
employs the UV-2OI-A type in the amplifying 
circuit, and a Western Electric J tube as de- 
tector. It should be mentioned that only the 
modern low capacity amplifying tubes, such as 
the UV-199, the UV-2OI-A and the correspond- 



ing Cunningham and Deforest tubes, can be 
used in a short-wave amplifier circuit. 

Wave Range 

Using twenty-five turn secondaries as 
recommended the set will probably cover the 
stipulated range bounded approximately by 
1400 kilocycles and 3000 kilocycles. The exact 
wave possibilities of the receiver are best de- 
termined by the use of a transmitting wave- 
meter, or a standard semi-short-wave receiver, 
such as the Grebe CR-3, on which the oscillat- 
ing frequencies are approximately known. 
The wavemeter or former receiving set should 
be made to oscillate at 1 500 kilocycles and the 
beat-note produced at a neighboring frequency 
on the new receiver. This will be quite high 
up on the condenser C2 scale. Now tune down 
for the second harmonic which will be found 
exactly on 3000 kilocycles. If difficulty is ex- 
perienced in attaining this higher frequency, 
wire is removed, turn by turn, from the second- 
ary of T2 until the harmonic beat-note is 
easily tuned with a few condenser degrees to 
spare. It is a simple matter to secure any 
desired high frequency by tuning for the second 
harmonic of a known lower frequency. 

Wire should also be removed from the se- 



A Knock-Out Short-Wave Receiver 



285 



condary of Ti, until condenser Ci tunes to 
resonance at about the same dial reading 
as C2. 

Coupling 

The coupling between P and S of Ti is close, 
the two coils being separated by about one- 
half inch. In the case of the writer, similarly 
close coupling between Pi and S in T2 has 
proved more efficient that the loose coupling 
recommended by Mr. Roberts on the higher 
frequencies. The tickler coupling will of 
course vary with the degree of regeneration 
desired. In receiving continuous wave signals, 
the coupling should be loosened to within a few 
degrees of where the oscillations stop. 

The Neutralising Capacity 

The primary adjustment of C^ is made to 
determine the setting at which the ampli- 
fying tube refuses to oscillate over the entire 
frequency range, a capacity that is seldom 
critical and which permits considerable leeway. 
A second and more exacting adjustment should 
be made during transmission of a near-by and 
powerful station to discover the point within 
the neutralized area where the incoming signal 
ceases to induce a howl. 

Final Adjustments 

In all cases it is desirable to experiment with 
the values of 4, C<j, the grid condenser and 
grid leak. To facilitate this, Daven mountings 
have been used by the author for clipping in 
these parts. Two condenser mountings are 



necessary for 4 and C$, and a combined 
condenser-leak mounting for CR. 04 affects 
the stabilization of the amplifying tube, while 
the correct values of C5, the grid condenser and 
resistance for individual tubes, regulate the 
action of the local regenerative and oscillating 
circuit. These last values should be adjusted 
until the detector circuit goes into and out of 
oscillation over the entire range, smoothly and 
without howling. 

Antenna 

A special antenna will seldom be required 
for the operation of the short-wave set. It is 
used by the author on his double cage, fifty- 
five-foot L transmitting antenna. 



EGARDLESS of the appeal to the experi- 
1 V menter, the transmitting amateur will 
find the receiver we have described particularly 
adapted to his own very exacting requirements. 
Passing over its great sensitivity and perfect 
wavelength range as being obvious and under- 
stood by the relay man, we desire to emphasize 
in closing the truly remarkable selectivity of 
this two-tube set. Key-click, excessive ripple, 
and other disturbances from near-by faulty 
transmitters are reduced to a most gratifying 
minimum. At 2PI little difficulty was ex- 
perienced in copying a DX station through a 
local 50 watt rectified A. C. C. W. transmitter 
located less than one thousand feet away, both 
stations oscillating within four kilocycles of 
each other. 



B-BATTERIES FROM YOUR LAMP SOCKET 

CONSTRUCTION details and complete diagrams of an arrangement which 
will permit the use of no-volt alternating current to supply the plate 
potential on any receiver up to an eight-tube super-heterodyne will be printed 
in an early number of this magazine. The building of the device is not difficult 
and it can be made for about $25. 



O ON RJJM 

How it Makes Life 

amid Help^ His 





CELY, mate? Why, this ship is so lone- 
some that a man would begin talking 
to 'imself if it wasn't for the radio." 
We were leaning over the rail of a 
rum runner, as dirty an old tramp as 
ever slipped out of London on a dark night. 
Just now she was swinging to forty fathoms of 
chain off the Long 
Island shore. With a 
rainy sky above and a 
gray sea below, heav- 
ing underneath our 
bow, it was a day to 
make one think of a 
stuffed chair and a 
cheery fire. But this 
particular rum runner 
call her Augusta 
had been standing up 
and down Rum Row 
four months and not 
a man aboard had 
stepped on dry land. 
Add two weeks for the 
first trip across, with 
perhaps another 
month off shore, and yet two weeks more to 
cross again. Then we get a new conception of 
what it means to be lonesome. 

"Nothing to do at all," said the big man in 
the blue sweater, standing at our elbow. And 
the gray eyes in his burned face looked forlorn. 



What? No Romance? 



The certainties of modern existence have 
not yet eliminated all the romance from life, 
as readers of this very interesting article by 
Mr. Young will agree. The author has had 
the very unusual experience of visiting the 
liquor smugglers in their own haunts, "some- 
where on the Atlantic" outside the 1 2-mile 
limit. Though the business of the hardened 
crews on these ships is supposedly continu- 
ously exciting because of the risk and danger 
involved, the men, it seems, are actually bored 
to death. And right there is where radio is 
helping to lift them out of themselves. You 
will enjoy reading what broadcasts do for the 
outcasts. THE EDITOR. 



"Once Hi was wrecked in the Hindian Ocean 
and lived a month on some bloomin' crabs, 
but that was an heasy berth alongside this one. 
We just lay 'ere, rotting our 'earts. It's no 
life for a sailor. What they need on these 
blarsted ships is dummies, not men." 

" Why don't you go ashore at night and stay 
a while. Surely there 
isn't much danger?" 

" Danger enough, 
mate; not that Hi 
mind, but the old man 
wouldn't stand for it. 
'E lost one hofficer 
that way. What do 



you suppose? The fel- 
low was a drunkard 
and couldn't stay 
sober ashore, even 
when 'e'd been on a 
rum ship three 
months. So this 
blighter gets 'imself 
locked up and they 
deports him as a halien 
who 'ad no right to be 

in your bloomin' country. And 'e couldn't tell 

where 'e came from. 

"No; the old man wouldn't let me go. And 

if Hi went the crew would want to go, too. 

The only thing we can do is listen to the radio 

and wait for the boats to come out. Hi'll never 



Radio on Rum Row 



287 



make another rum. cruise. Why, one fellow 
up for'rard started to knit 'imself a sweater, 
like 'e'd seen 'is mother do. It was 'orrible 
the way 'e swore over that sweater. And Hi 
says that a ship where sailors begin to knit is no 
bark for me to sail on." 

By way of consolation for the Augusta's first 
officer, we suggested reading as a cultural and 
diverting influence. 

" Read?" he repeated, and paused to sink his 
anchor teeth in a new square of London plug- 
cut; "why, mate, Hi 've read every book in the 
old man's 
locker, from 
one called 
Surgery at Sea 
to another 
well, you 
could never 
guess what Hi 
found in that 
locker." 

" Romeo 
and Juliet," 
we suggested, 
at a chance. 

"No, no, 
matey, some- 
thing worse. 
It was all 
about a man 
who 'ad some 
strange 
hideas. 'Ewas 
called a well, 
now, what did 
they call him? 
Oh , y es , 
Pilgrim. The 
book was Pilgrim's Pilgrim's " 

"Progress?" 

"Right-o, Pilgrim's Progress. Well, Pil- 
grim was an odd one, Hi will say. 'E stopped 
me from this reading you talk about. The 
only fun we ever 'ave is the radio." 

"So you like it, then?" 

The first officer's face broke into its first 
smile. 

" Hi surely do," he said, " and as for the men, 
we couldn't keep them aboard without it. 

RADIO GAMBLING A NEW THRILL 

WHY, every night, they are lined up to get 
their turn at the 'ead set. Do you know 
what 'appened on this bloomin' ship? They 




"WHAT'S YOUR ORDER, PLEASE?" 

There is more speed than ceremony involved when the bootleggers supply the 
small boats which come out from shore to lighten the load of the marine merchant. 
It is apparently as easy to hand a case over the side as it is for the milkman to 
come up your domestic back steps with his wire basket full of bottles (milk) 



started gamblin' in the fo'castle, stakin* their 
turns at the radio when money gave out. Hi 
found one little tike who 'adn't been able to 
listen-in for a week, 'aving lost all his chances. 
So I 'ad to stop that radio gamblin'. We'd 
'ave 'ad a mutiny some night when there was a 
big concert." 

"What do the men like best?" 
"Oh, anything; mostly the jokes and those 
songs about 'ome you Hamericans are always 
singin'. Do you know (and he laid a confi- 
dential hand on our arm) Hi 'ave an hidea that 

this lonesome 
job makes a 
man think 
about 'ome 
more than he 
would. Now, 
as for me, Hi 
'ave a good 
woman and a 
young one, 
too, back in 
Lunnon and 
sometimes at 
night Hi get 
to thin kin' 
about them 
mighty 'ard. 
You know, 
matey, we just 
drop our han- 
chor here and 
begin to rot. 
It puts a man 
in a blue funk, 
before long. 
And when 
these radio 



athe News 



singers of yours start to sing about little 'ouses 
with the bloomin' roses a-twining all over 
them, a man kind of wishes he 'ad one and 
didn't 'ave to go rum running." 

" Do you get many stations on your set?" 
"Oh, yes, most anywhere. You see, we 
'as to 'ave a 'igh-powered set; but of course 
you know I must not talk about that. We 'ave 
'card a lot of stations, dozens of them, I would 
say. 'Ere, lad, how many stations do you 
reach?" 

His hail brought over to us a young fellow of 
about twenty-five, the radio operator. He had 
a coat with brass buttons, a cap of naval cut, 
and looked like a man who had seen service. 
Despite the rough-and-tumble life on a rum 



288 



Radio Broadcast 



runner, he kept a straight back and a smart 
salute. 

"We can hear almost any station within 
fifteen hundred miles," he said. "Of course 
we get WJZ and WEAF every night, along 
with many other stations near by. I don't 
know what the men would do without our 
radio. All of the big rum ships carry sets now, 
partly for the men and partly well, you under- 
stand. Even the schooners are rigging up 
antennas. Before long the whole fleet will be 
equipped to receive long distances and many of 
the ships can send as 
well. Would you like to 
see our radio room? It's 
all right, isn't it, Mr. 
Jamieson?" 

"Oh, sure, lad, lead 
away." 

We went forward, 
past a bulwark of cases 
standing breast-high, 
which several of the 
crew were handing up 
from an open hatch for 
the night's trade. The 

Augusta had sailed with 50,000 cases of Scotch 
and brandy and still had about one-fifth of her 
cargo below decks. She was a 5,000 ton tramp 
steamer, and save for her dirt, not unlike any 
other tramp. But surely this was the dirtiest 
ship afloat. Jamieson had the bearing of a real 
sailor and a sailor of the pure breed will not 
tolerate dirt aboard his ship. So we wondered 
but just then the Captain appeared, and the 
dirty ship was explained. He had a bleary, 
rum-soaked face, a heavy, red jowl, with a 
fringe of gray hair beneath a sou'easter. His 
clothes matched his face and he bestowed a 
glance upon us that fell like a blow. 

Perhaps it should be said that us included the 
writer and another man. By a special dis- 
pensation obtained through this other man we 
had come aboard the Augusta about noon of a 
murky day. She was twelve miles off shore, 
maybe fifteen, and her Captain had said that 
he would do us the honor of permitting a visit. 

We recalled that excellent rule, never to 
speak in some places until you are first ad- 
dressed, and waited for the Captain to have 
his say. It was brief enough. He nodded, 
remarked that it was a "Rotten day," and 
went aft with his glasses to study the shore. 
Judging from the growing bulwark of cases, 
customers were expected. 




TYING UP ALONGSIDE A RUM SHIP 



IN THE HEART OF A RUM RUNNER 

THE radio man disappeared down a ladder 
and we followed after, right into the heart 
of a rum runner. And there, in a little corner 
of his own, he presided over a magic key and 
receiving set which kept the Augusta in com- 
munication with a large part of dry America. 
"What's in the air?" asked Jamieson, and the 
edge on his voice revealed the true radio lover, 
always expectant of something to stir the spirit. 
The radio man Edwards did a few tricks 
with his instruments 
and looked up. " Some- 
body speaking at a 
luncheon," he said, "all 
about foreign trade and 
America's part 

"Aw, blarst that 
stuff," exclaimed 
Jamieson, "why do 
they let 'em do it ! Try 
hanother station, will 
you, Eddie?" 

Eddie tried and 
presently connected. 

"Springfield, Mass., sending out a minister's 
address at some meeting there. Hello, what's 
that? Oh, he says the dry law must stand and 
prohibition is an accomplished fact. He wants 
the President 

"Stow it, stow it, Eddie," pleaded Jamieson, 
the barometer of his expectation dropping pain- 
fully. Can't you get us a song or two, lad?" 
It was evident that we had come at the 
wrong hour really to enjoy a rum runner's 
concert. While Eddie searched the ether for 
a song and we suspected the first officer 
of wanting a sentimental song there was 
opportunity to take stock of the radio room. 
Why it should be below decks instead of above 
was not apparent, except that the Augusta 
had been built long before radio was known and 
there was no provision for quarters. But 
seemingly this did not influence the ship set 
because Edwards said that he could reach 
practically any desired point in the Eastern or 
middle States. 

"No songs, Mr. Jamieson," he remarked, 
"but here is another speaker. Wait a minute; 
he is going to tell a joke." 

"Let me hear, please," cut in Jamieson, and 
deftly took the set. But in another minute 
he flung it away. 

" Your Hamerican jokes are worse than ours 



Radio on Rum Row 



289 



at 'ome," he said, "Hi 'card that one in the 
music 'alls when Hi was a boy." 

RUM SMUGGLING UP TO DATE 

WITH that, the first officer started up the 
ladder and we reached for the set, just 
in time to hear the laughter. Edwards oblig- 
ingly did his best to tune-in something worth 
while, but the only themes in the air were 
luncheon speeches and weather reports. 

"Maybe you can stay over to-night," 
suggested Edwards, "when the big stations 
go into action. There is a concert scheduled 
at WJZ, with an Italian prima donna on the 
bill. We have a fine set and you will get a 
treat." 

"We certainly would like to stay. How 
about the Captain?" 

" Well that's so, but it will not do any harm 
to ask." 

" How long have you been aboard this ship?" 

"Oh, 1 just signed on for this cruise, and 
it's my last one. I came for the money, forty 
pounds a month, but it's no fun lying here with 
nothing to do. Our radio is the only thing 
that cheers us." 

" Do you have a good deal of business to 
handle, too?" 

"Well, 1 am not supposed to discuss that, 
although your legal people must know about our 
radio trade. You see, the big dealers in New 
York often send us orders by wireless and we 
have the goods ready for their boats when they 
come alongside. That saves time and reduces 
the risk of being seen. It also enables the shore 
boats to pay for their goods on land, without 
running the chance of hi-jackers robbing them 





Pathe News 

TEN THOUSAND CASES 
Are stowed in the hold of this ship. Very few are empty 



FASTEST OF ALL THE LIQUOR RUNNERS 

Is the steam yacht Glasgow, whose trim lines and saucy 

bow indicate that she could run away from almost any 

of the liquor patrol vessels now in commission 

somewhere on the way out. A lot of money 
has been lost that way. Why, I remember one 
poor blighter , who came aboard without a 
cent; they took $10,000 from him less than a 
mile away." 

"Can't the government agents trace your 
radio connections ashore?" 

"That is a hard thing to do," answered 
Edwards. "Long Island and New Jersey are 
full of antennas. It would be almost impossible 
to find all of them. And we do not have to 
establish connections with such near-by stations. 
We can take an order from Chicago just as 
easy as from anywhere else," he wound up with 
a wink. 

"Of course those orders are in code?" 
" Oh, yes, everything we send or receive is in 
code. A thousand sets might receive an order 
without understanding it. Then we are al- 
ways interested in the weather reports. Your 
storm warnings give us a chance to prepare for 
a big blow. This spring we had weeks of bad 
weather when the boats could seldom come out. 
And we were blown all up and down the coast, 
sometimes dragging our anchor for miles, in 
order to stay close in shore. It got so bad 
several times we had to heave the mud-hook 
and stand out to sea. One schooner was lost 
altogether and several ships parted their anchor 
chains." 

"Well, your pay is good, any way." 

" Yes, the pay is what gets the crews. Fo'- 

castle hands are drawing twenty pounds a 

month, when they would be lucky to get six or 

seven on any other ship. Even then it is hard 



Radio Broadcast 



to sign men for more than one trip. I don't 
believe the big ships really could keep their 
men in hand without radio sets and free al- 
lowances of rum. Sailors are used to long 
voyages, but they dislike especially lying idle 
in one place. Occasionally the men get so 
anxious for something to do that a few of them 
land in one of the small rum boats and stay for 
several days. But since we lost an officer 

" Yes, the first officer explained that." 

"Well, the old man has shut down on shore 
leave for everybody and we are cooped up here 
like prisoners." 

" Do you have any trouble with the crew?" 

The radio man arose before he answered and 
looked up the ladder. Then he came back and 
said in a half whisper: 

"There is more than one hell ship in the 
fleet. Most of these skippers are hard cus- 
tomers. They wouldn't take such a command, 
with a chance of getting into trouble and losing 
their papers unless they got big pay. And the 
cargo owners have a difficult time chartering a 
ship with a captain worth while. Many of 
these ships are tubs that have been rusting in 
Liverpool docks for a long time. 

"As for crews well, some of the fellows are 
the devil's own. Others are not so bad, real 
seamen who sign for the pay. Once in a while 
there is trouble. Our skipper carries a gun 
night and day, especially as he is the man who 
handles the money. But Mr. Jamieson is 
worth any three men aboard with his bare 
hands. They don't talk back to him. 

"On one ship they had a mutiny not long ago 
over the allowance of rum. The men are 
mighty lonesome and the rum cheers them up. 
Then they want more and more until they really 
get ship blues and insist on going ashore. The 
captain in this case refused and they had a fight 
that lasted a half day. The officers didn't want 
to shoot, fearing they would have to begin 
killing in earnest if a pistol ever cracked. So 
they went for the men with marlin spikes and 
the men went for them. It was about a half 
dozen against twenty, but they stood off that 
crew and somehow kept them from the liquor 
until the captain got things in hand." 

"Why didn't the other ships send help?" 

EVERY MAN FOR HIMSELF ON THE RUM FLEET 

IT IS a case of every man for himself out here," 
said Edwards. "We were down near the 
Highlands when this row took place off Mon- 
tauk Point and I only heard the details second- 



hand. But other skippers would be afraid 
to interfere because their own men might start 
trouble. These fellows get hungry-eyed, watch- 
ing all the money come over the side, and I 
would not be surprised if they seized some of 
it." 

" Has that ever happened?" 

" They say two ships have been deserted off 
shore, officers and men splitting up the money 
aboard. But I don't know. You can hear 
almost anything out here. Still I wouldn't 
doubt it."^ 

"And you think the radio helps to keep crews 
in good humor?" 

"No question about it. Unless there are 
boats to be loaded we have men down here as 
long as there is anything to be heard. They are 
like a crowd of boys, eager for something funny. 
And they have a fancy for your songs, too. 
Opera is a little out of their range and speeches 
are not popular. We have heard so many pro- 
grams in the last four months that we almost 
know the regular performers as old friends. 
Some of them go from one station to another 
and others appear regularly at a single station. 
I have heard that most of them are unpaid. 
Why do they do it?" 

"Often they are stage people and need the 
publicity." 

"Well, they certainly get it. I know some 
of their voices so well that I never shall forget 
them. Usually we can hear splendidly and I 
suppose that, having nothing to do, we con- 
centrate on the radio more than people ashore. 

"Sailors have a lot of odd tricks. Men who 
stay on a ship for months are likely to become 
a bit queer. The captain's boy mess boy, 
you know has a record of all the songs and 
singers he has heard and the bands and selec- 
tions played since we first cast anchor off this 
coast. I don't know what he expects to do 
with that list, but he spends hours making addi- 
tions, checking it up and talking to himself 
about it. You should see some of the spelling 
whew!" 

" How many ships are there in the rum fleet?' 

"Anywhere from seventy-five to a hundred. 
Some of them only make one cruise and find 
that it doesn't pay, especially the tramps. 
A big vessel like this one can easily carry fifty or 
sixty thousand cases. Unless the owners have 
connections ashore which assure a ready sale, 
they lose money through insurance costs, pay 
for the crew and general upkeep. The 
schooners, with ten or fifteen thousand cases, 



Radio on Rum Row 



have less expense and sell out in time to make a 
fine profit. But a big steamship with fifty 
thousand cases, sold in small lots, must stay 
here for months to clear her hold. 

" That is the trouble with us. We brought 
too much, struck bad weather, and I guess our 
shore agents have failed us. Sometimes, when 
your bootleggers find out that we are heavy 
laden and anxious to sail they will not buy, but 
force us into a corner and then get the liquor 
for almost nothing. One ship sold 10,000 
cases at $10 each in order to get away. The 
steamships which make money are those 
operated by big companies that begin to unload 
the moment they arrive. Some of these sail 
inside of two weeks." 

"ALL VISITORS ASHORE" 

AHOY, radio room," called a voice down the 
ladder and we went outside to see Jamie- 
son above. "All 'ands ashore is the captain's 
order," he said. "You better get started, 
young fellow." 

"Now, that's too bad," remarked Edwards, 
" I'd hoped you could stay over and share our 
mess to-night. Then 1 would have showed you 
what we could do with our set." 

" Maybe the Captain 

" I'll ask him for you," said Edwards. 

But the moment we placed foot on deck it 
was apparent that that request would be out of 
order. The Captain was hustling his crew 
around and the cases were coming up faster. 



There looked to be at least a thousand on deck, 
bearing a well known name White Horse. 
Our boat awaited and the leader on this ex- 
pedition stood at a ship's ladder made of rope 
dangling over the side. He nodded and we 
stayed not on the order of going. 

"Next time, come late in the afternoon," 
whispered Edwards, just as we started over the 
side. " Then you can stay and hear a concert." 

We promised and shook hands. Even the 
Captain granted us a perfunctory salute. 
Evening already had fallen and the chill of a 
wet night laid hold of us. We took a last hasty 
look around and thought again of the snug 
radio room and the concert we were about to 
miss. Also there would be warm food when the 
ship's bell rang again, and other cheer to 
comfort the heart. 

Against all of these advantages, an open boat 
awaited just below our heels and the two men 
in her were saying for a third time, "Come, 
hurry up." 

So we hurried, but paused yet a moment to 
say our last farewell. 

" I am coming ashore soon. And I 'opes by 
that time to hunderstand better your bloomin' 
Yankee lingo," said Mr. Jamieson. "You may 
strike me pink, but 1 cawn't make out the 'alf 
of it, mate, and that's the truth. 'Eave away." 

The motor sputtered and we fell away from 
her side on the next wave, into the night, taking 
every 'eart on the rum runner with us an 
unseen cargo. 




WASH DAY ON THE RUM FLEET 

The S. S. Rusk, riding at anchor off Long Island. This is one of 
the ships Mr. Young boarded on his visit to the forbidden fleet 



The Way of the Transgressor 

What the Common Deceptions in Radio Advertising and Selling Are- 
How the Novice May Recognize Radio Misrepresentation or Dishonesty 

BY WILLIAM P. GREEN 

Associate Director, National Vigilance Committee, Associated Advertising Clubs of the World 



Radio dealers with more knowledge of what they are pleased to call "sales methods and 
sales push" than of the actualities of radio, commit many crimes of which they are perhaps, 
quite ignorant, by the exaggerated claims they make verbally and in their advertising. The 
radio innocents accept these irresponsible claims and then there is trouble. Mr. Green de- 
scribes a clever deception in the private sale of "factory built "receivers, "sold at a sacrifice." 
He is well qualified to write on this subject of deception in advertising, since it is his 
business as an official of the Associated Advertising Clubs of the World to trace fraudulent 
and deceptive advertising. THE EDITOR. 



DRIFTING through the classified 
advertisements of a daily news- 
paper in any one of a hundred 
cities in the United States, it 
would not be at all out of the 
bounds of possibility to find an advertisement 
similar to the one reproduced below. 



"FOR SALE AT A SACRIFICE Stand- 
ard make, three tube set; tubes, A and B 
batteries, two sets of ear-phones, and non- 
power loud speaker, all in excellent condition. 
Call after twelve, 1 542 Hudson Boulevard, 
Apartment 14." 



Since you are interested in the purchase of 
a radio set, you reach the apartment around 
the middle of the afternoon. It is the usual, 
attractively furnished home of a person in 
fairly good circumstances. A middle aged 
woman answers the bell, and when you inquire 
if the one who advertised the radio set is in, 
she bids you enter to be seated a moment 
while she calls him. You find several minutes 
on your hands to look around and, of course, 
you are attracted almost immediately by the 
radio set on a table in the corner. You step 
over, lift the cover and observe the interior. 
It seems to have the appearance of a well 
manufactured instrument. 

As you turn a dial, the door is opened and a 
middle aged man walks in. He introduces 
himself as the owner of the set and explains 
that because of business difficulties, he is 



under the necessity of leaving the city imme- 
diately and, consequently, has offered the set 
at a sacrifice. His statement that he has had 
the set and equipment only a few weeks seems 
to be borne out by their fresh appearance. On 
the whole, the outfit would seem to be a bar- 
gain and after some questioning you agree to 
take it, provided it works when you return in 
the evening at a time when local stations are 
broadcasting. The test in the evening proves 
satisfactory and by nine o'clock you are on your 
way home in an automobile with the set and 
accessories beside you. 

Now comes the next day and with it the sec- 
ond act of this radio drama within the apart- 
ment. The man to whom you talked yester- 
day enters the same room, carrying the same 
type of radio set. His wife follows with sev- 
eral boxes containing tubes and a couple of 
pairs of ear-phones over her arm, all looking 
so much like the accessories you purchased 
yesterday that you easily would have mistaken 
them for your own. Within fifteen minutes 
the set is hooked up, and the tubes are in 
place, with the ear-phones carelessly placed 
over the back of the chair as though the owner 
had left them there after listening the night 
before. 

The explanation of this situation is that in- 
stead of being under the necessity of leaving 
the city because of business difficulties, this 
man and his wife are in the business of selling 
radio sets and equipment, which they purchase 
from some fly-by-night manufacturer and sell 
to the public at a profit. They are following 



the practice which, for years, has been a 
menace in the furniture and music business. 
Among the trade they are known as "gip" 
residence dealers. No sooner do they sell a 
set and equipment to one person than a similar 
outfit is brought up from the cellar and put up 
in its place. The appeal of the sacrifice offer, 
with the added atmosphere of installation 
within their home, enables these people to do 
a substantial business. 

PUBLIC CONFIDENCE IS BEING UNDERMINED BY 
DECEPTION 

THIS is one example of abuses to be found 
in radio merchandising and advertising 
to-day. It is among the more extreme prac- 
tices of deception, and those which are to fol- 



Why Serial Numbers Are Used 

and 
Why We Remove Them 

Every neutrodyne set has a serial number 
either engraved on the panel or fastened inside 
the cabinet. By this means manufacturers 
have been able to keep track of every set 
leaving their factories, and where necessary, 
have traced sources of supply. In our efforts 
to protect the public from being overcharged 
and to protect the wholesaler who sells us from 
"getting in wrong," we have removed every 
serial number from every neutrodyne set in 
our stores. The result our source of supply 
is not cut off and the public benefits by our low 
prices. 



the effects of which will be felt even by the 
more reputable manufacturers and retailers. 

It is a well known axiom that a counterfeiter 
always copies something of value. When a 
new field opens up, and particularly one like 
radio, which has enjoyed a mushroom-like 
growth, the faker soon appears on the scene 
to capitalize the success of legitimate industry. 
The public suffers, the honest merchant is 
placed at a disadvantage, and the industry as 
a whole shows increasing evidences of decep- 
tions that undermine confidence. 

We have an excellent example in the manu- 
facture of tubes, for particularly in recent 
months has there been a marked increase in 
the number of tubes designated as "201 -A" 
by concerns which are appropriating an identi- 




ATTENTION!! 

Receivers bear a 
serial number engraved on the panel. 
If this serial -number is effaced the 
sets are considered defective and are 
not the latest improved instruments, 
guaranteed by us. Beware of purchas- 
ing apparatus from 
unreliable sourcest 

Look for the name and the serial number 
engraved In white letters on the panel. This 
Is the only way to identify a genuine 

factory built and factory guaranteed 



wi^~""iBB^' ^jutfl 3&Jf* 



BOTH SIDES 

These two pieces of advertising copy, one, that of a retailer, and the other that of 
a manufacturer, appearing on the same page of the same newspaper, show the bitter 
fight being waged between the manufacturers of sets and the cut price stores 



low should not be considered equally flagrant. 
Of course many honest people have occasion, 
in emergency situations, to sell their radio 
sets at a sacrifice. What the consumer pub- 
lic must determine in each instance is whether 
the offer is bona fide. The fact is that little 
tricks of deception and misrepresentation, even 
though many of them do not constitute actual 
fraud, are undermining the confidence of the 
public in radio merchandising and, if uncon- 
trolled, eventually will prove a boomerang 



fication mark which the public has come to as- 
sociate with the product of the Radio Corpor- 
ation of America. The danger is that new 
customers, unacquainted with radio equip- 
ment, who have been told that the "201 -A" 
is what they need, may have the cheaper 
product foisted on them without knowing it. 
Perhaps the next most flagrant deception 
being practiced on the public is in the sale of 
parts, or sets manufactured from parts, which 
are sold to the public under the Neutrodyne 



294 



Radio Broadcast 



"Greatest Sale in History" 
"Lowest Prices in the City" 

"We Undersell the World" 

"Our Prices are Lower" 
Trice Reductions Hit Bottom" 
'Unequalled Radio Bargains" 
"Trade With Us Greatest Savings" 



SOMEBODY S WRONG 
Seven leading headlines from the advertising 
of seven radio stores on the same day in the 
same city. Somebody must be wrong 

trade mark. What happens is that a store 
purchases licensed parts, which go into the 
building of a Neutrodyne receiver. They 
take these parts and through the addition of 
others, perhaps of inferior quality, build a set 
which is then advertised for sale under the 
name of the manufacturer of the parts. The 
danger in this practice is found in the fact 
that the manufacturers of parts also manu- 
facture sets. 

The writer has tested this out many times to 
see how it works. For instance, companies like 
Freed-Eisemann and F. A. D. Andrea manu- 
facture Neutrodyne parts and also complete 
sets. Frequently I have entered a store in 
response to an advertisement for a Freed- 
Eisemann set and found that what was on sale 
was not a factory manufactured instrument, but 
one which had been built in the store from 
certain parts manufactured by the Freed-Eise- 
mann Company, which, however, was being 
sold in the cabinet as a Freed-Eisemann set. 
This is unfair to the radio novice because, 
having heard of this or some other particular 
set, he may be led to believe that he is getting a 
factory built machine when such is not the case. 

MANY ADVERTISEMENTS ARE NOT QUITE HONEST 

RECENTLY I undertook to study a cross 
section of radio advertising by taking the 
columns of magazines and newspapers appear^ 
ing within a week's time in order to determine 
to what extent exaggeration and deception 
may be prevalent from the standpoint of the 
consumer public. The result shows certain 
outstanding characteristics which, in the opin- 
ion of the writer, can only eventually thor- 



oughly dissatisfy the public. Most of the 
statements examined are not such as to con- 
stitute a type of misrepresentation or exaggera- 
tion which could be prosecuted. They merely 
lead the purchaser of a set or equipment to 
expect more than he actually gets, in some 
cases much more than is even possible from the 
standpoint of present technical development. 
Too many manufacturers of radio sets 
picture the ideal rather than the actual. Take, 
for example, a statement such as this: 

When the dial setting for any station has been 
determined, that station will come in on its own 
setting any time. 

As against this, it is well known that dis- 
tance reception is most uncertain, depending on 
the time of day or night, weather conditions 
and other variable considerations. The pur- 
chaser of a set who gets a station fifteen hun- 
dred miles distant to-night and cannot bring 



Precision Performance 

Having once brought in any station and 
charted the dial positions, that station may 
be brought in at any time at the same dial 
settings any time to-day, to-morrow, or a 
year from now. The set works like the com- 
bination of a safe and operates with equal 
certainty and precision. 



IT CAN T BE DONE 

This type of advertising leads many purchasers of sets to 

expect more from them than is possible in view of changing 

weather conditions, differences in the range of daytime and 

evening reception, and other controlling factors 

it in at all to-morrow night wonders why. and 
well he may, in view of the representations made 
to him in the advertisements. Over a period 
of months he must learn that a radio set can- 
not be operated with the precision of a phono- 
graph, as some manufacturers would lead the 
public to believe. Another representation that 
a set offers "perfect mastery of radio" is a 
bubble bound to burst after the purchaser has 
endured an evening full of the trials and 
tribulations which the experienced operator 
has come to take as a matter of course. 

Then we find the advertiser of equipment who 
endeavors to trace all radio troubles to the 
fact that the product of some competitor is 
being used rather than his own. He says, as 
one dealer did recently, that one hundred per 
cent, of all automobile trouble is in the ignition, 



The Way of the Transgressor 



and that the same is true with a radio set. If 
the trouble is noise, it's the batteries. Weak 
volume, blame the batteries again. No dis- 
tance, likewise blame the batteries. If the 
unthinking customer responds to this adver- 
tisement, buys the particular battery and the 
noise continues, because it comes from some 
entirely different source, satisfaction cannot 
result. 

Discontinued sets and equipment frequently 
are advertised as possessing full current value. 
For instance, in Chicago, much advertising 
was recently published of a Radiola model now 
in the background because of the newer types 
being manufactured. It was offered with the 
statement "List Price, $162.50 our price 
$37.50." At one time this set sold for $162.50, 
but it does not have such a list price now, and 
it cannot have anything like that value to the 
purchaser to-day when compared with more 
up-to-date sets. Experienced radio buyers 
who keep closely in touch with developments 
can hardly be deceived by such reductions; 
but the constantly increasing number of new 
buyers are easy prey to misrepresentation, 
which tends toward the growth of a substantial 
group in our population who eventually will 
condemn radio because they will conclude that 
its products are not marketed with fairness to 
the public. 

It has become a rather common fault to ad- 
vertise sets at a certain price and in such a way 
that the reader may well believe that full equip- 
ment is included. If he decides to take the 
set, he places his money on the counter, only 
to find that an additional outlay is required 
before his radio is equipped to operate at all. 
His reaction is likely to be unfavorable to 
that dealer. We have seen some advertise- 
ments which would seem to indicate a deliberate 
intention on the part of advertisers to list 
equipment in such a way as to lead the reader 
to believe that it is included in the price quoted 
when, however, the price given covers only the 
set itself. 

The public may well inquire when shopping 
for radio sets in response to advertising whether 
a set has its weak points as well as those good 
points which have been emphasized by the 
manufacturer. Ease of operation and the dif- 
ferent steps necessary to bring in stations may 
be featured, but in doing so some particular 
adjustment, which actual operation shows to 
be both critical and more or less unstable, 
is not mentioned. 



WHY ARE SOME DEALERS SO OPTIMISTIC WITH 
DISTANCE CLAIMS? 

CLAIMS of distance reception are all too 
often based on the exceptional rather 
than the average. Any one who has operated 
a standard set for a reasonable period of time 
knows the folly of exaggerated claims of this 
sort, and yet many a set has been sold be- 
cause the purchaser was led to believe that it 
would receive three thousand miles any time, 
any where. Such a set, operated in a nest of 
local stations and which cannot easily reach out 
and bring in broadcasting from a distance of 
several thousand miles, cannot be expected to 
come up to the hopes of the man who has been 
led to believe that he could bring in any sta- 
tion from any direction and from any distance 



Columbia Neutrodyne $140.00 

Tubes 
Batteries 
Loud Speaker 
Aerial Equipment 
Ear Phones 



HOW IT S DONE 

The price quoted is for the set alone although listing 

accessories in this way might easily lead the reader to 

believe that they are included 

almost at will. To say, as one advertiser did 
recently, that "there is no limit to the range 
of this receiving set" is playing with distance 
in a way that even the most experienced opera- 
tors with the highest powered sets would hesi- 
tate to do; or to say, as another advertiser has 
done, that a set selling for less than $75 will 
do anything that any other set will do; or that 
with the use of a piece of special equipment, 
programs will come through the air strongly 
and clearly, not marred by any static and 
without appreciable effect from electrical 
storms, warm weather, or of radio weather of 
any description, may add other names to the 
list of dissatisfied radio purchasers. 

These instances of extreme and exaggerated 
claims show the necessity for careful buying 
on the part of the public, and as the public 
comes to know the pitfalls, it will read radio 
advertising with an understanding of what to 
avoid. Honest advertising and merchandising 
are the only methods that pay in the long 
run. 




GRAHAM MCNAMEE, POLITICAL ANNOUNCER 

Whose voice, directly from the floor of the Cleveland Republican national convention has been heard by millions of 
listeners all over the country who listened to the first party convention ever broadcast by radio 



THE MARCH OF RADIO 



BY 




President, Institute of Radio Engineers 



The Growing Importance of Short Waves 



A INFORMATION accumulates, the 
possibilities of short wave transmis- 
sion seem to mount at an increasing 
rate. The high-frequency range, 
from 3000 kilocycles up, was regard- 
ed as useless only a few years ago. It was 
thought suitable for laboratory work such as 
Hertz, the radio pioneer, had carried out but 
of no" avail when it came to reliable commun- 
ication over appreciable distances. 

Reliable experiment shows this not to be the 
fact however; some of the most reliable chan- 
nels in operation over long distances to-day are 
using frequencies of approximately 3000 kc. 
and research engineers are continually gather- 



ing data to show the feasibility of using even 
shorter waves. Pittsburgh to Hastings and 
London Schenectady to California and Eng- 
land, both short wave channels seem to have 
attained a remarkable degree of reliability 
compared to what was to be expected. 

With spark wave telegraphy, such short 
waves would have been of no service at all, for 
the amount of power which could be sent out in 
the form of a 100 meter damped wave from a 
suitable antenna would have been so small as 
not to reach more than a few miles. There are 
very important reasons why these high fre- 
quencies will do so much more on continuous 
wave transmission than could be obtained with 



The March of Radio 



297 



the spark transmitter. For a given wave- 
length a much higher antenna can be used with 
continuous waves than with spark waves and 
the amount of power which can be sent off is 
hundreds of times as great with the continuous 
waves. The decrement of the spark wave was 
one of its most important characteristics, so 
much so that it was not allowed to exceed a 
certain value, as decreed by law. This dec- 
rement could not be kept low using as efficient 
radiators as are our present short wave antenna. 

With a good antenna as much as 10 kilo- 
watts can be radiated at 3000 kc without any 
trouble at all and possibly much more than 
this will be possible when we know more about 
high frequency engineering. Although many 
experimenters report the short wave channels 
show less fading than those using waves several 
times as long, the measurements of Pickard 
(none better now exist) show this not to be 
true; apparently the fad- 
ing phenomenon is about 
as prevalent in one chan- 
nel as in the other. 

With waves as short as 
35 meters, a Paris amateur 
has succeeded in talking 
to Algiers; Marconi and 
others in England have 
used successfully even 
shorter than this and we 
may confidently expect to 
see this branch of radio 
of ever increasing impor- 
tance. 

Radio Broadcast's 
"Covered Wagon" 



BEFORE this maga- 
zine reaches the 
hands of its read- 
ers, another romantic radio 
adventure will have begun. 
Captain John R. Irwin, 
the man who received the 
first C Q D from Jack 
Binns on the Republic, who 
was wireless operator on 
that famous air expedition 
in Walter Wellman's dirig- 
ible America, who was an 
officer in the Air Service 
during the war, and later 
radio officer of the Levia- 



than is now on his way across the country in 
a modern prairie schooner. He is the pilot of 
RADIO BROADCAST'S "Covered Wagon" and 
Mobile Laboratory. 

He is going to introduce radio to those Ameri- 
cans who heretofore have never known any 
more of it than could be learned from the 
perusal of newspapers, those who are not yet 
convinced that it is the wonderful thing we in 
the cities have found it to be. 

Then, too, he is going to cooperate with 
radio clubs and power companies throughout 
the country in an effort to overcome the elec- 
trical noises known as "man-made static." 

His "Covered Wagon" is an automobile 
truck with a body like the old prairie schooners. 
Samples of all the Knock-Out receivers, built in 
the laboratory of this magazine, will be on 
board and frequent demonstrations will be 
made. Captain Irwin will travel from New 




PATRICK, CARDINAL HAYES 

Catholic Archbishop of New York before the microphone of W E A F. His Emi- 
nence is shown holding the red hat which is one of the badges of the high ecclesiastic 
office to which he has recently been elevated 



298 



Radio Broadcast 



York to California and thence to Florida. He 
will make a complete survey of radio in all 
parts of the country and will give advice to 
those who are not sufficiently familiar with 
radio to determine the type of receiver best 
suited to their needs and pocket books. 

The log of the "Covered Wagon" will be of 
great value in checking the many important 
scientific, social, economic, and business prob- 
lems in which radio plays or may be made to 
play an important part. 

The American Radio Association 

FOR several months, we have watched 
with interest and admiration the effort 
being made by the American Radio 
Association to pull the loose ends of radio to- 
gether. They are making a valiant and praise- 
worthy effort to enable every listener-in every- 
where to get the most out of his receiver. 

This organization has picked out a number of 
ideals extremely difficult of attainment and 
has been on an up-hill trail from the first 
moments of its foundation. But it has done 
things so many things in fact that it now has 
the hearty endorsement of many of the leading 
stars in the radio firmament. 

Some day, perhaps, the story of Alfred M. 
Caddell, that able Secretary of the Association, 



will be told. 1 1 will be the story of the success- 
ful attaining of an ideal which owes its existence 
to but one cause the indefatigable effort to be 
of service to those vast numbers of radio folk 
who cannot be of service to themselves. 

Veterans' Hospitals Should Have Radio 
Sets 

NO WORK in which radio is a co-partner 
to-day so deserves commendation as 
the efforts to make it serve those dis- 
abled veterans of the War who are still confined 
to hospital beds. For most of us the War is 
becoming mere history, but for many it is yet, 
and will continue to be, a horrible vivid reality 
which is sapping their strength and holding 
them bedridden while the rest of us enjoy the 
pleasure of our country, preserved by their 
sacrifices. Could radio, itself practically a 
child of the War, be utilized in a more worth 
while work than in relieving as much as possi- 
ble, the suffering and tedium of the long 
hours these boys have to bear? 

Every normal American knows the answer 
to that question. Knowing it, why not do, 
each of us, our share to put radio in the hospi- 
tals where these boys pass their seemingly end- 
less days? Why not help S. L. Rothafel in 
the wonderful work he is doing? If you haven't 




YOUNG ENGLISH RADIO CONSTRUCTORS 

At work "building their own" at the Plymouth Junior Technical school 



The March of Radio 



299 



done so yet send in your 
contribution to his Hospital 
Fund so that those who 
need Roxie and his Gang 
more than you do, may 
have their burdens lightened 
and days made shorter and 
brighter as a slight reward 
for the sacrifices they made 
for the rest of us. 

Radio Inspectors Ought 
Not to Be Censors 

A : l INTERESTING 
phase of radio 
broadcasting has 
been called to our attention 
by an editorial in the Los 
Angeles Record about cer- 
tain water power rights. 
The California State Water 
and Power League is ardent 
that certain developments 
be carried out under a pub- 
lic ownership plan. They 
are opposed, naturally, by 
private power interests. 
The relative merits of the 
two schemes are much in 
debate, and probably will 
be so as long as there is 
water power to be devel- 
oped. Knowing this no one 
is nowadays either irritated 
or deceived by the fallacious arguments put 
forth by those who take either side of this 
question. 

The editorial in question denounces in un- 
mistakable terms the broadcasting of a speech 
advocating private ownership, a speech in 
which it was no doubt conclusively shown that 
public ownership would involve the public 
in ruin and debt whereas private ownerhip 
would bestow upon the same public immeasur- 
able benefits. Using a radio channel for the 
dispersion of such "misleading information" 
has thoroughly aroused those interested in 
public ownership, aroused them to such an 
extent that the radio inspector has apparently 
been convinced it was an immoral act, almost 
sufficiently to warrant the exercise of his 
censorship power. The Los Angeles attorney 
who spoke for the private interests is thus 
painted by his adversaries: 





RADIO FOG SIGNALS 

Are now being sent from Ambrose Channel light vessel. So radio supplements the 
present warnings to navigators which are in the form of light, and sound both sub- 
marine and atmospheric. The Light House Service is installing duplicates of this 
25O-watt continuous wave transmitter on various lightships at important places. 
The transmitter operates during thick weather and sends on a wavelength of 1000 

meters 



He went to San Francisco and polluted the air 
with a vicious attack on the Los Angeles municipal 
power bureau your power bureau, that is success- 
fully saving you from exploitation by private power 
profit seekers. He attacked the bond issue, which 
is about to go before the people. He attacked the 
Boulder Canyon project as a public ownership 
enterprise. He attacked the water and power act. 

The Commonwealth Club, from which he broad- 
cast is a notorious organization dedicated to 
service in the vineyards of the ruthless exploiters. 
It is a pool of economic and political stagnation from 
which arises a continuous fog of misleading propa- 
ganda. 

We are asked to give our moral support to the 
local Federal inspector who threatens to with- 
hold the privilege of the ether from men who 
present the private interests argument as did 
the Los Angeles attorney. Well we doubt 
very much the power of the Federal inspector 
to stop the broadcasting of such matter that 



3OO 



Radio Broadcast 




MAJOR EDWARD E. BOWIE 

Chief United States Weather Bureau Forecaster. For 
many years, the Bureau has used radio telegraph agencies 
to broadcast their forecasts and condition of weather 
reports, many of which went from N A A signed "Bowie." 
Now the telephone broadcasting stations are used for 
the same excellent and helpful purpose 

isn't in his province. We suppose the advo- 
cates of municipal control would be given the 
privilege of talking over the ether for present- 
ing their case, and we hazard that their talks 
might be somewhat more vitriolic than was 
that of the private interests' representative. 
One side has as much right to be heard as has 
the other. 

Europe and America Fascinated by the 
"Deadly Ray" 

BY THE time this comes from the press we 
ought to know how deadly are these 
rays, by whose mere mention Grindell 
Matthews has kept the European press agog for 
nearly a month. He seems to have given the 
English cold chills by taking his ideas to 
France, to dispose of it to a French syndi- 
cate. 

And so far he has shown just exactly nothing! 
By his mere word he has been able apparently 
to paralyze the reasoning powers of the edi- 
tors, statesmen, and militarists. He must 
be a very smooth talker or else most of his 
interviewers have been near a nervous break- 
down. 

An interview with Professor Edouard Bran- 
ly, inventor of the coherer (which the crystal 
rectifier displaced) shows the attitude of the 
true scientist. Never does he say it is im- 
possible but 

As a scientist I must have proofs before I can 



believe in this new invention. Such proof has not 
been given and consequently I cannot believe in the 
ray. As a scientist, if I consider the probability of 
the existence of the ray I must doubt the claims of 
the inventor. There is nothing in the present 
development of science to indicate the perfection 
of such a ray. Contrary to the popular belief, 
scientists do not expect such an invention. 

To have a ray that will destroy, that will stop a 
motor, that will kill at a distance, one must have a 
ray with force in it. No such ray exists. Science 
has learned how to concentrate rays to a certain 
extent, but the rays have no great force in them. 

Had the Britishers the infliction of Dr. 
Cook of polar and oil field fame, they would have 
been better able to cope with the deadly inventor ; 
they would have required him to show them at 
least a little peep at his deadly weapon before 
having such a case of nerves as he has ap- 
parently been able to produce. 

Licensing Broadcast Stations 

IN A recent issue we had a few paragraphs 
under the caption "Outlaw stations to be 
closed" it brought a very polite letter 
from the A. T. and T. Co., telling us we had not 
adequately presented their case and a rather 
more forceful letter from a reader who ex- 
presses the sentiment that if we "are paid to 
send out such propaganda for the telephone 
company, we should at least mark it so that 
the reader would know it was a paid advertise- 
ment." Well Roosevelt used to say the only 
man who never made any mistakes was the 
man who never did anything, and we suppose he 
meant it to apply to his writing as well as to his 
political acts. 

In the article in question it was stated that 
licensed stations were not allowed to broad- 
cast for profit, one of the outlaw stations so 
claiming. It appears that this was in error, 
as the present form of licenses, some of which 
were sent to us, contain no such agreement. 

The license fees are from $500 to $3,000 de- 
pending upon the size of the station. They are 
paid but once. The fee may be paid in in- 
stallments if so desired by the licensee. The 
license forms seem reasonable enough and, 
at the risk of again being accused of being on 
the pay roll of the Telephone Company we ven- 
ture to say that the fee is certainly no more 
than adequate to cover the various costly de- 
velopments which the Telephone Company 
puts at the disposal of the licensee when he is 
operating one of their equipments. 



The March of Radio 



301 



Other Opinions of the "Squier Code" 

SOME months ago we published an article 
on the Squier System of telegraphic 
codes and, according to one of our tele- 
graph friends, the lay public was very likely 
to judge the telegraph companies too severely 
on the basis of the information there given. 
He sends us an analysis of the telegraph 
traffic managers' task showing where the 
Squier System might prove advantageous 
and other places where the present system is 
better. 

The real merits of the case can only be ap- 
preciated by those having actual traffic knowl- 
edge and experience, but the summary of this 
traffic man's opinion on the question is as 
follows: 

"The point I wish to make in this whole 
matter is not so much that no saving whatso- 
ever could be had by the substitution of the 
Squier System but that from practical con- 
sideration such wholesale savings as were in- 
dicated in RADIO BROADCAST are doubtful of 
attainment and the saving, if any, would 
probably be negligible." 



sonable hope) must be evolved before our sum- 
mer time voices can be heard on the other side. 

The British Post Office committee which has 
the matter in hand has just recommended 
that a 200 kw radio telephone station be 
erected in England using the same type of 
apparatus and control as has been worked out 
and found dependable here. Our radio en- 
gineers have been telephoning across the 
Atlantic for many months, but as there was no 
transmitting apparatus in England . the con- 
versation has been a one way channel only. 

The great interference caused., by atmos- 
pheric conditions is well illustrated : by 
one statement from the engineers who have 
been doing the work. "The difficulties of 
the technical problems to be overcome are well 
indicated by the fact that atmospheric condi- 
tions often change so greatly that the amount 
of power required at one time to give audible 
speech in England may be 10,000 times as 
great as that required a few hours before." 
From this statement, undoubtedly conserva- 
tive, may be inferred the difference between 
occasionally getting a message across and es- 
tablishing commercial communication. 



Calling Up Your British Relations 



What Radio Can Do for Marriage 



A c 



CCORDING to the A. T. and T. 
officials it may be possible in the not 
distant future to sit in your own home 
and talk to a friend on the other side of the 
Atlantic. If the recommen- 
dations of the British Post 
Office to establish a suit- 
ably large radio telephone 
station are carried out, it 
will mean that telephone 
subscribers in our country 
may talk directly to Eng- 
lish subscribers. 

We have on this side of 
the Atlantic plenty of 
power to talk across with 
a reasonable degreeof 
reliability in the winter 
months. For the summer 
we must still concede the 
superiority of static; either 
stations tens and hundreds 
of times greater than we 
have at present, or some 
sort of static eliminator (for 
which there seems no rea- 



OW it does tickle the vanity of some 
folk to read their names in the morning 
_ _ newspaper. Avery Hopwood and Miss 
Rosalie Rolanda plan to be married by radio, 



H 




ANOTHER NEW USE FOR RADIO 

The Salvation Army in New York collecting funds for their recent Home Service 
anneal aided by radio concerts. This photograph was taken in front ot the New 

York Public Library 



302 



Radio Broadcast 



according to a press dispatch. He will be on 
board a ship returning from Europe and she 
will respond from one of New York's studios. 
In the actor's profession they tie and untie the 
marriage knot and with such facility and haste 
that the lack of seriousness at such a per- 
formance will not bother the principals at all. 
We have Radio Golf Balls, a Radio Cafeteria, 
Radio Pack for all sorts of ills, and many others 
of similar import so why not a Radio Wedding? 
But it is so easy to get married that we think 
it a useless waste of the ether channel. Un- 
tying the marriage knot often proves more 
difficult than tying it, however, so we suggest 
that radio be put to work along these lines, 
where it might be of real assistance. Why not 
hide a microphone behind the curtain of the 
room where Percy's wife is to have a clandestine 
meeting with the man she should have married, 
Veronica's husband? Some one could watch 
for the arrival of the hero at the rendezvous, 
properly tip off the announcer, who would then 
send out to the world his well known refrain 
"The next voice you hear will be that of - --." 
The station manager who could pull off such an 
event would, we fear, be voted the "cat's 
whiskers" or some equally expressive term of 
approbation by the millions of BCLs who were 
tuned to his wave. 

Subtraction and Legal Wrath Among the 
Big Five 



M 



ANY have remarked on the strange 
crew of bed-fellows in that offspring 
of the War, the Radio Corporation of 
America, and have often said that the natur- 
al tendency of such a group was to dissociate 
instead of to combine. According to testi- 
mony of the American Telegraph and Telephone 
officials, their company has already disposed 
of all its holdings in the Corporation, so that 
this member has already separated itself as 
far as possible from its war-time associ- 
ates. Certain patent agreements, necessary 
as a result of the war-time pooling of de- 
velopments in the interest of the Government, 
still bind it to a certain extent to the others of 
the group, but we are given to understand 
that no profits of the RCA increase the income 
of the A. T. and T. Co. 

We heard recently of a suit brought to collect 
royalties for the use of a certain patent, being 
fought by a counter suit to force the patentee to 
pay back the royalties which had already been 



paid! But the strangest one of all now comes 
to light; the Westinghouse Electric and 
Manufacturing Company in cooperation with 
Major Armstrong, has started suit against the 
A. T. and T. Co., the De Forest Radio Tele- 
phone and Telegraph Company, the General 
Electric Company, and certain individuals, 
among whom is the Secretary of the Navy. 

The patent involved is one for " an improve- 
ment in method and apparatus for producing 
sustained electrical oscillations" so evidently 
is one which may be seriously affected by the 
recent decision of the oscillating triode in favor 
of De Forest. If so, more suits loom up in the 
foreground, for all of which the public pays. 

The Radio Drama Needs a New Technique 

WE HAVE heard a great deal about the 
violence done to the sales of popular 
songs when they are sent out over the 
radio channels without a suitable royalty. 
Now we have the same reaction in the case of 
plays sent out from the broadcasting studio. 
And as we read the opinion of Mr. Edward 
Childs Carpenter, the president of the Ameri- 
can Dramatists, we are inclined to believe as 
he does, an effect the loquacious attorney for 
the American Society of Composers, Authors 
and Publishers was quite unable to produce. 

Says Mr. Carpenter "Radio is after all, but 
hearing the words of a play. A play is written to be 
performed. Without actors any play is bound to 
lose its effectiveness. The appeal of any play is in 
the action and the staging, and no play has really 
been properly presented nor has the integrity of 
the author's idea been presented without the com- 
plete presentation in a theater, with production, 
costumes, scenery, music, lights, and the other ele- 
ments that go to cast the atmospheric spell in- 
tended by the playwright. ... It is not at all impossi- 
ble that radio will evolve a technique all of its own 
in the matter of dramatic production." 

The Light Socket Receiver 

THE receiver which requires no batteries 
is sure to come, and it is sure to come 
because there is a tremendous demand 
for it and because it's possible and because 
it is sound engineering. What BCL prefers 
to continue the practice of buying new dry 
batteries (when he isn't testing them to see 
if they are any good) instead of connecting the 
set to an ordinary light socket and using only 
a switch to start and stop the set? 



The March of Radio 



303 



It seems strange that some one hasn't done 
it before, but even now, we hail as an advance 
the set which functions without either A or B 
batteries. It's comparatively simple to use 
storage batteries for the filament and plate 
circuits, mount them in a box fitted with a 
rectifier in such a manner that whenever the 
set is being used the batteries are put on charge, 
thus doing away with the necessity of periodical 
charging, but this isn't what we have in mind 
when we speak of a light socket set. A light 
socket set pure and simple, without any 
batteries at all that's the idea. Of course 
we can't expect that kind of a development to 
be pushed very hard by the dry cell manu- 
facturers because it will seriously damage 
their very large business. The inventor of 
such a set should find it easy enough how- 
ever to float his scheme (if it is good) because 
there is certainly a mint of money to be made 
out of such a device. The device needn't be 
very high in first cost and its maintenance will 
be practically nothing. There is already one 
such set on the market, and we know of another 
that looks like a winner. 

It is comparatively easy and cheap to build 



an outfit for drawing the plate current from the 
alternating current mains, but for the fila- 
ments, the required investment is quite a bit 
more. The Radio Corporation apparently 
controls an idea on a triode explained nearly 
ten years ago which uses alternating current 
for the filament. This tube gives much 
greater amplification than the ordinary kind and 
functions much better as a detector, yet for 
some reason not at all clear it is not put into 
production. Probably it will be developed 
rapidly enough when the patents on the triode 
as at present constructed expire, and the 
Corporation has to meet competition in the 
triode market. 

When this idea was mentioned in these 
columns before, it called forth a peculiar res- 
ponse from one of those participating in the 
development policies of the RCA, the main 
argument of which seemed to be that the 
general public was well satisfied with the dry 
cell tube! Of course the public hailed the 
dry cell tube with delight when they compared 
it with the older storage battery type, but 
that doesn't mean they would not prefer to 
use no batteries at all. 




TAKING THE BATTERIES OUT OF THE RADIO SET 

Harry W. Houck (left) is holding his invention which is said to do away with A and B batteries. It is a plug which fits 

into any alternating current light socket. William Dubilier, radio manufacturer, is pointing out to the audience of radio 

editors the first model of the device. Raymond Francis Yates, of the New York Herald-Tribune is standing between Mr. 

Houck and Mr. Dubilier. Orrin E. Dunlap, Jr., of the New York Times is on the extreme right 



304 



Radio Broadcast 



The dry cell outfit would still meet with much 
demand for quite some time even though the 
light socket set were put out at a reasonably 
low price because there are still localities where 
power is not available. But for the average 
city and suburban dweller the light socket set 




GENERAL PLUTARCO CALLES 

One of the prominent candidates for the Mexican Presi- 
dency at the July elections, making an address before the 
microphone of a Mexico City broadcasting station. In the 
Mexican system, four microphones are connected in parallel 

is sure to come, because it is possible, economi- 
cal, and people want it. 

Are There No More Miracles? 

IN ONE of our earliest issues it was pointed 
out how quickly the American people ac- 
custom themselves to new things, with 
what nonchalance they view a wonderful 
machine which was perfected only the week 
before. 

A radio novice was permitting his friend, a 
clergyman, to listen-in with his set and the 
wife of the clergyman was broadcasting from a 
distant station. With the same eagerness to 
show his friend some of the novelties of radio 
that all of us exhibit when we find some one who 
knows less about radio than. we do, the clergy- 
man (who probably wanted the enthusiast to 
leave the set alone so he could listen) was made 
to see the effects of mistuning, interference, and 
all the other tricks of the receiving set. He 
found that even though the antenna was dis- 
connected, the currents from the ether were 
still able to convey to the listener the words of 
the distant speaker. Seeing that the radio 
currents which were actuating the receiver 
must be coming through his body (he had the 
antenna in one hand and the antenna binding 
post in the other) he could not repress the 
statement, "And yet some people say there are 
no longer any miracles!" "Just body in- 
duction," was the matter-of-fact rejoinder of 
his friend. 



Well, we side with the clergyman. A miracle 
is something we cannot understand, and in 
spite of the fact that the phenomenon of in- 
duction has been known many years it is to- 
day as much a miracle as it was to Faraday or 
the other early workers in this field. We are 
surrounded by miracles and he who is so devoid 
of imagination (or so self-satisfied with his 
supposed wisdom) as not to perceive them 
operating around him every day is missing 
much of the interest and stimulus of this age. 

Great Minds Still Disagree on Broadcast- 
ing Payment 

WHO pays? continues to call for much 
comment and inquiry from the press. 
The New York Times printed inter- 
views recently with many of those most vitally 
interested in radio, from which the still greatly 
diversified views on this question may be 
gleaned. 

Herbert Hoover believes that broadcasting 
will be supported as it is at present and that 
the stations will be organized into six or seven 
great national circuits for using economically 
the finest talent in simultaneous broadcasting. 

H. B. Thayer, President of the American 
Telephone and Telegraph Co., while offering 
no definite suggestions, did say that he doubted 
very much the probability of using specially 
modulated waves, for which specially built 
sets, to be obtained from the broadcasting 
company only, would be required. Such 
scrambled messages are possible, he said, but 
at the same time he doubted their efficacy in 
making broadcasting self supporting. 

David Sarnoff of the Radio Corporation 
grasps the idea we put into our very first issue 
that the broadcasting station will be endowed 
as are other great public institutions. Philan- 
thropists have still to be attracted by the 
possibilities of this scheme, but times and 
people change and we may expect much. 
Radio already contributes much to the happi- 
ness of mankind, and when this is more ap- 
preciated radio will appeal to the givers of gifts 
as have done libraries and other public institu- 
tions. 

Forthe General Electric Company, Martin P. 
Rice expresses the opinion that the BCL should 
contribute to the support of broadcasting, 
either by voluntary contributions, or by the 
licensing of sets or similar scheme. 

Heywood Broun, in one of his typical tirades, 



The March of Radio 



305 



doesn't know who is going to pay the broad- 
casting artist, but he is perfectly sure someone is 
going to pay if he has anything to say about it. 
He says: 

Until radio came along this sort of graft was be- 
ginning to diminish. Communities were beginning 
to realize that it was sheer nerve to ask anybody to 
speak, or read his poems, or tell a few funny stories 
without offering a fee, however small, in return. 
Then radio burst into the world and gall returned in 
a most noxious form. The broadcasters do not pay. 
Instead they offer the performer publicity. It is 
a highly depreciated currency. People who ought to 
know better yield to the lure. 

As for the thousands of letters one is supposed 
to receive Broun is of the opinion that the 
artist can neither feed nor clothe himself with 
them and further that "it must be a fearful 
nuisance to read them all." 

E. C. Mills, for the Society of Composers, 
Authors, and Publishers, with his usual shrewd- 
ness, develops an ambitious plan of forcing the 
public to pay well for the performances of 
artists. 

China to Have Broadcast Service 

REGULAR radio broadcasting has been 
started in China; Shu Pao gets the credit 
for being the first newspaper in China to put 
itself in line with its American contemporaries. 
Four times a day music and educational lec- 
tures in Chinese are broadcast. 

The Oscillating Tube in a Legal Tangle 



M 



OST radio fans at once associate the 
regenerative circuit, and the oscillating 
triode, with the name of Armstrong, 
but according to Dr. De Forest's attorneys, 
this should not be. In their words "by 
some preliminary litigation and wide pub- 
licity given the controversy between Dr. 
De Forest and Armstrong, the public has 
been led to believe that Armstrong was 
the inventor of the so-called feed-back and 
regenerative circuits. On the other hand 
De Forest continued his fight and after seven 
years of continuous litigation has now, by the' 
court of last resort, been given credit to which 
he is so justly entitled." 

The occasion for the announcement of De 
Forest's attorneys was the recent handing down 
of a decision in the United States Court of 
Appeals for the District of Columbia. Con- 



trary to the opinion of the patent office ex- 
aminers the Court has ruled that De Forest was 
the inventor of the oscillating triode. This 
had nothing directly to do with the regenerative 
patent, which has been adjudicated in Arm- 
strong's favor, but relates to the production of 
oscillations only. Armstrong entered two pa- 
tents one to cover regeneration and one 
specifically on the production of oscillations. 
It is the latter which has been decided in De 
Forest's favor. 

Continuing, De Forest's lawyers say "it 
is impossible to foretell how far reaching the 
effect of this opinion is going to be. It is 
certain that the Radio Corporation of America, 
which is licensed under the Armstrong rights, 
and the Westinghouse Company, one of the 
members of the Radio Corporation, have 
received a set-back which may have very dis- 
astrous results." 

It seems that even this decision does not en- 
title De Forest to sit back and begin to collect 
royalties, as more litigation still faces him 
before his alleged priority in this field of 
invention is finally decided. How many more 
Courts there are still to be convinced we do 
not know, but we do know that Armstrong 
and the Radio Corporation are at present busy 
collecting data to show the next court they en- 
counter, that De Forest's contentions in the 




W. Clark Noble, a sculptor of Washington, D. C., stand- 
ing beside his recently completed work, "Listening-in" 



lower court were not sustained by reputable 
witnesses. Certainly the patent lawyers have 
reaped a rich harvest from the triode, whatever 
the real contributors to its development may 
get. 



306 



Radio Broadcast 




E. S. MARTIN 

- Secretary, Editorial Board, Boy Scouts of America - 

" Ninety-Seven per cent, of the six hundred thousand 
members of the Boy Scouts of America are interested 
in radio, which was proved by a questionnaire we re- 
cently sent out. This fact is significant to those who 
are studying the potentiality of the various interests 
of youth, for radio, more than any other interest, keeps 
the boy at home. I hail the advent of radio as offer- 
ing to the youth of America an interest which is at once 
a challenge to their intelligence, ingenuity, and skill, 
and a constant source of entertainment of value" 



W G Y Too Busy to Test 

RADIO is growing so rapidly that those 
vitally interested must continually 
strive to keep up with the new things 
discovered by others and also discover some 
for themselves. Many of the laws of radiation 
are still not clear and much experimenting has 
still to be carried out to ascertain the relative 
merits of short and long wave transmission. 
Many other important problems are in the same 
unsettled state. 

If you listen at perhaps three o'clock in the 
morning you may hear tests of all kinds going 
on from well known stations. For experi- 
ments must be carried on in the off hours 
when the BCL is in bed or at work. Even 
with this apportioning of time W G Y is not able 
to satisfy its needs. The General Electric 
Company has decided to put up another sta- 
tion, and keep it busy entirely on experimental 
work. It is expected that $150,000 will be 



required to erect the station and that it will be 
put up this summer at some point well away 
from the main General Electric plant where 
W G Y is located. Tentative plans call for a 
very flexible equipment, capable of sending 
large power at short wavelengths. The sta- 
tion will probably be very popular with 
the radio research men of Schenectady as there 
is a tremendous amount of important and 
fascinating work waiting to be attacked by just 
such a station. 

New Radio Books are Few 

OF LATE there has been but little or no 
activity in the radio field by the book 
publishers. Apparently the radio 
book market is saturated. We know stacks of 
various elementary radio books for which the 
anticipated demand did not materialize so that 
they are in dead storage and must be ulti- 
mately consigned as waste. 

In writing a radio book the author generally 
tries to explain the underlying principles of 
radio or to show how to build and make certain 
sets function. The first idea yields a book that 
requires study; not mere reading, but real 
work, for it is not to be expected that a know- 
ledge of scientific principles can be obtained 
any easier out of School than in it, and surely 
the students in school find it no easy task to 
master radio principles. The advantage of so 
mastering a book on principles is obvious how- 
ever anything gained from it is of permanent 
value and can be applied to any radio problem. 
On the other hand to read such a book is not 
as easy, nor to many as interesting, as reading 
one on how to build a set. 

The trouble with the "build your own" type 
of book is that the information given rapidly be- 
comes out of date, because of the changing art. 
New types of coils and circuits (the principles 
of which are the same as before but the ar- 
rangement and construction of which are 
different) are continually coming to the front, 
so rapidly that it is hardly worth while to in- 
vest in such a book. The better type of radio 
magazine is taking care of this field so well that 
more books on the subject will probably be 
failures from the sales standpoint. It is 
better to get a good book on principles (too 
hard for mastery at the first reading) and then 
keep abreast of the advance in constructional 
developments by reading the better class of 
radio periodical. 



The March of Radio 



307 



A Powerful New English Station 

THE Daily Mail tells us that Great 
Britain is to have the largest and most 
powerful radio station in the world 
designed for direct communication with India 
and Australia. 

The work of clearing over a square mile of 
country where the station is to be located has 
already begun. Sixteen masts, each 820 feet 
high, will be distributed over this territory 
to support the vast span of wires which will 
form the upper part of the antenna. When we 
picture this network suspended in the sky we 
can well sympathize with the small boy who 
had been taken to see one of the large trans- 
atlantic stations, and who queried of his all- 
knowing parent, "Why do they call it wireless, 
dad?" 



Interesting Things Interesting People 
Say 



pOLONEL J. F. DILLON (San Francisco; 
^ Department of Commerce: Radio Supervisor 
for the Pacific Coast radio district): "There are 
more than 500,000 receiving sets in homes, offices, 
and business houses in California. At least three 
persons listen-in at each of these receivers, which 
makes a total of at least a million and a half radio 
listeners in the state. Four million radio listeners 
on the Pacific Coast would be a conservative figure." 

. J. WEST (Columbus, Ohio; State Federal Crop 
Statistician): "One farm in every seven- 
teen in Ohio is equipped with radio. This means 
that approximately six per cent, or 7,500 rural homes 
in the state are equipped with radio receivers." 

TJOXIE NEALE FAIRCHILD (New York City; 
n Director, Home Study Department, Columbia 
University), speaking of the radio course in Brown- 
ing which he recently broadcast from WEAF, New 
York: "... People who formerly had turned 
their noses up at radio promptly turned them down 
again when they heard of that course. . . . But 
this experiment proved that a good proportion of 
the radio audience was willing to listen to literary 
discussions. Now students are turning radio fans 
and radio fans are turning students. 

"Radio as a mechanical marvel is growing stale. 
People are beginning to ask: 'Now we have it, what 
are we going to do with it?' Education is the one 
great answer to that question, and long distance 
education means books. 

"Here's another suggestion. At present some 
book stores have lectures, but this fine plan is not 



practicable for all. But there is hardly a book shop 
in the country that could not install a radio set and 
invite people to listen to these courses. And na- 
turally you would have on hand books connected 
with the topic of the lecture." 

S. HUROK (New York City; concert impressario, 
and manager of Pavlowa): "To-day, radio en- 
tertains thousands of people who never have been 
reached by concerts or the gramophone. People 
who own radio sets look up the programs to see what 
is being broadcast. They read that the aria from 
"La Boheme" will be sung that night from a certain 
station. They become interested and ask questions. 
"What is 'La Boheme'?" They look it up and learn 
that it is an opera. They want to read the libretto. 
They become interested in the soloists and inquire 
about them. In this way, an interest in music is 
created which is beneficial to concerts, because all 
these listeners are prospective attendants. 

"Of course, radio is not yet perfect, but the 
experiments now being performed will remedy the 
minor defects which exist to-day. Some of the 
transmission is poor, and I believe that the piano 
goes over the ether with less fidelity than any other 
musical instrument. Vocal selections are in most 
cases the best. . . . In the long run, I feel that 
music will benefit directly from radio." 




Underwood & Underwood 
JOHN T. AXTON 
Chief of Chaplains, United States Army 



" The degree of cheer and comfort which 

radio is giving to the disabled veterans in 

our hospitals, can hardly he realised by 

those who are well and whole " 




THE ROBERTS THREE-TUBE KNOCK-OUT RECEIVER 

Designed and incorporated in a cabinet of his own design by Mr. 
J. E. Roberts, of Cleveland, Ohio. The set cost exactly $51.90 to build 

Building a Knock-Out Three-Tube 

Roberts Set 

Suggesting Improvements in Design of the Roberts Two-Tube 
Knock-Out Receiver A Selective, Sensitive, Dependable, 
Non-Radiating Set The Parts Cost $50 and are Standard 

BY J. E. ROBERTS 



THE article appearing in the April 
issue of RADIO BROADCAST, entitled 
"A Knock-out Two-tube Set" was 
of particular interest, in that it ap- 
parently described an ideal receiving 
set of its class which offered specifically three 
outstanding advantages 

Economy and performance of a two-tube reflex, 
with a tube for detector, instead of a crystal. 

Selectivity and DX range of a regenerative set 
with two stages of amplification, without the vice of 
radiation. 

Ease of control, stability, and other virtues of a 
neutrodyne, without the complication or multipli- 
city of tubes. 



Any of these advantages alone is well worth 
trying for, so the result was that a set was 
hooked up, temporarily, on a base consisting of 
the end of a soap box, with a "false" panel, of 
v/ood, to carry the condensers exactly in ac- 
cordance in every detail, with the description 
and diagrams in the April issue, and the product 
though rather short on good looks, produced 
results much in excess of those promised, either 
specifically or by inference. 

It was apparent that this hook-up was much 
too efficient to be allowed to remain in tem- 
porary shape, and as it seemed possible to put 
it on a panel in a compact and workmanlike 
manner, with a possible further improvement 



Building a Knock-Out Three-Tube Roberts Set 



309 



due to perfect connections, proper spacing of 
instruments, etc., the set was rebuilt on a 
7" x 1 8" panel, and laid out to fit a cabinet, 
7" x 1 8" x 8" inside dimensions, and this hook- 
up was completed some weeks in advance of the 
panel layout shown in the May issue of RADIO 
BROADCAST. 

In this second hook-up several changes were 
made which promised more efficient or simpler 
operation, and while some of them did not show 
material advantages, the rest of them were ap- 
parently improvements and were incorporated 
in the set as it now stands. 

THE CHANGES MADE IN THE ORIGINAL 
DESIGN 

Fl RST, the A or primary coil was found to 
have a very satisfactory effect if it were 
arranged so that the coupling with its partner 
(Coil S-i) could be easily varied in other 
words, if a variable coupler was made of these 
two coils and this was done, by mounting 
Coil S-i directly on its variable condenser, and 
then varying the coupling by mounting Coil A 
on a bracket which would allow it to rotate 
through an arc of about 20 degrees in the same 
plane as Coil S-i . Details of this mounting are 
shown in Fig. 3. The results obtained were 
particularly noticeable when it was desired to 
make a selection between two stations operat- 
ing at the same time on a wavelength nearly the 
same with a difference of 10 to 20 meters, for 
example. 

Second, the neutralizing condenser C was re- 
placed (as suggested) by a two-plate variable 
condenser this was mounted on the panel, and 
while there is no necessity for frequent varia- 
tion of this capacity, yet it often aids in im- 



proving reception furnishing just the little 
variation that is necessary to make it "just 
right." The grid wire, spaghetti, and brass tube 
combination are efficient, but they are incon- 
venient to reach and adjust, particularly if the 
set is enclosed in a cabinet. 

Third, the fixed grid leak shown on the de- 
tector tube was replaced by a Cutler-Hammer 
variable leak, and the control brought through 
to the panel a fixed grid leak was not satis- 
factory, owing to the difficulty of getting just 
the right resistance and while the variable 
leak needed no attention after the right ad- 
justment was found, it was certainly possible 
to get just the proper resistance more easily 
and to change it in the case of a change of tube 
in the detector socket. 

Fourth, Coils N and P, and S-2 were mounted 
directly on the back of the condenser controlling 
that circuit, coils N and P being \" from the 
back condenser plate, coil S-2 on the same 
center post, f " from N and P, and centered 
with them. Coil T was then centered \" from 
S-2 and arranged to rotate through an arc of 
about 30 degrees in the same plane, and the con- 
trol carried out through the panel for convenient 
adjustment as in Fig. 2. 

Fifth, a Frost single-circuit switch was 
hooked in the common wire carrying the B 
and + A current as a matter of convenience and 
possible economy in battery current. 

In addition to these direct changes from the 
original specifications, several little details 
were noted that were of advantage. As will be 
noted from the photographs, Univernier dials 
are used in connection with the two tuning 
condensers, the condensers themselves having 
no vernier plates. This type of dial is an ab- 




CIRCUIT DIAGRAM OF THE ROBERTS TWO-TUBE RECEIVER 
With an additional stage of audio-frequency added. Note the variable grid leaks in the 
grid return of the detector tube and across the secondary of the second audio transformer 



3io 



Radio Broadcast 



solute necessity on the second condenser, since 
even with the reduction of 1 2 to i obtained by 
this dial, the difference between good and poor 
reception is a matter of a very few degrees 
with an ordinary dial, this condenser would be 
most critical, but with the vernier dial it is not 
critical merely accurate. 

The dial in the primary circuit tuning coil 
S-i need not be a vernier, as the adjustment in 
this circuit is much less fine, but the advantage 
of having two dials alike is found in logging 
stations. In the set in question, these two 
dials run approximately together, making the 
simplest sort of tuning 'for if a station is 
brought in on 80 on the first dial, the best re- 
ception will be found by locating the second 
dial between 78 and 
82. W B Z comes in 
on 60-60, WWJ on 
155-156, WOO on 
i38-i40,WHAM on 
41-45 and it can also 
be noted that there is 
a direct relation be- 
tween dial settings 
and wavelength, so 
that a dial can be set 
approximately for any 
station not logged, if 
the wavelength is 
known, and the varia- 
'tion of a few degrees 
either way, will bring 
that station in if it's 
on the air. 

Tickler coil T 
specifications called 
for 20 turns. Later, 
this was changed to 
1 8 ; in the set described, 

both 20 and 18 turns were tried and later 
reduced to 1 5 turns which, in this set, gives 
the best results. 

CONSTRUCTION EXPERIENCES WITH THE SET 

IN WINDING these spider-web coils, whether 
on home-made or purchased forms, it has 
been found that better results were obtained, 
and much less trouble, by using the proper 
gauge of enameled wire, rather than silk or 
cotton-covered. These spider-web forms are 
liable to have a sharp edge, and in threading 
the wire down into place, this edge cuts through 
the insulation of silk or cotton, resulting in two 
or more turns being shorted. The enamel is 



The Roberts Set Dressed Up 

If there has been one receiver which has 
called forth general approbation and enthusi- 
asm from our readers it was the Knock-Out 
One-Tube Set. But soon after that had 
jumped into such general popularity, along 
came Mr. Walter Van B. Roberts with 
his two-tube receiver which has all the ad- 
vantages, and more, that one could ask from 
a set using two tubes. The great number of 
enthusiastic readers who built up the Roberts 
Set, which was described in this magazine for 
April and May, lost precious little time in 
writing us the excellent results they got from 
the outfit. All of them praised its sensitive- 
ness and selectivity. And among these 
enthusiasts was Mr. J. E. Roberts, of Cleve- 
land, who put the set together, plus another 
stage of audio according to his own ideas 
which, by the way, are excellent ones. THE 
EDITOR 



much tougher, does not scrape off or "open 
up" on sharp turns and in addition takes less 
space, and looks better, and doesn't absorb 
moisture. 

Tubes were mounted on brackets made of 
\" , No. 1 8 "half hard" brass, and long 
enough to allow a little spring this prevents 
microphonic noises from the tubes, and also 
insures safety for the tubes when the set is 
moved this particular set being intended to 
be a portable set. 

It has been compared in operation to a num-~ 
ber of other sets and has been operated in sev- 
eral instances with the same conditions of an- 
tenna, ground, location etc., and in every case 
has shown its value. This two-tube set, con- 
sisting of i stage of 
RF, detector, and i 
stage of AF (reflexed) 
was fully the equal of 
a two-tube reflex set 
in volume, clarity and 
distance the reflex 
consisting of i stage of 
RF, crystal detector, 
i stage AF (reflexed) 
and one stage of 
straight AF. 

In this case, this set 
operated on the same 
tubes, batteries, an- 
tenna, ground, and 
loudspeaker as the re- 
flex and in the same 
location. 

It was then decided 
to experiment with the 
addition of another 
stage of audio fre- 
quency to this set- 
making it a three-tube set, and incorporating 
one stage of RF, one detector, one stage of re- 
flexed AF and one stage of straight A F. Fig. 
i illustrates the hook-up, and the photographs 
show the general construction details and lay- 
out, as well as general appearance of the com- 
pleted set, in and out of its cabinet. 

THE SET COMPLETE WEIGHS TWENTY-TWO 
POUNDS 

THE entire set is mounted on a 7" x 18" 
rubber panel, and included in a cabinet, 
19" long, 10" deep and 1 1" high, which cabinet 
also includes three dry cells in parallel, for 
the A battery, a 3-cell C battery block, and 



Building a Knock-Out Three-Tube Roberts Set 



THREWJED 



CONDENSER 




FLEXIBLE LEWS 



DETAILS OF THE COIL MOUNTING 

Of coils N and P, S-2, and T. H, I, K, L, and M, are 
nut bushing, knob, lock-nut and spring of standard 
switch assembly. J is ^ 2 threaded brass rod, whose 
length varies with the distance of the coil S-2 from the 
panel. A lever 3" long can be used in place of knob K 

two blocks (22^ v. each) of B battery, with 
room enough for two more blocks making 
90 volts. The completed set, with everything 
ready for the pushing of the battery switch, 
weighs about 22 pounds, and is very distinctly 
portable, being no larger or heavier than the 
well known Gladstone bag and not so heavy 
as many of those bags, when filled. 

The three-tube set is nothing more nor less 
than the two-tube set as originally built, right 
up to the output jack. A two-circuit jack was 
substituted for the single circuit jack on the 
original set, and the second stage of amplifi- 
cation, which is the regular second stage 
standard hook-up in every way but one, was 
connected in the standard way to the terminals 
of the two-circuit jack, as shown in Fig. i . The 
only exception to the regulation AF hook-up 
is the inclusion of a grid-leak, across the 
secondary terminals of the second transformer. 
Almost as good a result can be obtained by 
shunting a .002 mfd. fixed condenser across 
these terminals, but a variable grid leak is to 
be preferred. 

The location of a grid leak in this position is 
of very great advantage in preventing distor- 
tion, particularly on strong signals. 

WHAT THE SET WILL DO 

THE resulting set is most satisfactory in 
every way it is compact, and easily 
handled and portable in the strictest sense 
it uses three tubes, and gives the equivalent of 
four and five in volume it is easily tuned, and 
a station once logged, can be returned to again 
and again, quickly and easily it is stable; once 
tuned-in it can be forgotten till the end of the 
program it is selective, as it will bring in 



out-of-town stations through powerful locals, 
even when the wavelengths differ less than 20 
meters. Two tubes are all that is necessary 
for loudspeaker results from stations up to 
several hundred miles, consistently, further, 
on occasions; three tubes will bring in anything 
up to 1 500 miles on the horn and many of the 
smaller powered stations in the same radius 
on the phones. 

Following is a copy of the log-book of this 
set for three days (or nights) : 

Primary 4 Cond's 81-87 



May ist 


WGY 


380 m 




WBZ 


475 




KYW 


536 




WOO 


509 




WIP 


509 




WHN 


360 


May 2nd 


8AJ 


Amateur 




8BOP 


" 




WDAP 


390 




WHAS 


400 




WSB 


429 




WDAF 


411 




WOS 


441 




WGN 


370 




WDAR 


395 




WJZ 


455 




WGR 


319 




WLAG 


4'7 




WLS 


345 




WOQ 


360 




WHB 


411 


May 3rd 


WHAM 


283 




WWJ 


517 




KFKX 


34' 




WCX 


5'7 




WSAI 


309 




WCAE 


462 



4 


60-60 


5 


1 70- 1 68 


5 


138-140 


5 


138-140 


3 


62-62 


4 


21-13 


4 


21-13 


4 


70-67 


4 


86-85 


4 


i 10-108 


4 


95-91 


4 


i 10-1 14 


4 


75-73 


4 


86-8 1 


5 


i 14-1 19 


4 


52-50 


4 


100-98 


4 


65-61 


4 


65-65 


4 


93-93 


4 


45-41 


4 


155-156 


4 


61-61 


4 


155-156 


4 


48-45 


5 


120-120 



In all cases noted, this reception was ample 
for the phones on two tubes in about half 
the cases, it was sufficient for loud speaker 
reception. On three tubes, they were all amply 
loud for comfortable reception with but one 
exception (WLAG) which was poor on this 
occasion. In all cases excepting WGY,W DAP 
WGN and WOQ, reception was through local 
broadcasting. 

PARTS REQUIRED 

FOLLOWING is a list of parts used in the 
three-tube set illustrated, at local prices. 
This list shows that the three-tube set can be 
built out of reasonably good material complete 
for less than $50.00, exclusive only of the 
cabinet and phones (or loud speaker units). 

It is to be noted that this entire description 
refers to several sets. One of them was tem- 
porary, another, a complete two-tube set on a 
panel and a complete three-tube set, on a panel 
and in a cabinet, which were operated with 
the results as outlined, on two, and later, three 



312 



Radio Broadcast 



WD-I2 tubes. Trial was made on the two- 
tube set, of a pair of boot-leg tubes of the 201 -A 
type with results less satisfactory than those 
produced by the WD-i2's. The two-tube set 
was also tried with two 201 -A Radiotrons, with 
a 6-volt storage battery on the filament, and 90 
volts on the plate of the first tube. The re- 
sults were but very little better than the 
results produced by the WD-i2's. 

PARTS REQUIRED 



2 23 plate RVC variable condensers 
2 Univernier Dials 
3 Fada sockets 
3 Rheostats . . .... 


$ 4.00 
2.50 
2.25 
1.50 


5 Spiderweb coil forms 


J 

.50 


Wire (enameled) for coils 


.50 


Cutler-Hammer grid leak 


1.50 


Double circuit jack 


75 


Single circuit jack 


.50 


Jefferson Transformer 6:1 


3.50 


Jefferson Transformer 3:1 


2.50 


Frost Battery switch 


25 


Inductance switch for primary taps . 


75 


2 Switch levers (for coupling control) . 


75 


2 plate condenser variable 


1. 00 


Dial for same 


25 


Micadons (.00025, -0025, .005 mfd.) . 


1.15 


Bradleyohm 


2.OO 


Phone plug 


.50 


Flexible connections 


.40 


Panel 7 x 18 


'35 


Miscellaneous bus bar binding posts, 




bolts, etc 


I.OO 



$29.40 

3 WD- 1 2 tubes 15.00 

3 Dry-cells (Burgess) 1.50 

3 blocks B battery 6.00 

$51.90 

The latter tubes seem to vary in character- 
istics, as it took some shifting of tubes to get 




BEHIND THE PANEL 

From the under side, showing the spring-brass brackets holding 
the tube shelf and three rheostats. The neutralizing condenser 
is in the center. The tickler coil is on the left and the two audio 
transformers are one on either side of the rheostats 



the three tubes sorted out for their best opera- 
tion. It was found that one tube was de- 
cidedly below average as a reflex operator, but 
functioned perfectly as a detector, and vice- 
versa with the second tube, while the third 
will do anything, anywhere. The set is easy 
to control, simple to tune, and it does not 
radiate. 

This particular set is operating about three 
miles from the center of Cleveland, Ohio with- 
in a mile of WHK, two miles and a half from 
WJAX and less than 5 miles from WTAM. 
It operates on a 75-foot single wire antenna, 
with a 4O-foot lead-in, down the brick side-wall 
of an apartment house, surrounded on three 
sides by 55O-volt trolley lines, and on the fourth 
side by a 22oo-volt power cable with trans- 
formers less than 500 yards away. It is within 
three miles of WT K, a most pervasive ship-to- 
shore spark station operating on 600 meters, 
and apparently in the center of the largest col- 
lection of radiating sets with dial-twisting 
operators in the whole United States it will 
get away from everything but the shock exci- 
tation of WTK's spark. Nothing can elimi- 
nate that. 

HINTS ON BUILDING THE SET 

IN THE building of these three sets sev- 
eral little kinks have been discovered that 
may aid in construction of duplicate receiv- 
ers of this type. 

The forms for the spider-web coils are not 
easy to make, for the best material is hard to 
handle with the usual tools. They are more or 
less difficult to find in the regular radio stores, 
for some unknown reason, but they have been 
found in the five and ten cent stores in three 
cities, and are probably carried by all of the 
stores of that class that carry radio parts. 
Three types of these forms have 
been found: one is made of what 
appears to be a soft cardboard, 
much like a double-thick stiff blot- 
ter. It is wise to avoid this sort of 
material another is made of a A" 
(thick) red vulcanized fibre, and is 
very good, but the best, if they can 
be found, are the ones made of iV' 
(thick) hard rubber. The size that 
is best, and which is amply large for 
the windings specified, has a if" 
center, 4" outside diameter, and 
fifteen slots. 

It makes no difference in winding 



Building a Knock-Out Three-Tube Roberts Set 



313 




DETAILS OF THE BRACKET F 
As shown incorporated in the drawing below. The 
lever G is #18 gauge brass. Its other dimensions 
will vary with the location of center of coil S-i 



these coils whether they are wound clockwise, or 
counter-clockwise, but, whichever direction you 
choose, wind all of them the same way. 1 1 is a very 
good scheme to wind them clockwise, leaving 
the inner terminal wire protruding from the 
face of the form (the face being the side toward 
you), and wind in a clockwise direction till the 
required number of turns are placed, and then 
bring the outside terminal wire through to the 
face of the form. Make a terminal out of a 
|"-A brass bolt and nut and locate same for 
the beginning of the coil, about \" inside of the 
windings, soldering the end of the wire fn the 
screw slot duplicate the process for the out- 
side end of the wire, locating the bolt about 
\" outside of the windings on one of the spokes 
of the form. Then mark the coil, on the face, 
with an arrow pointing in the direction of the 
windings, and when assembling the coils, see 
that all the arrows are on the same relative side 
of the coils and all pointing in the same direc- 
tion. 

In the double coil, (N and P) it is well to 
bring the outside terminal of N,, and the inside 
terminal of P, to a common terminal bolt, 
inside the winding circle, and locate the ter- 
minal bolts for the inside terminal of 
N and the outside terminal of P, out- 
side the winding circle, on two adja- 
cent spokes of the form, and mark 
them. 

The wiring diagram should be fol- 
lowed carefully, in every case, but 
most particularly in the wiring of the 
filament lead. Do not run this wire 
to or through rheostats or resistances 
of any kind use either square bus 
bar, or No. 14 hard copper wire, and 



run direct from the -A terminal binding post to 
the - terminal of the filament on the tube sockets 
(on standard sockets, the - post is the one near- 
est to the grid terminal often both terminals 
are only marked with an F without + and - 
markings), and then carry it on, if consistent, to 
meet the other - A connections^on the two-tube 
set these connections are to the F terminal on 
the secondary of the transformer, one side of the 
.005 condenser, one side of the .0025 condenser, 
and the grid return of the detector tube the 
three-tube set has another one to the second 




DETAIL OF THE MOUNTING 
And coupling of coils A and S-i . H, I, ], and 
K a re nut, bushing, shaft and knob of standard 
switch lever assembly. ] is coated with 
solder and filed to a sliding fit in bushing I 

transformer.) The rheostats, whether you' use 
one or three resistances, if you use them, and 
the battery switch should all go in the line 
carrying the A - and B - currents. 

In the set described, using two (and three) 
WD-12 tubes, 22! volts of B battery seemed to 




BACK VIEW OF THE RECEIVER 



3'4 



Radio Broadcast 




ALTERING THE DESIGN 

Several of these three-tube sets have been built in RADIO BROADCAST'S Laboratory and the illustration 
above shows very plainly that it is not absolutely essential to follow the lay-out suggested by the author 



be correct for the plate voltage on the second 
tube, and both the two-tube and three-tube sets 
have given splendid results with 45 volts of B on 
the first (and third) tube. When 201 -A tubes 



were used in the two-tube set, 90 volts were ap- 
plied to the plate of the first tube and 22! volts 
on the second tube and the results were only 
slightly better than 45 volts on the WD-I2. 




Was built under the direction of RADIO BROADCAST by Schneider and Horneij, of New 
York. The design and workmanship is exceptionally clean cut and workmanlike 



-When ihe 'America* Pui Oui io >Seca 
Fog Wind Disaster and Rescue. 




Told 



ff Wireless Man 



JULY 14, 1919, those two admirable Lieutenants, Alcock and Brown began their 
airplane trip from St. John's, Newfoundland, which ended with their successful arrival 
at Clifden, Ireland. On October loth, 1910, a much bulkier airship and a more numerous 
crew started to cross the same stretch of ocean, but they were nine years ahead of the progress 
of invention and failed in their attempt to reach the other shores. This story is particularly 
interesting at this time because of the "round the world" airplane flights being staged by the 
U. S. Army Air Service, and others. 

"I have often before been approached to write about this eventful voyage of the 
America," writes Mr. Irwin to the Editor, "but have refrained, believing that the story 
would make more interesting reading later." 



rTHE spring of 1910 I received what, at 
:hat period in the history of radio, was the 
strangest assignment a wireless operator 
iver had. I had returned to New York 
after a trip to England as radio operator on 
the old American Liner St. Louis. The Mar- 
coni Wireless Telegraph Company of America 
was then a small organization and I was one 
of the four sea-going operators in its employ 
(there were only fifteen operators in the com- 
pany's entire service). To be in charge of one 
of the four ship stations the company controlled 



was considered, in those days, a good job. I 
was contented with my lot and satisfied with 
what life offered a fine ship, good fellows for 
shipmates, and a pleasant run. 

It was then customary, in that small family- 
like organization, for ship operators to report 
after each voyage direct to the Chief Engineer 
of the company, Mr. Frederick M. Sammis. 
He occupied a similar position to Poo Bah 
that extraordinary and versatile character in 
Gilbert and Sullivan's "Mikado." He acted in 
almost every capacity. Without any other 



Radio Broadcast 



thought in mind, except, perhaps, the usual 
operator's genius for smelling a salary advance, 
1 entered Mr. Sammis' office and made the 
customary report. It was then 1 received the 
jolt he had prepared for me. He nonchalantly 
inquired whether I was prepared for a transfer 
to another ship, and as though it was an every- 
day duty with him, in a few words tendered me 
the job of operator on the airship America, then 
being constructed at Atlantic City. Whether I 
jumped at this offer or not I cannot remember 
now, but I found myself in the course of a day 
or two in Atlantic City, duly signed on as a 
member of the crew of a dirigible and com- 
mitted to make the first at- 
tempt to cross the Atlantic 
by air line. 

ASSIGNED TO AN AIRSHIP 
IN IQIO 

MY CONTRACT with 
Mr. Walter Wellman, 
who commanded the expedi- 
tion, called for my services 
not only as a wireless man, 
but as a general aide, and the 
months intervening between 
June, when I joined the crew, 
and October i5th, when we 
sailed, found me handling 
many jobs and assimilating 
a knowledge of aeronautics. 
There was also born in me a 
love for the flying game that 
has persisted to this day. One of the jobs nearly 
cost me my trip when the valve on the hydrogen 
plant, which 1 was tending, came off in my 
hand and filled my shoe with a boiling sulphuric 
solution. I was weeks in a hospital and my 
substitute had already been selected, but for- 
tunately many delays in the sailing date inter- 
vened, with the result that I was able to hobble 
down to the ship and sail with the originally 
selected crew. 

The America was what is known as a non- 
rigid type of dirigible, cigar shaped. She was 
228 feet long and 52 feet in diameter at the 
central or thickest part. This great gas reser- 
voir was made of cotton, silk and rubber and 
beautifully tailored, all seams being'wide lapped, 
sewn and gummed, and extra strips cemented 
over to cover the stitches and prevent leakage of 
hydrogen. The huge envelope contained when 
fully inflated, 345,000 cubic feet of hydrogen 
gas. This lifted a load of 28,000 pounds. 




Under the balloon or gas envelope was built 
a huge steel frame, enclosed with varnished 
linen, and attached to the balloon by eighty 
steel cables fastened to what is known as 
the "relingue," or, in other words, a belt sewn 
to the balloon about ten feet below its equator 
and extending its full length. This frame was 
fashioned of the best steel tubing and wires, 
strung as a bridge, the whole being 1 56 feet 
long, 8 feet wide at the top, V shaped, and at 
the bottom of the V there was a staunch steel 
cylinder two feet in diameter, divided into ten 
compartments, with a capacity of 1,500 gallons 
of gasoline. Along the top of this cylinder ran 
a thin boardwalk 2\ feet wide, 
forming the floor or deck of 
the car. Celluloid windows 
were placed at intervals in 
the linen sides of the car en- 
closures ; and about the engine 
rooms, amidships, steel screen- 
ings replaced the linen. Non- 
inflammable paint was em- 
ployed to minimize fire risks. 
In this car were the crew's 
quarters, engine rooms, 
dynamo, and control or navi- 
gating bridge. 



JACK IRWIN 

Who tells his story of the first wireless 

voyage in the air when Walter Wellman's 

America set out to conquer the Atlantic 

in October, 1910 



THE EQUIPMENT OF THIS 
PIOX'EER SHIP 

SHE was engined with two 
motors, one a Lorraine- 
Dietrich enginedriving, at 500 
revolutions per minute, a pair of propellers each 
1 2 feet long. The other engine was an E. N . V. 
8-cylinder motor, driving twin propellers 10^ 
feet in length at 750 R. P. M. We also had a 
small gas engine to operate air pumps for the 
balloonettes. This small engine acted as a 
donkey engine for cranking the big engines. 

Slung under the central portion of the car 
was the lifeboat. This lifeboat was then the 
last word in boat-building. It was built of 
sewn, laminated mahogany 27 feet long, 6 
feet wide, with a depth of 3! feet amidships. 
Each end was decked over and made into a 
water-tight compartment by simply battening 
down a circular hatch in each deck. Amidships 
was a spacious cockpit in the center of which 
was a self-baling device and in the forward 
end a cubby-hole for the wireless apparatus. 

Below the lifeboat, made fast to the long 
steel car fore and aft, swung the equilibrator, 
designed to equalize our altitude. This device 



When the "America" Put Out to Sea 




Underwood & Underwood 



THE CREW 



Of the America, photographed near the hangar at Atlantic City, where the ship was built. Left to right, Melvin 
Vaniman, constructor, and chief engineer; Murray Simon, navigator; Walter Wellman, head of the expedition; Fred 
Aubert and Louis Loud, assistant engineers. Wireless operator Irwin burned his foot in an explosion of hydrogen and 

was not in the photograph 



also served for our radio ground connection and 
provided storage for our reserve gasoline sup- 
ply. This equilibrator consisted of a great 
many steel cylindrical tanks, concave and con- 
vex at either end, threaded like cotton spools on 
a 340 foot f-inch steel cable. 

The radio apparatus, designed by Mr. 
Sammis, was considered the ultimate in equip- 
ment in those days, but how I have laughed 
since, and yet marveled at its simple efficiency. 
Those who read this will also smile at the de- 
scription of the set, nevertheless, pause and 
consider that this was the first time that the 
radio engineers of that day had been called 
upon to equip an airship of any kind. We had 
nothing to guide us no precedent to follow. 
There were innumerable problems to solve, the 
greatest being the elimination of fire hazard by 
sparking in the rigging adjacent to the gas 
container. Hydrogen gas, when combined 
with a certain mixture of air is a mighty ex- 
plosive, as I was to learn in the subsequent 
Akron expedition. Other problems to over- 
come were limitations in weight and size. Like 
radio arrangements on any ship in those days, 
the wireless accommodation was given the least 
consideration at the time of drawing the ship's 
plans. Radio was indeed an experiment. The 
events of the voyage changed this attitude. 

THE FIRST AIRSHIP RADIO SET 

BECAUSE we had absolutely to eliminate 
fire hazards the transmitter was of the 
inductively coupled spark type and con- 
structed to provide exceptionally loose coup- 



ling. A specially built induction coil was 
installed inside a square cabinet about 12 by 12 
inches by 18 inches high. This cabinet was 
hinged six inches from the top. In the lower 
part with the induction coil the condensers and 
spark gap were installed. The leads from the 
spark gap and the condenser were taken to the 
primary of the oscillation transformer, consist- 
ing of a few turns of heavy wire wound round 
the inside of the lower portion of the cabinet. 
The secondary of the oscillation transformer 
was wound round the hinged lid of this trans- 
mitter cabinet, and variation of the coupling 
was obtained by the raising or lowering of the 
lid. One lead of this secondary was taken to 
the car of the airship and made fast to the 
tank, making the entire metal and wiring of the 
great car the antenna. The other lead from 
the secondary of the oscillation transformer 
was made fast to the equilibrator which was 
used as a ground when trailing on the sea, and 
as a counterpoise when suspended out of the 
water, care having been taken to insulate it 
from the car to which it was anchored. In 
series with the ground connection we inserted 
a small air-gap to indicate antenna radiation 
as we possessed no reliable radio-frequency 
meters in those days ! 

Theoretically, in arranging the coupling of 
the transmitter it was necessary to give careful 
attention to the fact that the dragging equili- 
brator, which formed part of the open oscillat- 
ing circuit, would be continually varying in 
length, dependent upon the lifting power of the 
hydrogen in different degrees of temperature, 



3 i8 



Radio Broadcast 



thus causing a corresponding variation in its 
natural period. A very loose coupling was 
finally determined upon in order to nullify as 
far as possible the effect of the open oscillatory 
circuit upon the closed. We later had to cast 
aside all these fine theories for a more simple 
expedient. 

In actual tests on the ground it was found 
the original induction coil was not very efficient 
and a standard Marconi lo-inch coil was added 
to the set, the original being retained as a spare. 
A battery of Leyden jars was also provided for 
a condenser. Tests proved that this assembly 
was capable of transmitting a distance of from 
50 to 75 miles in daylight without difficulty, and 
as we planned to keep to the steamer lanes 




Underwood & Underwood 
ENGINE ROOM 
Of the ship, looking aft. The crew had very little space for promenades 



across the Atlantic this was considered satis- 
factory. 

The actual power used was approximately 
250 watts. The energy was obtained from a 
small storage battery of 24 volts, which, in turn, 
was charged by a small dynamo belted to one 
of the main engines. This outfit also supplied 
current for a few electric lights in various parts 
of the ship. 

OUR RECEIVER SIMPLICITY ITSELF 

THE receiving apparatus was simplicity it- 
self and consisted of a single circuit con- 
taining a variable inductance, a variable con- 
denser and a specially built magnetic detector. 
These were arranged on the baseboard of the 
wireless cupboard and con- 
nected with flexible leads. 
As I have previously re- 
marked, we hoped to stay on 
the transatlantic steamer 
tracks. Distance reception 
and selectivity were of sec- 
ondary consideration. As 
ship and shore stations in 
those days worked on the 
wavelength which gave them 
the greatest efficiency (this 
was before the London Con- 
vention and U. S. Radio 
Laws), a receiver broad in 
its tuning was desirable. 

With this equipment in- 
stalled, the America was fi- 
nally ready for the hop-off. 
The start had been scheduled 
for August or early Septem- 
ber and trial trips had been 
planned, but due to annoy- 
ing delays the ship was not 
ready for the air until Octo- 
ber. Since it was so late in 
the year, the proposed trial 
flights were abandoned. 



OCTOBER FIFTEENTH 4 A. 
M., FOG, AND THE START 

ON THE morning of 
October 15,1910,! was 
awakened about 4 o'clock 
and told to go aboard. There 
was not a breath of wind. A 
dense fog dripped down over 
everything. The crew of the 
ship consisted of Messrs. 



When the "America" Put Out to Sea 



3'9 



Walter Wellman, commanding; Melvin Vani- 
man, chief engineer; Louis Loud and Fred 
Aubert, assistant engineers; Murray Simon, 
navigator; and the writer. With the help of a 
few hundred police and firemen we proceeded 
to launch the largest non-rigid airship ever 
constructed. At 8 A. M. all was in readiness 
and the crew climbed aboard. The last to 
embark was our mascot, a pretty foundling 
kitten that had been a pet around the hangar. 
The crew had jokingly told visitors that the 
kitten was going along with us and just as the 
word to "let go" was passed, somebody in the 
crowd threw the kitten into the lifeboat where 
I had taken my station. Up we went and the 
cat was one of us! Kitty, at first, appeared 
scared and raised an awful " holler," but he (yes, 
it was a Tom!) soon settled down. In the long 
days and longer nights that followed, I will ad- 
mit I was grateful for that kitten's affectionate 
company. It was always to be found cuddled 
up to me in the wireless corner of the boat. 

We did not start our motors immediately, 
but preferred to be towed out through the 
narrow entrance called The Inlet, at Atlantic 
City. Reaching the open water our tug cast 
off our line and we started our engines. We 
were flying at an altitude of only 200 feet, 
with a portion of the equilibrator trailing on 
the surface of the ocean. This low altitude 
was due to the heavy cargo we carried and the 
fact that the morning was cold and wet. The 
moisture of the fog contracted the hydrogen 
with a consequent loss of lifting capacity. 

During the first hour of the flight I was busy 
making various adjustments. Listening in, I 
could hear " Bobby" Miller, at the old United 
Wireless station "AX," on Young's Pier at 
Atlantic City calling "W," the call letter as- 
signed to the America. The signals dissipated 
any doubts I may have had regarding the re- 
ceiver. 

For months we had discussed the possibility 
of sparking in the rigging and the risk of burn- 
ing a hole in the fabric of the balloon, so when 
the moment came to "sit" on the key of the 
transmitter, I think I can be pardoned for 
my nervousness. I am sure I have exper- 
ienced the moment that a suicide passes 
through when he is about to pull the trigger. 
Stationing the crew in different parts of the ship 
to report any sparking, I threw in the sending 
switch and answered Miller's repeated calls. 
I shall never forget my expansive satisfaction 
when he came back and told me my signals 




THE CAT AND THE ENGINEER 
The homeless Atlantic City cat which unwittingly acted 
as mascot on the voyage, being comforted by chief en- 
gineer Vaniman 

were clear and strong. I had opened the 
coupling of the transmitter for a minimum rad- 
iation; therefore, with only a few miles separat- 
ing us from the nearest station, I had estab- 
lished radio communication, for the first time, 
between a ship of the air and the earth, but I 
had plenty of power in reserve and knew that 
we had reliable communication within certain 
limitations. Mr. Wellman, during the time I 
had been engaged in these preliminary tests, 
had been sitting at my elbow, anxiously waiting 
the result, but as he afterwards wrote in his 
book describing the trip, he could tell by the 
pleased grin on my face that we had succeeded 
in establishing communication. 

FIRST SENSATIONS IN THE AIR NONE 

BY REFERENCE to my log, I find that 
communication was established with 
AX at 10.30 A. M. and that at 11.05 A - M - ' 
had sent eight messages to Miller. At 12.30 
p. M. I made an entry of receiving two messages 
from AX, while at 1.30 P. M.. there was this 
notation in the log, " Received one message and 
sent two to Atlantic City. Everything going 
fine, sensation very fine, all happy." Thus 
was the first airship traffic conducted, and it 
had soon developed into the ordinary routine. 
1 had been very busy, these hours, without time 
to reflect upon my strange surroundings or give 
thought to the unusual experience of flying. 



320 



Radio Broadcast 



I have spent hundreds of hours in the air since 
and been asked innumerable times what my 
first sensations were, but I can truthfully say 
I cannot recall them, if 1 had any. My only 
anxiety was regarding the success of the in- 
stallation of wireless; once that was assured 1 
felt nothing but elation. While I was busy 
at the radio key, successfully maintaining con- 
stant touch with Atlantic City, things were 
not going so smoothly with the engineering de- 
partment of the ship. 

After several hours in the air the dense fog 
in which we started condensed upon the huge 
surface of the dirigible, adding a great weight 
to an already overloaded ship. Instead of 
steadily rising, as the heat of the sun increased 
and expanded the gas, we slowly descended and 
lost altitude. We were compelled to jettison 
some of the cargo. Due, also, to the lack of 
trial flights, the engines required tuning and 
we proceeded very slowly during the morning 
of the first day. Several times during that 
morning either one or the other of the engines 
had to be stopped, caused by sand in the bear- 
ings. Our hangar at Atlantic City was in a 
most exposed spot where every wind that blew 
brought clouds of sand. However we contin- 
ued to make progress. 

At 3.30 P. M. on that first day, 1 received my 
last message direct from Atlantic City. At 
that time I find that a notation in the log states 
that 1 was no longer able to hear him, because 
his signals were weak. The motors made a 
fearful noise. The only means 1 had of dead- 
ening the sound of those big engines was the 
slight protection provided by the cotton 
battens, 1 had fashioned. From then until 
8 P. M., with the exception of intermittent 
motor trouble, the voyage -was uneventful. At 
that time, still in a dense fog, we almost ran 
into a large sailing ship. So close did we pass 
that we could see the crew running round the 
decks. Later we passed very close to a large 
steamer, which we eventually learned was the 
Coamo. From time to time 1 tried to get into 
communication with various shore stations, 
without success. It is quite possible that 
some of them answered me, but the engines 
killed anything but the very strongest signals. 

AN ENGINE GONE BAD 

DURING the night, our best engine had to 
be stopped, permanently out of com- 
mission. It appears that the bearings of the 
propellers had broken, causing one of them 



to wabble alarmingly. Up to this time there 
had been no wind at all, but now it began to 
freshen up a bit which drove us eastward, but 
in a northerly leeway. The fog still persisted 
and we were compelled to jettison some fuel 
to prevent descending into the sea. Another 
danger which became apparent when night fell 
was the stream of sparks from the exhaust. 
We were afraid that they would cause an ex- 
plosion and Wellman wanted to stop the re- 
maining engine. Vaniman, however, talked 
him out of this, explaining that we had been 
running all day and that, if we stopped the 
engine we would undoubtedly drift over Long 
Island. Furthermore, the balloon by this time 
was so saturated with water from the condensed 
fog that we ran little risk of fire. So, through 
all that night we proceeded under one engine. 
The engine that had gone back on us was the 
one to which the dynamo was belted and that 
meant that we would be unable to charge our 
battery. With this in mind, I began to hoard 
the "juice" and used the wireless only when 
positive that there was something to use it for. 
As subsequent events proved, it was well I did. 

At 5.05 A. M. on the i6th, my log shows 
that the engines had stopped and that I 
was listening to all stations talking about us 
and calling W. I heard the Sagaponack 
(Long Island) station inform Siasconset that 
we were 60 miles South of Scotland Light at 
6.50 P. M. the previous night when we had been 
sighted by a steamer and reported by radio. 
All this time the wind was steadily increasing 
but was in our favor and we made such good 
time that we decided to allow our remaining 
engine to cool off. I waited until Siasconset 
station was very strong before I attempted to 
communicate. At 10.35 A. M. I established 
communication with SC (Siasconset, Nan- 
tucket Island) sending him several messages. 
We were very close to that island during the 
day, so close, indeed, and so strong our signals, 
that I afterwards learned that the boys at the 
stations ran outdoors to try to sight us. 

Our expedition had been financed by several 
newspapers and Mr. Wellman, a newspaperman 
himself, commenced to file voluminous mes- 
sages to them. I sent the short ones, but as 
they became lengthier I protested that the 
batteries were running down and that we should 
conserve our power in case we needed help. 
He promptly agreed with me. 

The wind now increased to a gale and began 
to bear us southeast. When night fell we 



When the "America" Put Out to Sea 



321 



again experienced trouble in remaining in the 
air. We were -compelled constantly to throw 
supplies overboard. 

c Q D 

THAT night I attempted to obtain assis- 
tance, calling C Q D, which at that time 
was the signal of distress. Our engines were 
now useless. The voyage had failed and our 
one concern was to get away with our lives. 
1 early realized that there was no hope of assis- 
tance while we were in the air and that we 
would have to take to the lifeboat. However, 
with the sea then running and the gale blowing, 
we simply had to stay in the air. Engineers 
Loud and Aubert commenced to take the 
large motor apart and throw it overboard, to 
lighten the ship. At daybreak on Monday, 
the third day out, I find I made a note reading, 
"7 A. M. All ready during the night to leave 
in the boat, but the breeze too strong for 
launching. Listened-in and heard the S.S. 



Main (German) very strong. Now hear Cape 
Sable sending a message to some ship for us. 
Copy it. It is from the New York Times and 
is about the weather." 

At 7.20 that morning our navigator took 
his first sight for position and made us in 
Longitude 65.51 West. This was 210 miles 
east of Nantucket. We were steadily drifting 
south in a beautiful sunny morning. The 
warmth of the sun took us upward, indeed, so 
fast did we rise that we had to let some of our 
gas out to steady our ascent. It was about 
this time that I received the greatest scare of 
my life. Mr. Vaniman in pulling the valve 
cords to release the hydrogen, pulled on the 
wrong control and we came down in such a rush 
that it looked as though we were to be emptied 
into the sea. Mr. Wellman and myself were 
in the lifeboat, which, slung as it was under the 
car, would be the first thing to hit the sea. 
Without a word we made for the ladder leading 
to the car above. It was then I forgot about 




Charles H. Huesgen from Underwood & Underwood 

"AIRSHIP OFF THE PORT BOW, SIR" 

This remarkable photograph was taken from the deck of the rescuing ship Trent, which picked up the six men in the 
open ocean. The crew of the airship can be seen preparing to release the clutches which held their special lifeboat 



322 



Radio Broadcast 



my injured foot. I went up that ladder like 
a monkey but when 1 had reached the car 
above, 1 found the excitement was over, we 
had bounced off our equilibrator which had 
acted as a bumper on the sea. We made a 
series of long bounces much like a bouncing 
tennis ball. Mr. Wellman, who had in the 
meantime got caught in the manhole in the 
bottom of the car, with his head and shoulders 
above and held fast under the car by his pro- 
jecting hunting knife (we each carried one), was 
not so happy. He did not know that the 
danger had passed. He called for assistance 
to extricate him and Loud and myself, laugh- 
ingly, released him. I was laughing through 
reaction after the previous terrifying moments, 
but Mr. Wellman in a story he wrote after our 
return to New York, said "Irwin laughed 
in the face of death." Thus are heroes 
made! 

From that time on, we drifted in a south- 
easterly direction. From my log I find that 
1 listened in all day and into the evening. The 
last note made in the air in the radio log reads: 



" 7 P. M. Hear wireless stations working from 
Cape Sable to the Southern States." In that 
early day, that meant that I heard just about 
every station in North America. 

The following, taken from my log, tells the 
remainder of the story: 

"October i8th, 1910. Notes made after 
arrival on board the Royal Mail S. S. Trent, 
made from memory and the log of the Trent's 
wireless operator. 

"Remained on watch until 3 A. M., i8th, 
listening to various stations working, static 
very bad. Unable to read Cape Cod but hear 
him working. I turned in at 3 A. M., but 
was awakened about an hour later by calls of a 
ship in sight. Descended into the lifeboat and 
called C Q D. Nothing doing. Then got an 
electric torch and commenced calling in Morse 
lamp fashion. Was eventually answered by 
the Trent and signalled him that we were in 
trouble and required help. Also conveyed to 
him that we were equipped with wireless. The 
Trent's operator was awakened, and he called 
us." 




Charles H. Huesgen from Underwood & Underwood 

"HEAVY ON THE STA'BOARD OAR" 

The staunch lifeboat of the America being pulled toward the rescue ship which was summoned by wireless. This was 

the first time in aeronautical or marine history that wireless had been used in this spectacular way. Thus ended 

the Wellman air voyage across the Atlantic after three days of struggle against great odds. Operator Irwin is wearing 

the straw hat and seated on the starboard side of the boat 



When the "America" Put Out to Sea 



323 



WHEN WIRELESS 
STEPPED IN TO RESCUE 

A> I had my head 
phones on all this 
time, I answered him 
and instant radio com- 
munication was estab- 
lished. 1 am indebted 
to Mr. Louis Ginsberg 
(the Trent's operator) 
for copies of the follow- 
ing messages which 
were copied and sent 
by him; I did not do 
so, merely reading out 
his messages to Mr. 
Wellman as he sent 
them. 

To the America Do you 
want our assistance? 

To the Trent Yes. Come 
at once, in distress, we 
are drifting, not under 
control. 

To the America What do 
you want us to do? 

To the Trent Come ahead 
full speed, but keep 
astern, we have a 
heavy tail dragging. 

To the America O.K. Am 
standing by wireless 
in case of trouble. 

To the Trent You will pick 
us up at daybreak, you 
will be better able to 
see us then. 

To the America O. K. 

To the Trent Come in 
close and put your 
bow under us, we will 
drop you a line but do 
not stop your ship as 
you will capsize us. 

To the America O. K. 

To the Trent Who are you 
and where bound? 

To the America S. S. Trent 
bound for New York. 

To the Trent Have one of 
your boats ready to 
launch, as we will prob- 
ably capsize when we 
launch our boat. 

To the America O. K. boat 
manned. 

To the Trent We are going 
to launch the boat, 
stand by to pick us up. 

Wireless communica- 
tion then ceased. I cut 



MARCONI WlfttU&SS TtLKCRAPH CO. OF AMERICA J\ 



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THE LOG OF THE AIRSHIP "AMERICA" 

A photograph of the last page of the log, which every radio operator must keep as a 
record of the transactions of the station. The call letters of the stations are in the 
left-hand column. R N R is the call of the English ship Trent, which rescued the 
America's crew of six. W was the call used by the airship. This is the first time this 
highly interesting document has been printed 



Radio Broadcast 



the antenna and ground wires, put the water- 
tight doors on the wireless cupboard, and stood 
by. The boat was successfully launched, a 
most hazardous operation. We were drifting 
fifteen miles an hour, with the boat swinging 
beam on to the sea and behind us the ton-and-a- 
half trailer. At the signal to "let go" both 
clutches holding the boat to the car were 
jerked. The boat fell into the water, lurched 
gunwale under, then righted. The trailing 
equilabrator hit us, stove a hole in the boat 
above the water line, and bruised Loud and 
myself. The Trent, ploughing along at 16 
knots, almost ran us down. We fell astern 
and waited for the steamer to come about and 
pick us up. After considerable maneuvering 
she came alongside, and with her derricks, 
lifted the lifeboat aboard. Thus was I able to 
save the entire wireless equipment. 

The America, with the weight of the lifeboat 
and crew released from it, shot up in the air 
several thousand feet and soon drifted out of 
sight. Before leaving her we opened the gas 
valves so that, eventually she would come down 
on the sea and not cause damage by landing 



or dragging over a city. We never heard of 
her again. 

Nobody but those who have experienced it, 
can imagine the feeling we had upon arriving 
on the Trent. W r e were overwhelmed with 
kindness. Two days later we arrived in New 
York where we found that our attempt to 
reach Europe in an airship had attracted ex- 
traordinary interest. We had occupied the 
front pages of the press of the world for several 
days. We failed, but in later years I had the 
gratification of knowing that other Americans 
accomplished what we had attempted and that 
the N C 4 "delivered the goods." One thing 
we had done. We had demonstrated that 
communication by radio from airships to the 
ground was easily accomplished and presented 
no great difficulties. While these pages were 
being written the press published the news 
that the Shenandoab, giant navy dirigible, had 
had one of her six engines removed in order 
to make a place for an additional radio equip- 
ment that would be powerful enough to reach 
shore from any position. This is, indeed, a 
tribute to the efficacy of radio in the air. 




CAPTAIN JACK IRWIN 

Preparing a "Knock-Out" receiver in RADIO BROADCAST'S laboratory for the RADIO BROADCAST COVERED WAGON, in which 
he is engaging in another radio adventure, as interesting in its way as the voyage of the America which he describes in 
this article. The Wagon will visit citfes and towns everywhere throughout the country, spreading the gospel of radio, 
and has already started on its way West. Arthur H. Lynch, editor of this magazine, is in the center and John B. 

Brennan, technical assistant, is at the extreme right 




Solving the Problems of the 
Neutrodyne 

One of. Professor Hazeltine's Aides Discusses the Set How to 
Neutralize Stray and Over-All Capacity in Two- and Three- 
Stage Radio-Frequency Sets A Radio Club of America Paper 




BY J. F. DREYER, JR. 

Engineer, Kazeltine Research Corporation 



A YEAR ago Professor Hazeltine des- 
cribed before the Radio Club of 
America his method of tuned radio- 
frequency amplification. The ob- 
jectionable and uncontrollable 
regeneration caused by the capacity which 
couples the grid and plate circuits of the 
vacuum tubes had previously stood in the way 
of a successful amplifier of this type. The 
receiver employing this method, which he called 
the Neutrodyne, removed this obstacle by 
neutralizing the objectionable coupling due to 
this capacity. Since that time the Neutrodyne 
receiver has become very popular; and many 
amateurs have constructed their own receivers, 
though often with much difficulty in com- 
pletely attaining the results of which a factory 
built Neutrodyne is capable. It is the purpose 
of the writer to describe the different problems 
which have presented themselves and to ex- 
plain how these problems were solved. 

1 n order to form a basis for further discussion, 
it is necessary again to explain the fundamental 
theory of capacity coupling neutralization. 
Fig. i illustrates a vacuum-tube amplifier whose 
grid and plate circuits are both tuned to the 
desired frequency. A passing radio wave 
causes a minute current to flow through the 
grid circuit CiLi. This circuit being tuned 
to the wave frequency, and thus having a high 
impedance, builds up an appreciable voltage 
which is impressed on the grid of the vacuum 
tube. By the relay action of the tube a similar 
current flows in the plate circuit. As this cir- 
cuit is also tuned to the wave frequency, it 
builds up a still higher voltage which is passed 
on to the next tube. Without neutralization, 
regeneration takes place due to the capacity 
coupling the grid and plate circuits. That is, 
the voltage built up in the plate circuit of the 
tube causes a current to flow through this 



capacity C 1 , which reinforces that already 
present in the grid circuit due to the passing 
wave. This may be sufficient to cause self- 
sustained oscillations which, unless very care- 
fully controlled, completely destroy the value 
of this form of amplification. 

HOW THE HAZELTINE PRINCIPLE IS APPLIED 

THE Hazeltine circuit as embodied in the 
Neutrodyne receiver eliminates this effect 
in the following way: A third coil, LJ is coupled 
closely to L2 as shown, so that one end (the 
other end being grounded) varies in potential 
in exactly opposite phase to that of the plate 
end of L2. A small condenser, Cn is then con- 
nected between this end of L$ and the grid of 
the tube. If C 1 , Cn, L2, and L3 are properly re- 
lated, the following action occurs: a current 
still flows through the plate-grid capacity, C 1 
due to the voltage built up in 1,2, but this cur- 
rent no longer enters the circuit CiLi for the 
reason that the combination CnL3 demands 
exactly the same current. This current there- 
fore, instead of flowing down through CiLi 
passes back harmlessly through CnL3 to its 
source at the plate of the tube. 




Cn 



FIG. I 
Circuit diagram illustrating the neutrodyne principle 



326 



Radio Broadcast 



The conventional Neutrodyne receiver em- 
ploys this circuit in a slightly modified form. 
There are usually four or five tubes employed, 
two radio-frequency amplifiers, detector, and 
two audio-frequency amplifiers. Or perhaps 
one audio tube is omitted and a radio tube used 
in place of it by the usual reflex method. The 
circuit of a five-tube receiver is illustrated in 
Fig. 2. Three separate rheostats are pro- 
vided, one for controlling the filament tem- 
perature of the radio-frequency tubes, one for 
the detector and one for the audio frequency. 
The radio-frequency rheostat provides a volume 
control for cutting down the strength of the 
signal, which is advisable when the user is lo- 
cated near one of the more powerful broad- 
casting stations. The other two rheostats are 
used in the ordinary way. 

The two radio-frequency amplifiers (em- 
ploying the Neutrodyne principle) are different 
from the one illustrated in Fig. i in that in- 
stead of tuning the plate circuit, a secondary 
coil closely coupled to the primary or plate coil 
is tuned. This allows a step-up ratio to be 
employed which gives greater amplification and 
selectivity. Also if the two coils are connected 
properly that is, with plate of one at the op- 
posite polarity to grid of the succeeding tube, 
then a portion of the secondary coil may be 
used in place of a third or neutralizing coil. 
Referring to Fig. 2, the neutralizing condenser 
Cn is connected from the grid of tube No. i to a 
tap on the secondary of the transformer unit B. 
The neutralizing condenser for the second tube 
is connected in a similar manner from the grid 
of that tube to a tap on the secondary of the 
unit C. The correct location of these taps de- 
pends on the value and range of the neutralizing 



condensers used that is, if the tap on coil B is 
moved up so as to include twice as many turns 
between it and the ground potential end of the 
secondary coil, then the capacity required at 
Cn will be only one half (approximately) as 
large as before. In this connection it should be 
pointed out that many receivers constructed 
from parts but which are not provided with a 
proper panel shield are very difficult to balance 
due to their inherent capacities. Referring 
again to Fig. 2, any capacity between adjacent 
grids tends to neutralize the tube capacity 
even more effectively than does capacity at Cn. 
This capacity will always be appreciable be- 
cause the fixed plates of the variable condensers 
Ci, C2, and C^ are connected directly to the 
grids of the tubes and therefore present large 
surfaces which act as the electrodes of con- 
densers connected between'them. As mentioned 
above, it is possible for these capacities to 
more than neutralize the tube capacities. If 
this is so, it is impossible, of course, to obtain a 
balance by a further addition of capacity at 
Cn. This condition may be eliminated by 
adding capacity at C 1 or better still by mini- 
mizing the inherent capacities by shielding. A 
grounded metal shield properly mounted on 
the panel cuts down the external field of the 
condensers sufficiently to make a balance pos- 
sible. 

ADJUSTING THE NEUTRALIZING CAPACITY 

THE actual adjustment of the capacity Cn 
is accomplished as follows: A strong signal 
either from a near-by broadcasting station or 
from a local oscillator is impressed on the an- 
tenna coil. The condensers Ci, C2, and C^ are 
then tuned to this signal with the filaments of 




FIG. 2 
Circuit of a five-tube Neutrodyne, showing the method of neutralizing the over-all capacity 



Solving the Problems of the Neutrodyne 



327 



all tubes lighted. At this time the receiver 
will probably oscillate. The filament of tube 
No. i is then extinguished, usually by placing 
a piece of paper under one of the filament prongs. 
The dials can then be retuned for maximum 
signal. This signal is present only because of 
the coupling between 
circuits A and B intro- 
duced by the grid- 
plate capacity in the 
tubes. If now the 
neutralizing condenser 
Cn is increased, the 
signal will grow weaker 
and weaker and finally 
will disappear entirely. 
If the capacity is still 
further increased, the 
signal will again be- 
come stronger. The 
circuit is then said to 
be over - neutralized. 
An over - neutralized 
receiver will oscillate 
when all tubes are 
operating. 

If the tube capacity 

is exactly balanced while the filament is not 
lighted and still cold, no signal will be trans- 
mitted through the succeeding tubes. The ex- 
planation of this is as follows: Referring to Fig. 
2, the voltage present in circuit A causes a cur- 
rent to flow through the grid-plate capacity of 
tube No. i , but at the same time another current 
flows through the neutralizing condenser Cn-i. 
These currents in passing through the primary 
and tapped portion of the secondary of circuit 

B, respectively, produce equal and opposite 
magnetic fields in circuit B which cancel out 
and produce no resultant voltage. 

A third neutralizing condenser is sometimes 
used for the purpose of neutralizing the very 
small capacity existing between circuits A and 

C. This will be discussed in detail later. It 
should be noted in Fig. 2 that primaries of the 
audio-frequency transformers are reversed re- 
lative to the secondaries in a manner similar 
to that employed in the radio-frequency cir- 
cuits. This very often prevents "singing or 
howling" at audio frequency. It might even 
be worth while for the purpose of improving 
the quality of reproduction to completely 
neutralize the audio-frequency tube capacities. 
This could be done by the introduction of very 
small capacities between adjacent grids. 



For Those Who Have Built Their Own 
and for Those Who Haven't 

This paper on the Neutrodyne receiver will 
have an appeal. As Mr. Dreyer, who is an 
assistant to Professor Hazeltine, the inventor 
of the Neutrodyne, says, "In one short year 
the Neutrodyne has sprung into very great 
general popularity." The many owners and 
operators of Neutrodyne sets should read this 
with great interest because it treats of kinks 
of operation and experiment with this type 
of receiver which have not appeared anywhere 
else. Those who have heard a great deal 
about the receiver and are a bit hazy on just 
how it works can easily bolster up their weak 
technical points by reading this paper. THE 
EDITOR 



HOW TO PREVENT REGENERATION 

IT IS necessary in a Neutrodyne more than 
merely to neutralize the tube capacities. I n 
the conventional type which employs three 
sharply tuned circuits it is necessary to remove 

all couplings that may 
exist between these 
circuits except mutu- 
ally conductive or one- 
way coupling of the 
tubes. I n fact if in any 
way radio - frequency 
energy may be trans- 
ferred from one circuit 
to a preceding one, re- 
generation will usually 
occur. This is always 
undesirable since it 
has the effect of sharp- 
ening thetuningto too 
great an extent and 
thus ruining the qual- 
ity of reproduction. 
The capacity coup- 
lings due to the tubes 
may be neutralized by 

the method already described. The other 
couplings which should be eliminated are: 

(i) inductive coupling between adjacent stages 
(coils Li-La, La-L3); (2) couplings from the second 
to the first stage due to the impedance of the leads 
to the B battery; (3) coupling from the third to the 
first and second stages due to improper connection 
of the telephone condenser; (4) coupling introduced 
by a common C battery or due to improper connec- 
tion of grid returns; (5) coupling between stages in- 
troduced by inductive loops in the wiring; (6) coup- 
ling between first and last stages due to inherent 
capacity between high-potential surfaces of these 
stages. 

The first of these, inductive coupling between 
coils of the different stages, may be eliminated 
by properly placing the coils. As is well 




FIG. 3 

How the angles of the coils used in the Neutrodyne re- 
ceiver may be used to give zero magnetic coupling 



328 



Radio Broadcast 




FIG. 4 

How coupling other than that due to tube capacity may be eliminated 



known, three coils may be placed mutually at 
right angles, so that the magnetic flux of any 
one has no resultant linkage with the turns of 
the others. A neater and more symmetrical 
arrangement was devised by Professor Hazeltine. 
He discovered mathematically that any number 
of coils might be placed on a common line of 
centers and if their axes were inclined at an 
angle of 54.7 degrees to this line of centers, no 
magnetic coupling would exist. That this is 
physically possible is rather hard to visualize at 
first. In Fig. 3 two coils are shown inclined at 
the theoretically correct angle. Magnetic flux 
of coil XY will pass through coil AB roughly as 
shown. Some of this flux, as represented by 
the middle line, passes through coil AB in a 
direction perpendicular to the axis of that coil 
and therefore does not link with the turns at 
all. Other portions of this magnetic flux will 
link with turns on AB. Some of it passes up 
and some down through the coil. There are, 
therefore, flux linkage in both senses. It seems 
reasonable that if the coils are set at some such 
angle as this, zero coupling may be obtained. 
This is true, but the angle varies slightly from 
the theoretically correct one, due to conditions 
not being ideal. The most conspicuous reason 
for variation is the fact that the leads which 
carry the coil current to the condenser form a 
single turn in an entirely different plane from 
the turns on the coil itself. The exact angle 
may be determined in any given receiver whose 
coils are first set approximately correctly as 
follows: the neutralizing condensers are first 
adjusted for a high broadcast frequency in the 
manner previously described. The settings of 
the two neutralizing condensers Cn-i and Cn-2, 



Fig. 2, are then noted and the pro- 
cess repeated at a low broadcast 
frequency. The settings will be in 
general different. This is due to the 
fact that, if inductive coupling is 
present between adjacent coils, the 
neutralizing condenser counteracts 
this as well as the coupling due to 
the tube capacities. This neutrali- 
zation will be exact for only one fre- 
quency, because with varying fre- 
quency the coupling effect due to 
the mutual inductance between coils 
varies at a different rate than the 
negative coupling effect due to the 
capacity Cn. If the settings are 
different, the coil angles are shifted a 
slight amount and the process re- 
peated. When the neutralization is correct at 
both high and low frequency ends of the scale, 
the coil angle is correct. It has been found to 
vary by this method from 54 to 58 in differ- 
ent receivers. 

INTER-CIRCUIT COUPLING IS OBJECTIONABLE 

/^VBJECTIONABLE coupling between cir- 
v_y cuits due to the use of a common C battery 
has proven very troublesome, but not unavoid- 
able if proper precautions are taken. The 
coupling introduced by the battery is analogous 
to that introduced in the theoretical circuit 
shown at the top of Fig. 4 by the impedance Z. 
Here the current of circuit CLi flows through 
the impedance Z which is common to circuit 
C2L2. It is evident that the current of one 
circuit will induce a voltage in the other, or it 
may be stated that if any portion of the current 
of one circuit flows through an impedance in 
common with any portion of the current of an- 
other, then these circuits will be coupled. The 
lower portion of Fig. 4 illustrates several ways 
in which this sort of coupling may be introduced 
(batteries, rheostats, and non-essential wiring 
are omitted to avoid confusing the figure) The 
plate circuits of tubes i and 2 carry radio- 
frequency currents which, like all other electric 
currents, must flow in closed paths. Let us 
trace the probable path of the radio-frequency 
current produced by tube No. i. Starting at 
the plate it passes through the primary of unit 
B and thence to the B battery, through the 
battery, and back to the filament, where the 
electron stream completes the circuit to the 
plate. If it does take this path, the batteries 
and, more important, the leads to the batteries, 



Solving the Problems of the Neutrodyne 



329 



form an impedance through which a similar 
current from tube No.. 2 must also flow. This 
common impedance introduces coupling. A 
large condenser placed as shown between the + 
B and the A leads has the effect of by-passing 
these currents and preventing their passage 
along common leads. To be effective, this 
condenser should be of at least o. i microfarad 
capacity. Also it should be carefully placed 
at the point which provides the minimum of 
common wiring for the currents in the separate 
circuits. It would be less effective if placed 
at the right, as shown by the dotted connec- 
tions. 

The detector plate circuit also carries radio- 
frequency current for which a reasonably low 
impedance path must be provided. If this 
path is not provided the signal will be con- 
siderably weakened. In regenerative circuits 
it is common practice to shunt the high imped- 
ances of the telephones or audio-frequency 
transformers by a condenser of about o.ooi 
microfarad capacity. This must also be done in 
the Neutrodyne, but care must be taken to 
connect this condenser from the plate of the 
detector directly to its filament. Otherwise if 
connected as shown alternatively in Fig. 4, a 
large radio-frequency current must pass through 
the B battery in order to complete its circuit. 
This might readily cause trouble. 

PREVENTING COUPLING PREVENTS OSCILLATION 

COUPLING sufficient to cause oscillation 
has been found when either a C battery 
or a common filament rheostat has been used 
to introduce a negative bias on the grids of the 
radio-frequency tubes. (See Fig. 4.) This is 
analogous to the coupling introduced by the 
common B battery, since the currents which 
pass through the grid filament capacities for 



the first two tubes must return to their starting 
points by way of this rheostat or C battery. 
If such a device is used, it should be by-passed 
with a large condenser which is located in the 
most desirable place, namely the one which pro- 
vides the least common wiring for the different 
currents. It has not been found necessary to 
use a bias on the radio-frequency tubes and 
therefore the grid returns are usually connected 
directly to the negative filaments of the sepa- 
rate tubes as illustrated in Fig. 2. 

Inductive loop^ in the low potential wiring 
cause a great deal of trouble and are present in 
a great many "home-made" receivers. If, 
for instance, the negative and positive battery 
leads are far apart, a loop closed at the ends 
by the filaments of the tubes is formed. This 
loop has mutual inductance to all coils in the 
receiver and provides a path for the feed-back 
of energy which is often sufficient to cause os- 
cillation. The remedy for this is obvious and 
simple. All wires which carry the B or A 
battery currents should be bunched together 
and thus minimize the area of possible loops. 

It was found in certain receivers that after 
all other possible sources of coupling had been 
eliminated that energy was fed back through 
the extremely small capacity usually present 
between circuits C and A. This capacity may 
be eliminated by shielding, but because this is 
expensive, several types of receivers have been 
equipped with a third arrangement which serves 
to neutralize this last form of coupling. The 
effect of this coupling capacity is only notice- 
able in receivers having very low resistance 
circuits and having therefore very high ampli- 
fication. It is accentuated by the presence in 
the neighborhood of the receiver of a piece of 
ungrounded metal such as a long piano hinge on 
the cabinet. Also, if the antenna is connected 




FIG. 5 

How the "segregated shielding" is used in a three-stage (radio-frequency) Neutrodyne 



330 



Radio Broadcast 



in such a way that it passes behind the receiver 
close to the last circuit, the effective capacity 
between the first and last circuits is increased. 
The antenna lead may be shielded with a 
grounded metal tube or Belden braid, and the 
metal hinge may also be grounded. If these 
precautions fail to remove the trouble, complete 
shielding or neutralization must be resorted to. 
Neutralization of over-all capacity may be 
accomplished with the arrangement of Fig. 2 
already referred to. When adjusted, the action 
is as follows: a very small current passes 
through the space from the high potential parts 
of circuit C to circuit A. However, another 
larger current flows through the third neutraliz- 
ing condenser Cn-O. This current, in passing 
through the extra coil Lo which is coupled 
closely to Li, produces a magnetic effect in 
circuit A exactly equal and opposite to that 
produced by the first current in flowing through 




Li. The net regenerative effect is then zero. 
It is interesting to note the relative size of the 
coils and capacities involved in this action. In 
a certain receiver Li, L2, and L3 are of 65 
turns each. A tap on L3 used for two neutral- 
izing condensers is located 8 turns distant from 
the grounded side of that coil. Lo has but one 
turn. The neutralizing condenser Cn-O is of 
the usual form and when adjusted has a capac- 
ity of about 10 micro-microfarads. 

The adjustment of this third neutralizing 
condenser is accomplished by first encouraging 
the receiver to oscillate. This is done by tuning 
the circuits to the highest possible frequency 
and by adjusting the plate and filament voltages 
to produce the greatest amplification. If the 
receiver oscillates under these conditions, the 
condenser Cn-O is increased until oscillation 
ceases. If increased too far oscillation will again 
commence. The correct setting of this over- 
all condenser is, of course, at the center of the 
range of non-oscillation. If no oscillation or 
regeneration is noticeable when these steps are 
taken, over-all neutralization is unnecessary 
and may be omitted. 

Another cause of unsatisfactory operation 
on the part of Neutrodyne receivers is that in- 
troduced by local conditions. High impedance 
ground leads may be the cause of oscillation 
for reasons which are not very clear. The 
trouble may usually be eliminated by replacing 
the long lead with a short one to the nearest 
piping system, such as the radiator or water 
pipe. If the A battery is located at some dis- 
tance from the receiver and is wired to it with 
long leads, trouble again may occur. This 
form of oscillation trouble usually appears over 
only a limited frequency range and is probably 
due to an action which occurs at the natural 
period of the ground or battery system. 



THREE-STAGE NEUTRODYNE RECEIVERS 
THEIR PROBLEMS 



AND 



FIG. 6 

An experimental three-stage Neutrodyne 



SO FAR, all discussion has been limited to 
the two-stage receiver. Successful three- 
stage Neutrodyne receivers have been con- 
structed and when finally adjusted give very 
great amplification and selectivity. One of 
these constructed by H. W. Dreyer and the 
writer and used with a ten-foot indoor antenna 
compared favorably with the performance of 
a good two-stage receiver when used with an 
outdoor antenna 75 feet long. 

The problems which arose in the construction 
of this receiver were of the same nature as 



Solving the Problems of the Neutrodyne 



those previously 
discussed. They 
are, however, more 
difficult to solve, 
and the stray coup- 
ling had to be elim- 
inated to an even 
greater degree than 
was necessary with 
the two-stage. Fig. 
5 illustrates sche- 
matically some of 
these problems. 

It should be noted 
that three separate 
by-pass condensers 
are used to prevent 
B battery coupling. 
The most trouble- 
some coupling, 
however, was found 
to be that due to 
over-all capacity. 
This becomes of 
more and more im- 
portance as the am- 
p 1 i f i cation i n - 

creases. When four tuned circuits are used, it 
becomes too cumbersome to effect a neutraliza- 
tion of all capacity couplings between circuits. 
Since to eliminate them would require six ad- 
justments, it was decided to shield out as much 
as possible of these capacities and neutralize 
the remaining tube capacity by the Hazeltine 
method. The shielding of a copper lined 
cabinet proved ineffective, due probably to 
eddy currents set up in the shield. These cur- 
rents caused coupling between first and last 
stages in a manner similar to that caused by 
inductive loops in the wiring. 

Shielding in the form of a cabinet lined with 
copper wire grids did prove effective. Care was 
taken to see that no closed loops were formed 




Top view of a 
Note the wire 



FIG. 7 

three-stage (radio-frequency) Neutrodyne. 
shielding in the bottom of the cabinet 

in this shielding. Also it was necessary to segre- 
gate it into four insulated portions adjacent to 
the four coil systems. These four sections 
were grounded at the low-potential points of the 
individual coil systems. Of course, no attempt 
was made to shield the magnetic fields, but 
these are not harmful if the coils are at the 
proper angle. 

In the short year that the Neutrodyne circuit 
has been before the public it has met with 
very great popular approval. In the coming 
year improvements will undoubtedly be made, 
but probably not of a radical nature. Greater 
amplification may be expected by more care- 
ful construction and by the use of more 
shielding. 



/I J. HAYNES has written an interesting and informative article about 
-/JL . the super-heterodyne and why high frequencies should be used in the 
intermediate-frequency amplifier, a subject which has received very little attention. 
The article will help any experimenter who is building a super-heterodyne and 
will aid and interest those who already own a receiver of this type; it will be 
printed in an early number. 



a =y<^ -^*<ap>-^ 

'Che Listeners' Point of" 

(*ondu(Fle,d by eJ^ennic Irene TIlix 
Are Women Undesirable Over the Radio? 



A'ER having written for the June 
number of this department a nice 
little comment regarding women 
announcers, and one such an- 
nouncer in particular, came the dis- 
covery, when this same number was published, 
of a letter in the department, "What Our 
Readers Write Us," denouncing all women 
announcers because, the voice of a woman 
when she cannot be seen "is very undesirable, 
and to many, both men and women, displeas- 
ing." 

The man responsible for this opinion bases it 
on his experience with the sales of phonograph 
records. . Various manufacturers lost several 
thousands of dollars, he tells us, before they 
learned that the public will not pay money to 
listen to the talking record of a woman's voice. 

This is interesting. And when one stops to 
consider the matter it is impossible to recall a 
phonograph record of a monologue by a woman. 
Yet some of the highest paid women in vaude- 
ville are the women heard only in monologues. 

Does this mean that when a woman is speak- 
ing she may be fascinating as long as she re- 
mains in sight, and becomes displeasing the 
moment she cannot be seen although she may 
go right on talking just as delightfully as the 
moment before? That is exactly what it means 
provided the experience of the phonograph men 
is all the evidence needed to prove so radical a 
statement. But is it logical to draw final con- 
clusions regarding so important a matter from 
but one medium of experiment? It scarcely 
seems so. 

In its fundamentals the question is one for 
the psychologists to deal with. Perhaps, now 
that the radio is bringing women daily before 
the microphone, psychologists will delve into 
this subject and, if their conclusions agree with 



that of the phonograph dealers, we shall then 
know the cause for this strange difference in the 
effect produced in the opinion of some be- 
tween the voices of men and women when the 
speakers are invisible. 

It would be interesting to know how the 
radio public feels about this matter. Let us, for 
instance, take station WOR at Newark. Many 
women speakers have been presented from this 
station, women of notable achievement in 
various avenues of activity, with the majority 
drawn from the dramatic profession. 

Surely, if a woman's voice is both displeasing 
and undesirable over the microphone, WOR 
must have received complaints along this line 
from many of those who regularly tune-in on 
this station. Any report from there would be 
something of a test because no other station in 
the country has presented so many women in 
speeches and monologues as has WOR. 

Then there is WGY at Schenectady, where 
scarcely a week passes without the presentation 
of a radio drama with women in the cast. Do 
the unseen audiences experience a feeling of re- 
pulsion every time Rosaline Greene or Lola 
Summers, Marie Prott, Charlotte Paulos, 
Mildred Stanyon, Gemma Votties, or others 
among the women in this dramatic company, 
speak? If this were true, then WGY would 
have received so many objections to presenting 
women before the microphone that plays em- 
ploying both men and women would long since 
have been discontinued. Which would mean 
the discontinuance of all their drama programs, 
for no one of any sensibility could listen to a 
radio play given entirely by men. 

We are willing to grant that were the profession 
of broadcast announcing to be equally divided 
between men and women the honors would 
without question go to the men. But this 




ETHYL HAYDEN 

This young lyric soprano, favorite among large numbers of concertgoers, recently gave pleasure to many thousands of 
unseen listeners when she sang the role of Marguerite in the concert performance of " Faust," given atMankato, Minn., 

and broadcast through WLAG 



334 



Radio Broadcast 



does not prove that all men are successful as 
announcers and all women unsuccessful. 

Women, as a rule, when they speak over the 
microphone, are apt to make one of two mis- 
takes. They either speak in a patronizing 
tone or they are precise to a point of exaspera- 
tion. With the latter, it is as if they stopped 
to cross every T and dot every I . The effect in 
either case is disagreeable. And, so far as the 
present writer's experience goes, women radio 
speakers are lacking in humor. On the other 
hand, men are inclined to be preachy. Here 
is a choice of two evils, one as bad as the other. 
But there are some men heard via radio to 
whom it is joy unalloyed to listen. 

There are a few announcers in this country 
all men who are beyond criticism. They are 
consequently an unfailing pleasure to hear, 
from their first greeting to their final, "good 
night." They know just how far to carry 
familiarity in their speech a trait that is the 



final test of an announcer's adaptability to his 
position. The men who are continually "jolly- 
ing" their listeners, trying themselves to be en- 
tertainers, become extremely tiresome. A little 
of this sort of thing may be agreeable and effec- 
tive, but more than a little becomes a surfeit. 
This is not an individual opinion, but one that 
has been expressed by large numbers of people. 

If Mr. Henry Ford ever loses his job as a 
maker of automobiles he could undoubtedly 
get a position as announcer without half trying. 
This was proved when, at the close of the recent 
automobile race at Indianapolis, he was lured 
to the microphone by the genial Mr. Kaney 
who, for five hours, had himself been at the 
microphohone announcing the progress of the 
race which was broadcast by WDAP and WGN, 
Chicago. 

Although Mr. Ford had been busy for many 
hours in his capacity as referee, his voice came 
through the air as fresh and vigorous as if 




Apeda, New York 

PAUL SPECHT'S FAMOUS ALAMAC ORCHESTRA 

Just as you sometimes "cannot see the forest for the trees," so you sometimes cannot see a jazz orchestra for the instru- 
ments. There are eleven men in this Alamac orchestra, and, without including those manipulated by the man 
at the drum, there are about two dozen instruments in the picture. To the drummer can easily be credited half a 
dozen more. An average of three instruments, let us say, to a man. But while some are accountable for only one 
instrument, others handle two three four or five. Yet when you hear them via radio, which it is your privilege to do 
twice a week through station W J Z, the orchestra plays with a smoothness which gives no indication that any of the men 
change from one instrument to another during a performance 



The Listeners' Point of View 



335 



fatigue were something unknown to him. It 
was a perfectly poised, finely modulated, clear 
cut voice that would have held the attention 
even had the speaker been unknown. And 
Mr. Ford said in a few seconds as much as some 
radio speakers would have taken five minutes 
to say, and without saying it as well, at that. 

But, according to our phonograph authority, 
if the most famous woman living had been at 
that race and had been persuaded by Mr. 
Kaney to speak over the microphone, all who 
heard her would have found the experience dis- 
pleasing. 

How do you feel about this question, my 
readers? 

Program Director Musician Woman 

WHATEVER may be said as a gen- 
eralization regarding women an- 
nouncers, Mrs. Eleanor Poehler, 
director and chief announcer at station WLAG, 
has been sufficiently successful in her work to 
bring her many assurances of commendation 
from radio fans, near and far. 

Mrs. Poehler is a musician of broad educa- 
tion and experience. Left a widow a year 
after her marriage, she turned her attention to 
the cultivation of her voice, having the good 
fortune to study with the internationally known 
teacher, Mme. Schoen-Rene, who was then a 
resident of Minneapolis. There followed a 
period of study in Europe. Upon her return 
to this country Mrs. Poehler was occupied with 
concertizing and teaching. Then came another 
period of study abroad, this time chiefly in 
England. The breaking out of the War forced 
a return home. 

" I have carried on ever since," said Mrs. 
Poehler when asked to tell further details of her 
career. "When the position of program di- 
rector at WLAG was offered me, I was given 
but twelve hours to reach a decision. 1 have 
been glad ever since that I had so little time to 
consider the matter, because I took a flying leap 
in the dark and have loved the work better than 
anything else I have ever done. I am still sing- 
ing and expect to continue doing so for a num- 
ber of years to come. I have lost my fairness, 
am trying to keep away from fatness, but can- 
not possibly avoid fortyness." 

Mrs. Poehler has for many years taken active 
interest in musical educational work in Min- 
nesota and the Dakotas. It was she who first 
made a special study of radio voices, and 




Mishkin, New York 
FREDA BENNECHE 

Born in New York, the daughter of Edward Benneche 
who, for years, was president of the Arion Society and 
prominent in other musical circles, Miss Benneche, color- 
atura soprano, came naturally by her musical gifts. She 
was recently heard by radio through station WOR 

through tests proved that many voices of good 
quality that are too small of volume for the 
public concert stage, are admirably adapted for 
radio performance because of the increased 
volume made possible through amplification. 
She has created several popular radio stars in 
the Northwest since she took over WLAG. 
Any one listening in regularly to her programs 
can readily see that she is not carrying on her 
radio work simply for the purpose of "giving 
the public what it wants," but rather with the 
idea of affording the radio public opportunities 
to hear a sufficient amount of good music to 
gratify those who already appreciate it, and 
to create a taste for it among those who, 
hitherto, have listened to little but trash. 

Good Programs from Here and There 

THE last concert for the season given by 
the Mendelssohn Glee Club of Albany, 
with Mary Jordan, contralto, as assisting 
soloist, and broadcast through station WGY, 



336 



Radio Broadcast 




Underwood & Underwood 
WILLIAM VAN HOOGSTRATEN 

Joint conductor with Willem Mengelberg of the New York 
Philharmonic orchestra which was frequently heard by 
radio audiences during the last season through station 
WEAF. Mr. Hoogstraten is this summer chief con- 
ductor of the concerts being given by the Philharmonic 
orchestra every night at the Lewisohn Stadium, the 
College of the City of New York 

provided an agreeable evening for listeners-in. 
The Russel Sage College Glee Club heard 
through WHAZ was another excellent feature. 
The Girls' Glee Club of the Davenport, Iowa, 
High Schools and the combined quartets from 
the Junior High Schools of the same city were 
enjoyed through WOC. And the Advanced 
Elementary School Orchestras of St. Louis, 
heard through KSD, gave a public concert 
sufficiently well-done to hold the attention 
throughout the entire performance. 

A Radio Singer Advances 

HERE'S wishing Miss O'Brien of Kansas 
City the best of success in her future 
musical work! 

Miss O'Brien, who has a brilliant full soprano 
voice, far superior to the majority of voices 
heard over the radio, has frequently sung at 
station WHB, Kansas City. Not long ago 
she gave her farewell program preceded by the 
announcement that she was going East to study 



with the view of furthering her career. Her 
singing seems to justify her ambition to develop 
her work to the fullest possible extent. Every 
venture to become a widely known professional 
in the musical world these days when com- 
petition is so keen, is a big risk, and that is why 
one admires those who make the venture when, 
as in the case of this young soprano heard by 
radio, there is sufficient natural gift to justify 
ambition. 

So again here's wishing Miss O'Brien of 
Kansas City the best of success ! 

What Are the Elite Radio Orchestras? 

HOW many orchestras heard regularly 
over the radio make it a custom to 
give occasional programs composed 
wholly of standard musical works? By stand- 
ard musical works is meant works that have 
been accepted by the musical world as worthy 
of performance on orchestral programs con- 
stantly given through the regular concert 
channels. This eliminates all jazz and the 
ephemeral popular music that is here to-day 
and gone to-morrow. 

Note that the question is not how many 
orchestras heard over the radio always give 




Zintsmaster, Minneapol 
MRS. ELEANOR POEHLER 
Director and Chief Announcer of sta- 
tion WLAG, St. Paul Minneapolis 



The Listeners' Point of View 



337 



programs of standard works, but how many 
even occasionally give such programs? 

The conductor of this department greatly 
desires full statistics regarding this matter. 
She at present has but a very small number of 
such orchestras on her list. 

Who will help make this list complete by 
sending in the name or names of any radio 
orchestras known to be in this class? In- 
dividual credit for all such information will be 
duly given in this de- 
partment. 

The Girl Scouts at 
Chicago 

ALTHOUGH it is 
not unusual for 
some broadcast 
stations to put on pro- 
grams given wholly by 
girl scouts, the first 
time, so far as can be 
learned, that the camp 
song, " Innisfree," was 
heard by radio was dur- 
ing the recent annual 
National Convention of 
Girl Scouts held at 
Chicago when this song, 
which was the official 
song of the convention, 
was broadcast from sta- 
tion W DA P, now WGN . 
The singer was Elsa 
Clement, Field Captain 
and Captain of Troop 
26, Toledo Girl Scouts. 

From reports that came in later, girl scouts 
all over the country listened with delight to 
this song which they all love, although it is far 
from being either ragtime or jazztime. The 
poem by William B. Yeats has become a classic 
while he is still living. It was set to music by 
an Englishman and is the official song of the 
English Girl Guides. Do you recall the poem? 
It begins: 

I will arise and go now 

And go to Innisfree 

And a small cabin build there 

Of clay and wattles made. 

Nine bean rows will I have there 

A hive for the honey bee 

And live alone in the bee-loud glade. 

And the last stanza, what an appeal it makes 
to many city-bound folks at this time of year! 




ELSA CLEMENT 

Who, during the National Convention of Girl Scouts in 

Chicago, broadcast the official song of the convention 

from station W D A P (now WGN) 



I will arise and go now 
For always, night and day, 
I hear lake water lapping 
With low sounds by the shore. 
While I stand on the roadway 
Or on the pavements gray, 
I hear it in the deep heart's core. 

A mile distant from Camp Andree Clark, 
Briarcliff Manor, N. Y., the largest national 
girl scouts' camp in the country, there is a log 
cabin where different 
groups of girls are sent, 
from time to time, to 
live the primitive life, 
without even cooking 
utensils or beds, being 
dependent wholly on 
their own efforts to get 
along. It is called 
"Innisfree," and the 
girls not only enjoy 
the cabin and seek the 
privilege of staying 
there, but they like its 
name because they like 
the poem and song. 

Such is the romantic 
atmosphere surround- 
ing the song that went 
out over the air to thou- 
sands of listeners from 
station WDAP in the 
great city of Chicago 
where the atmosphere is 
so alien to that pictured 
in " Innisfree." 



Livingston 




Good Radio Music from Mankato, Minn. 

OT long ago, upon tuning-in this station, 
WLAG, came the announcement that a 
concert performance of "Faust" was 
about to be broadcast from Mankato, Minn. 
That settled it, so far as one listener was con- 
cerned. The evening would be spent enjoying 
this performance. The fact that it was given 
at Mankato meant that it would be well worth 
the hearing. For Mankato is one of the most 
musical towns in the entire country, a place 
where every artist, even the greatest, is happy 
to get a chance to appear. At the end of each 
season Mankato can show you a list of musical 
attractions presented that would make a similar 
list in many a good sized city seem indifferent 
in both quantity and quality. 



338 



Radio Broadcast 



During that performance of "Faust" there 
came to the listener, many hundreds of miles 
distant, a voice singing the role of Margue- 
rite that held the attention throughout the 
evening, a voice of lovely quality and used with 
skill. It was later learned that the singer was no 
other than Ethyl Hayden, one of the foremost 
among the young lyric sopranos of the day. 

When the radio can carry a voice many 
hundreds of miles 
with such fidelity 
that its quality 
and manner of pro- 
duction are un- 
mistakable, it is a 
wonder that any 
manager stands in 
his own light by not 
permitting his ar- 
tists to be heard, 
occasionally at 
least, through this 
medium. Hearing 
that singing by 
Ethyl Hayden was 
more convincing 
as proof of the 
quality of her work 
than would have 
been the perusal of 
a whole book of 
press notices about 
her. 

Others in this 
cast who were 
heard to excellent 
advantage were 
Agnes Snyder in the 
double r61e of Siebel 
and Martha; Louis 
Klebba as Faust ; 
Rollin Pease, Me- 
phistopheles, and 
Glen Shoemaker as 
Valentine. The 
choruses were car- 
ried off with telling effect by the Women's 
Glee Club and the Orpheus Club of Mankato, 
while the orchestra was a combination of the 
Mankato Festival orchestra and members of 
the Minneapolis Symphony. The entire pro- 
duction was directed by Mrs. H. A. Patterson 
with a vitality and flexibility that aroused 
unstinted admiration. 

This performance was part of a spring festival 



I 




WADE HINSHAW 

This is the man who led the "Radio Sing" at station WJZ. He 
was not so very long ago a grand opera singer, but during the 
last few seasons he has devoted his time to presenting the classic 
comedies of Mozart in tabloid form throughout the country with 
great success. Mr. Hinshaw's achievements in this line have done 
much to further the cause of Mozart among many who hitherto 



given at Mankato, and to WLAG should go a 
vote of appreciation from radio fans for making 
possible an opportunity to hear it. 

Excellent Polish National Music fromWGY 

T WILL be a long time before some of us 
who heard it, will forget the singing of 
Chopin's " Hymn to Polish Song," by the 
two Polish societies, the Kalina Glee Club and 

the Liberty Bell 
Chorus of Amster- 
dam, N. Y., and 
broadcast from 
Station WGY at 
Schenectady. I t 
brought to a close a 
program composed, 
with but one or two 
exceptions, of 
Polish music sung 
by Polish singers in 
the vernacular. The 
way in which they 
interpreted this 
music was proof 
that, no matter how 
long they may have 
lived in this country, 
even if born here, 
thespiritofthe land 
of their fathers 
animates them. 

The fact that the 
program was not 
interrupted by a 
speech totally for- 
eign to the subject 
of music added im- 
measurably to its 
enjoyment. Abom- 
inable custom 
that of injecting 
speeches into the 
programs of radio 



White, New York 



seldom had an opportunity to hear operatic music 



concerts ! 



M 



ANY interesting talks are heard over the 
radio, but more often they are only 
partially heard, because they are almost always 
too long. Many listeners tune-out before the 
end is reached. When it seems as if the talk had 
continued for at least half an hour, the watch 
will show that it has been going on but fifteen 
minutes. Which proves that it should have 
stopped at the end of ten minutes. 




HOW TO REBUILD A RADAK C-3 INTO A REFLEX RECEIVER 



FIGURES i, 2, 3, and 4 tell the story 
of how the Radak and similar re- 
generative receivers can be made 
over into a more efficient and de- 
sirable reflex set plus one stage of 
external audio amplification. The Radak -3 
is a single-circuit receiver manufactured by 
the Clapp-Eastham Company, designed to 
cover wavelengths between two hundred and 
two thousand meters, and includes a two step 
audio-frequency amplifier. It is an excellent 
receiver of its type. Radio progress and the ap- 
preciation of the interference caused by single- 
circuit regenerators have relegated it with 
antiquated and ostracized apparatus. 

The Radak C-3 (as well as other receivers of 
this type but of different manufacture) are 
mechanically characterized by three predomi- 
nant parts, a tuning coil, a rotating tickler and 
a variable condenser (plus, of course, two 
stages of audio- 
amplification). In the 
case of the Radak, 
there are two variable 
condensers, one for 
short waves and one 
for long waves. Single- 
circuit receivers, and 
how to recognize them, 
have been discussed at 
greater length in " The 
Truth About Trick 
Circuits " appearing 
in the March, 1924, 
issue of RADIO BROAD- 
CAST. 



What the Lab Offers You This Month 



How to rebuild your single-circuit Radak 
receiver into a reflex set. 

Variations in building the "Knock-Out" 
four-tube receiver, using Sickles coils for the 
inductances and Daven resistors. 
Some recommeded resistances for use in 
re si stance- coupled audio amplifier circuits. 
Installing a reconnected A battery rectifier 
for charging B batteries. 
How to make very efficient home-made in- 
ductances. 

Suggestions for adding to the home labor- 
atory. 



Sets of this type can be salvaged and made 
over into very efficient non-radiating reflex 
receivers at a cost that is nominal compared 
with the expense of totally new equipment. 

THE ADDITIONAL PARTS 

THE following extras are required for the 
reconstruction of the Radak and similar 
receivers : 

Radio-Frequency Transformers, Ti and T2, 
at $3.00 $6.00 

One variable condenser, .00035 m fd. (17 

plate) 4.00 

One Celerundum Crystal Detector . . . 1.25 

Full details concerning the various possi- 
bilities for the radio transformers Ti and T2 
will be found in "The R. B. Lab" for the cur- 
rent and last three issues of RADIO BROADCAST, 
as well as in articles, "A Knock-Out One- 
Tube Receiver" and 
a " Knock-Out Four- 
Tube Receiver" ap- 
pearing respectively in 
the April and June 
numbers. 



PREPARING THE 
RADAK 

THE first step in 
this rejuvenation 
is the dismantling of 
the tuning inductance, 
fixed condensers, and 
the complete unwiring 
of the tuningelements. 



340 



Radio Broadcast 



All connections are removed from the de- 
tector jack, and likewise from the binding-posts 
excepting plus B and plus and minus A. The 
first amplifying transformer is completely dis- 
connected and the four leads permitted to hang 
freely. 

The grid and plate connections to tube num- 
ber two are removed, as well as the connec- 
tion to the prong marked A of the middle jack 
(the left hand jack in Fig. i). The original 
detector socket and detector jack are not used 
on the finished reflex set, tube number one 
being plugged in the middle socket and con- 
trolled by the middle jack (originally the first 
step jack). 

The tuning coil is removed by unscrewing the 
two screws above and below the tickler dial, 
and the set screw on the shaft behind the panel. 
Clip the leads to the taps close to the panel. 
The circular fixed condenser is also demounted 
by removing the holding screws through the 
panel, which, on rebuilding the set, are used to 
hold the celerundum fixed crystal detector. 

The front of the panel is left unaltered, the 
vernier dials and all controls, excepting the in- 
ductance switch and the detector rheostat, 
being used in the reconstructed receiver. 




FIG. 2 

The Radak -3. All controls excepting the inductance 
switch, the detector jack and the detector rheostat are 
used in the completed reflex 

REBUILDING 

THE first task in reconstructing is to mount 
condenser C i and transformer Ti in place 
of the dethroned tickler and tuner. As the 
vernier dial is fitted for an eighth inch shaft, 
it will be necessary to file or turn down the 
usual one quarter inch shaft on the condenser. 
This is easily accomplished using a flat file 
with the aid of a vise. File the shaft square, 
then hexagonal and finally round. This will 




FIG. i 
The circuit for the rebuilt Radak. The reflex is a great improvement over the former single-circuit regenerator 



In the R. B. Lab 



OCT. 



generally achieve the desired reduc- 
tion. It is probable that the shaft 
will also have to be shortened by 
about three quarters of an inch. 

The condenser is then mounted on 
a 4!" by 3" piece of f " wood by 
means of the usual screws. A \" 
hole should be allowed for the shaft, 
through which the collar of the knob 
and dial may pass. A half inch slot 
is sawed from the outer edge to the 
center hole to permit the entrance of 
a screw-driver for tightening the set- 
screw. The condenser may now be 
mounted by means of the original 
screws passing through the panel, 
and Ti fastened to it with brackets. 
Fig. 3 illustrates this arrangement 
very clearly. 

T2 is mounted on the small condenser, 
marked "low wave," which capacity is 
shunted, as a vernier, across the large 43 plate 
affair, C2. 

The crystal detector is secured to the panel, 
as before mentioned, by means of the screws 
which originally provided the terminals to the 
circular fixed condenser. The middle screw 
is brought through the panel and tightened 
"blind" merely to hide the hole. 

HOOKING UP THE "NEW" SET 

THE circuit is shown in Fig. i, and our old 
readers will recognize it as the justly famous 
single-tube reflex receiver plus one stage of ex- 
ternal audio-frequency amplification. 

Only two points in the wiring should bother 
the experimenter the connections to the first 
amplifying transformer, T3, and those to the 





FIG. 4 

Rear view of the rebuilt Radak. The de- 
tector jack, rheostat, and socket are not used 



FIG. 3 

Mounting the detector and condenser Ci without boring new holes 



external amplifier. Even these obstacles are 
more imaginary than real. 

If the secondary leads from T3 are examined, 
one will be found on the surface of the winding 
and the other a half inch or so nearer to the core. 
The inner wire is the filament connection (F) 
and the outer should be led to the grid (G). 

To complete the plate circuit to the first 
tube, it is merely necessary to run the plate 
to the primary of T2, and from T2 to point A 
of the middle jack. The plus B battery is al- 
ready wired from the binding-post to the jack, 
as well as are the filament connections for 
automatic control. 

OPERATION 

THE operation of the completed receiver 
is quite simple, and is that happy charac- 
teristic of the single-tube reflex. Almost all 
tuning is accomplished with Ci (the 
lower left dial), and C2 merely used 
to increase selectivity. The vernier, 
03 will rarely if ever be touched. 

As there is no bias whatever on the 
amplifying tube, such as is generally 
secured across a rheostat in the 
negative filament lead, it is probable 
that the amplifier will distort ap- 
preciably. This may be remedied 
by including a bias (C) battery, 
of three to six volts, in the grid 
circuit, negative to the grid. In 
the receiver described, the C bat- 
tery is most conveniently placed 
as suggested by the dotted lines 
at B. 



342 



Radio Broadcast 




FIG. 5 

Behind the scenes. Reflex and three stages of resistance-coupled amplification. The com- 
pactness and neatness are facilitated by the "Resisto-Couplers" between the sockets 



The rebuilt Radak will give excellent loud- 
speaker volume on all local and many distant 
stations. The single tube alone will actuate 
the loudspeaker on locals. The set is quite 
selective, does not radiate or oscillate, and is 
very stable and easily operated. 

ANOTHER FOUR-TUBE KNOCK-OUT 

A SUBSEQUENT model of the receiver 
described by Zeh Bouck in the June 
RADIO BROADCAST is shown in photo- 
graph 5. This later design differs in several 



ways from the original receiver, and repre- 
sents improvements that will appeal to our 
many readers who have followed the "knock- 
out" series. 

The panel layout has been altered slightly, 
the rheostats being raised one inch above the 
center of the panel. This balances the ar- 
rangement, and adds subtly to the aristocratic 
simplicity of the receiver. 

The Sickles "Diamond Weave Transformer 
Coils" have been substituted for the rewound 
neutroformer type inductances. The Sickles 
coils are easily mounted on any type variable 




FIG. 7 

A highly efficient form of inductance 



FIG. 6 

The A battery rectifier permanently mounted on the sta- 
tion wall, and wired for charging both A and B batteries 



In the R. B. Lab. 



343 



condenser. In most cases this is best accom- 
plished by removing one of the machine screws 
from the condenser end plate (generally a six 
thirty-two) and substituting a longer and head- 
less screw which will take the threaded support 
on the coil. 

The very compact construction of the set is 
made possible by the use of " Resisto-Couplers " 
(Daven Radio Company), in the three-stage 
resistance-coupled amplifier. The Resisto- 
Coupler clips the coupling resistance, grid leak, 
and isolating condenser into a small unit which 
fits nicely between the tubes and under the 
jacks A five inch base-board was used. 

The circuit is identical with that described 
in Mr. Bouck's original article, except that the 
.00025 m fd. stabilizing condenser is more effec- 
tive between the grids of the first two amplify- 
ing tubes (not counting the reflex tube), rather 
than between grids one and three. 

OTHER COUPLING RESISTANCES 

SINCE the article on resistance-coupled 
audio amplification, by G. Y. Allen, 
in the May RADIO BROADCAST, several 
manufacturers have appreciated the possi- 



bilities of this system, and several new resis- 
tors, suitable for coupling resistances, have 
been placed on the market. Any of the follow- 
ing are now easily obtainable and are equally 
efficient : 

The Bradley-Ohm. 

The Daven Resistors (fitting the Resisto-Coupler). 

The Lavite. 

The Ward-Leonard non-inductive resistances. 

AN A BATTERY RECTIFIER PERMAN- 
ENTLY INSTALLED FOR CHARGING B 
BATTERIES 

THE vibrating rectifier described in the 
B battery charging article in last 
month's RADIO BROADCAST is shown per- 
manently and conveniently mounted in pho- 
tograph 6. This makes a very business-like 
installation. The rectifier, lamp, and terminals 
are mounted as a single unit, and wired to the 
battery and to the station switch-board from 
which the rectifier is controlled. Binding- 
posts are also provided for connection to bat- 
teries other than the cells permanently wired. 
Three posts are provided, one positive, for 




FIG. 8 

A receiver built by Mr. Brown, using his corrugated pasteboard inductances 



344 



Radio Broadcast 




FIG. 9 

A spider-web variocoupler. Unusual, and per- 
haps a little more efficient than the ordinary 

both A and B batteries, and two negatives, 
one for A and the other for B. The use of a 
common plus post, which runs to the ammeter 
on the front of the rectifier, makes it possible 
to employ this meter in both A and B battery 
circuits. 

HOME MADE ULTRA EFFICIENT IN- 
DUCTANCES 

PHOTOGRAPHS 7, 8, and 9 show the 
highly efficient inductances made by 
one of our readers, Mr. C. H. Brown. 
Theoretically, the most efficient inductance 
would probably be a coil of self-supporting bare 
wire wound on air. The dielectric losses and 
distributed capacity of this coil would be re- 
duced to a minimum. However, such induc- 
tances are hardly practical, and the nearest 
approach to this theoretic ideal is found in 
honeycombs, spider-webs, and the coils wound 
by Mr. Brown. 

The winding form in Fig. 7 was made from the 
common corrugated pasteboard used in pack- 
ing photographs and for making heavy paste- 
board boxes. A strip of the material, cut to 
the desired width, is merely bent backward 
into a tube, and fastened with glue or eyelets. 

Fig. 9 shows a spider-web variocoupler that 
will appeal to our less conventional readers. 
The form on which the primary is wound was 
originally a strip of ordinary cardboard (or 



fiber may be used), about three and a half 
inches high and sixteen inches long. Slots 
are cut to three quarters of an inch from the 
lower side, leaving half inch segments with a 
quarter of an inch between them. The form is 
then bent and permanently made into a cir- 
cular tube. The finished form must have an 
odd number of slots and segments. After 
the wire is wound, the top of the coil is en- 
circled with a strip of cardboard made fast 
with glue, or eyelets as Mr. Brown has done. 
The secondary of the coupler is an ordinary 
spider-web. 

BUILDING YOUR OWN LAB 

THIS month's suggestion is a handy little 
device that only recently found its way 
to our own work-bench. Photograph 
10 shows the Nestor "Bend-Rite" a genuine 
aid to the art of neat wiring. It is a wrench 
arrangement that may be used for bending large 
and small bus-bar wire, and for making eye 
holes to pass both number six and number 
eight screws. It is in this last operation that 
the "Bend-Rite" shows its true worth, and 
the behind the panel neatness of the receiver 
shown in Fig. 5 pays tribute to this handy 
device. 

The " Bend-Rite" is made to be permanently 
screwed to the work-bench or table, but the 
experimenter will probably find it more con- 
venient to clamp the tool in a vise, and shelve 
it when not in use. 




The "Bend-Rite" arrangement. This little wrench 
device may also be used for making excellent 
tail-washers from short lengths of bus-bar wire 



Supplemental List of Broadcasting Stations in the United States 

LICENSED FROM MAY 17 TO JUNE 13 INCLUSIVE 



' 


= : ! ~ 




WAVE- 


POWER 


CALL 


LOCATION 


KILOCYCLES 


LENGTH 


(Watts) 


LETTERS 










KFPO 
KFPT 


Denver, Colo 
Salt Lake City, Utah 


I3OO 
833 


231 
360 


500 
500 


KFQA 
KFQD 
KFQE 
KFQF 
KFQG 
KFQH 
KFQI 
KFQJ 
KFQK 
KFQL 
WCAY 


St. Louis, Mo 
Anchorage, Alaska 
Colorado Springs, Colo. . 
Minneapolis, Minn 
Los Angeles, Calif 
Hillsbourgh, Calif 
Culver City, Calif 
Oklahoma City, Okla 
Fayette, Mo 
Muskogee, Okla 
Milwaukee, Wis 


I I 5O 
I07O 
1340 
1340 
1330 
I3OO 
. . 1280 
1270 
1270 
1190 
H30 


280 
224 
224 
226 
231 
234 
236 
236 
252 
266 


5 

100 

5 
10 

IOO 

50 

IOO 

50 

10 
20 
25O 


WDBI 


St. Petersburg, Fla 


1330 


220 




WDBO 


Winter Park, Fla 


I25O 




5 


WDBP 


Superior, Wis 


I I 5O 
n8r\ 


20 1 


5 

IO 


WDBQ 


Salem, N. J 




r 


IOO 


WDBR 
WDBS 
WDBT 
WDBU 
WDBV 
WDBW 
WEBH 


Boston, Mass 
Dayton, Ohio 
Hattiesburg, Miss 
Skowhegan, Maine 
Fort Wayne, Ind 
Columbia, Tenn 
Chicago, 111 


IO6O 
1270 

1160 
1160 

I 120 

... 810 


283 
236 
258 
258 
268 
370 


5 

10 
IO 
IOO 
20 
IOOO 


WFBW 


Cincinnati, Ohio 


97 


309 


75O 


WJAB 
WJAZ 
WKBF 
WLBL 


Lincoln, Neb 
Chicago, 111 
Cranston, R. I 
Stevens Point, Wis 


1310 

I 120 
1050 
1080 


229 
268 
286 
278 
if, i 


20 
5OO 
5OO 


WMAZ 
WQJ 
WSAU 
WSAV 


Macon, Ga 
Chicago, 111 
Chesham, N. H 
Houston, Texas 


I I 5O 

: 670 
1310 
833 


448 
229 
360 


5OO 
IO 
IOO 



LIST OF BROADCASTING STATIONS DELETED MAY i TO MAY 30 



LOCATION 



LOCATION 



KDZQ Denver, Goto. 

KFCH '. Billings, Mont. 

KFDR York, Nebr. 

KFLP .... Cedar Rapids, Iowa 

KFLY Fargo, N. Dak. 

KZN Salt Lake City, Utah 

WBBE Syracuse, N. Y. 

WBL .... Anthony, Kans. 



WGN Chicago, 111. 

WHAP Decatur, 111. 

\VIAU Le Mars, Iowa 

WMAP . Easton, Pa. 

WOAD ......... Sigourney, Iowa 

\VPAP Winchester, Ky. 

WSAX . Chicago, 111. 

\VTAH Belvidere, III. 



MEXICAN BROADCASTING STATIONS 



CALL LOCATION 
LETTERS 


KILOCYCLES 


WAVELENGTH 


POWER 

(Watts) 




545 to 857 


350 to 550 
350 to 550 
350 to 550 
350 to 550 


250 




. . 545 to 857 


r^VP M-aiatlan 


. . . . 545 to 857 


CYX Mexico City 


545 to 857 



TOTALS 



Number of U. S. broadcasting stations . 
Number of Canadian broadcasting stations 
Number of Cuban broadcasting stations . 
Number of Mexican broadcasting stations 



601 

44 

34 

4 




The D X Con 



MRS. EVA L. RHODES 

Who won the first prize for ready-made receivers in RADIO 
BROADCAST'S third distance receiving contest. She 
received a MuRad MA-ij, six-tube radio frequency set 



MEET the winners of RADIO BROADCAST'S 
third annual distance contest. Last month, 
we announced their names and the prizes 
they received, but the scarcity of available space in 
the magazine made it necessary to hold over their 
photographs until this 
number. These are the 
six fortunate ones out 
of a very large group 
of contestants who 
brought all their dial 
twisting cunning to win 
the six prizes, three for 
home-built receivers, and 
three for ready made 
sets, in the contest re- 
cently closed. 

Those who entered the 
contest and were not 
successful and those who 
did not enter it and 
have since wished they 




M. F. WINNE 

Of Webster Groves, Mis- 
souri, second prize winner 
in the home-built receiver 
group. His home-made 
neutrodyne brought in a 
total distance of 1 1 5,088 
miles. The photograph of 
Mr. Winne's set showed 
one of the neatest and 
best built we have seen 



had, and those who are 
interested in distance 
reception anyhow all 
doubtless would like to 
know what sort of re- 
ceiver did win out in 
the two groups. 




O. B. EVANS 

Of Mount Pleasant, Michigan, whose one-tube Michigan 
Midget receiver, appearing in the photograph together 
with its owner and his dog gained second place in the 
contest with a distance of 84,620 miles. His prize was 
a Fada neutrodyne receiver, model "160" 



THE RECEIVERS THEY USED 

MRS. EVA L. RHODES, of Utica, New York, 
who logged a distance of 85,510 miles used a 
Paragon RA-io receiver with a DA-2 detector- 
amplifier unit of the same manufacture and a IO-R 
radio-frequency amplifier. The other equipment 
included a Fibretone loud speaker, and a Malone- 
Lemmon Control-o-Meter. 

O. B. Evans, of Mount Pleasant, Michigan, who 
came in second in the manufactured set group, used 
a Michigan Midget one-tube receiver. He used 
Brandes receivers, and his antenna was an inverted 
L type 102 feet long which was alternated with 
an indoor cage antenna containing 61 feet of No. 
14 wire. 

Alex. B. Nicol, of Bogota, New Jersey, who won 
third place with his Atwater-Kent No. 10 Radio- 
dyne, logged a total distance of 68,520 miles. He 
used an 8o-foot single wire antenna, 25 feet high, 
Western Electric phones, and Atwater-Kent loud 
speaker. 



test Winners 



HOME-MADE WINNERS 

DR. W. C. WOLVERTON, of Linton, North 
Dakota, who won the first place in the home- 
built set group, used an assembled neutrodyne re- 
ceiver to gain his mileage of 121,535. He used the 
following parts: 

Freed-Eisemann neutroformers and neutrodons 

WorkRite non-microphonic sockets 

All-American audio transformers 

Dubilier 1 micadons 

Star Rheostats 

Standard Two-Circuit jacks 

Freshman .006 mfd, fixed condenser (mica). 

Baldwin and Bran- 

des phones 
M urdock multiple 

plug 

Baldwin loud 
speaker, with 
Weston plug 





KENNETH DANIELSON 

Of Thermopolis, Wyoming 
came in a good third for the 
receivers in his class with a 
distance of 135,190 miles. His 
receiver was also a home- 
assembled neutrodyne which 
was built from Freed-Eisemann 
parts 



additional audio am- 
plifier unit using 
2 Air-Way audio 
transformers 

M. F. Winne, of 
Webster Groves, 
Missouri, won sec- 
ond place in the 
homebuilt receiver 
class with his dis- 
tance of 115,088 
miles. His home- 
built neutrodyne is 
an exceptionally well 
made one. Besides 
home made neutro- 
dyne parts, he used 

Carter .04 mfd. fixed condenser; Carter rheostats; Fed- 
eral audio transformer; Royal sockets; Ezytoon dials; 
Western Electric phones. 

His antenna is a single wire, 90 feet long, stretched 
from a window of his house to a tree, 45 feet from the 
ground and free from all obstructions. His location 
is apparently an excellent one for receiving. 

Kenneth Danielson, of Thermopolis, Wyoming, 
whose total distance of 135,190 miles won him third 
place, used a neutrodyne receiver which he as- 
sembled from Freed-Eisemann parts. Most of his 
reception is done on Baldwin phones, although he 
uses a Magnavox R-2 loud speaker on strong signals. 
His antenna is a single wire 65 feet long, 35 feet above 
ground. 

Mr. Winne got the parts for a Roberts two-tube 
knock-out with one stage of audio, and Mr. Dan- 
ielson the parts for a Roberts set as his prize. 



DR. W. C. WOLVERTON 

Of Linton, North Dakota, whose home-built neutrodyne 
receiver won first place in that class with a logged distance 
of 121,535 miles. The set is excellently assembled and 
neatly wired. His prize was a complete set of parts for a 
Haynes super-heterodyne 



CONCLUSI0NS 

THE neutrodyne receivers seem to have it by 
acclamation in the home-built receiver class, 
for every one of the winners in that group used such 
a receiver. Some of them were built entirely by the 
constructor, and others used some manufactured 
parts. The winners in the other group also depended 
on radio-frequency amplification, very largely. 
Mrs. Rhodes attained success using a radio frequency 
unit ahead of her regular receiver. 

The letters which came 
in with the contest en- 
tries were almost unani- 
mous in their condemna- 
tion of the single-circuit 
regenerative receiver, 
and almost all reported 
continuous interference 
from this type of set. It 
is distinctly worth not- 
ing that excellent dis- 
tance was attained by 
these contest entrants all 
of whom used non- 
radiating types of sets. 

In later issues, we 
shall publish photo- 




ALEX B. NICOL 
Of Bogota, New Jersey 
came out third among the 
contestants with ready- 
made receivers. He logged 
68,520 miles with an 
Atwater-Kent No. 10 
Radiodyne, and received 
a Sonochorde loud speaker 
as a prize 



graphs and brief descrip- 
tions of some of the 
very excellent sets which 
were entered in the con- 
test. 



A Word About Radio Broadcast's 
Knock-Out Receivers 

How They Came to be Featured so Strongly How 
to Tell Which of Them Will Best Suit Your Needs 



BY ARTHUR H. LYNCH 



WE FEEL perfectly justified 
in stating that no group of 
radio receivers, with the 
possible exception of the 
neutrodyne and the super- 
heterodyne has achieved anything like the suc- 
cess and favor among the radio public that our 
own Knock-Out series has received. And so 
we tell some of the story. 

From the first numbers of RADIO BROADCAST, 
its editors have been of the opinion that whist- 
ling receivers were a menace not alone to good 
reception but to the entire radio industry. 
Many of you, who have followed our activities 
will remember that hardly a number appeared 
that did not contain some reference to this 
nuisance. 

Many reputable manufacturers did not agree 
with us in our stand, and some of them went so 
far as to tell us that unless we ceased our criti- 
cism of the receivers on which they were making 
their living they would discontinue advertising 
with us. This magazine, like most others, de- 
pends to a great extent on advertising revenue 
for its life. We held a council of war and de- 
cided to stand by our guns and unless we could 
tell the truth, not half-truths, we would dis- 
continue publisning in the radio field. Some 
advertisers did pull away from us and we lost 
their business, but we gained something far 
more valuable the confidence of our readers. 
Other advertisers began to believe our doctrine 
and realized that in the long run the family 
that could afford an expensive receiver would 
not buy it if the entertainment it would provide 
could be and would be subject to the whims of 
other families in the neighborhood operating in- 
terfering receivers. Then, too, we had the 
parts manufacturer and the retail dealer to con- 
tend with. Contention it was, because neither 
would agree that a policy that would reduce 
sales, even temporarily, was a good policy to 
pursue. 



HUMAN NATURE, BLOOPERS; THE GOLDEN RULE 

THERE isn't any problem to it," said the 
manager of one radio store. "Human 
nature is human nature, and just as long 
as the cheapest receiver that brings in long dis- 
tance is one of your so-called "bloopers" the 
public is going to buy it. The golden rule days 
have not yet arrived. And from a purely 
business standpoint, it is necessary for me to 
sell these receivers to stay in business, because 
if I didn't someone else would, and the money 
is just as good to me as to any one else." 

Eminent radio experts and many self- 
appointed radio engineers went to a lot of 
trouble to advocate the continuance of the sale 
of receivers that could and did radiate. Their 
arguments have appeared in the radio sections 
of many newspapers as well as in some of the 
radio monthlies. 

One of the simplest methods to show the 
menace of radiating receivers was to have 
every listener in this country attempt to listen 
for the same broadcasting station at the same 
time. By cooperating with The Wireless 
World & Radio Review and British Broadcasting 
Company in London, and the broadcasting 
stations here, we were able to carry on our 
transatlantic tests last November. American 
broadcasting stations Kept silence while listeners 
throughout our country endeavored to pick up 
signals from England. The reports from all 
who took part in these tests show that the 
greatest drawback was the interference caused 
by radiating receivers. 

THEN CAME THE CAUSTIC EDITORIALS 

RADIO editors in all sections of the country 
began writing highly vitriolic editorials 
condemning the bloopers. What could be 
offered as a substitute? What type of re- 
ceiver would be as easy to operate, a? 
selective, and as economical? There was but 
one such receiver that we knew of (excepting, 



A Word About the Knock-Out Receivers 



340 



of course, the commercial type neutrodynes, 
reflexes and other non-radiators) that would 
fill the bill for those who rolled their own. 
We had tried every receiving gadget we could 
lay hands on, but the search was fruitless until 
we happened to get into the laboratory of a small 
radio company in New York. Here we found 
the single-tube reflex which was described in our 
November number, and because it was so far 
superior to any single tube receiver we had ever 
seen, we called it a "Knock-Out." Itwasfromthis 
receiver that the Knock-Out series developed. 

There is little need, therefore, further to ex- 
pand the merits of the Knock-Out one-tube 
reflex. It is, we believe, the best all-round 
single-tube receiver ever made. It is cheap, 
easy to assemble, and is easy to operate and it 
does not cause interference. 

OVER-ENTHUSIASTIC CLAIMS 

IN PRESENTING new developments in re- 
ceiver design to our readers we have always 
attempted to use moderation in making claims 
for their performance. Sometimes this mod- 
esty on our part has caused easily impressed 
construction enthusiasts to build inferior re- 
ceivers described in other publications for which 
glowing and frequently very optimistic claims 
were made. The result has been that many of 
those arrangements which have been heralded 
from the housetops as wonderful have been 
discarded for more reliable circuits that have 
appeared in our pages. The following unso- 
licited letters, which are but two among hun- 
dreds, indicate quite clearly how this system of 
conservatism is working out. 

In the November number of RADIO BROADCAST, which 
we accidentally ran across a short time ago, "young son" 
and I read Mr. Harkness' article describing the "knock- 
out" one-tube reflex. Now we had built a number of sets, 
some good, some bad and others indifferent. Particularly 
did we expect great things of a one-tube reflex that was 
widely heralded last summer, only to be disappointed by 
its working in our hands. 

However, the "knock-out" looked good to us and we 
proceeded to build it, and let it be said that as a result of our 
first night with it we were tickled pink. On K S D with 
our Western Electric loud speaker it filled the house. In 
rapid succession then came W O O, W M C, W O A W, 
W FA A, W D A P, WC A E, WOC.and W E A F. It 
was Sunday night and hearing WOC announce organ 
music, we adjusted the dials to tune-in more clearly and 
then, after listening to an organ selection that came boom- 
ing in, judge of our surprise on hearing W E A F announce 
the Skinner organ program instead. The "knock-out has 
now a permanent place in our cabinet alongside a much 
more expensive and pretentious set. 

JOHN N. McCAUGHAN, M. D., 
St. Louis, Mo. 



Three rousing cheers for RADIO BROADCAST and the 
Roberts reflex set. First we had the Harkness, which was 
a dandy set for local broadcasts, and now we have the 
Roberts that is fine for local and excellent fot distance 
too. 

Our problem here is to get by our four 5OO-watt stations 
operating simultaneously on 276, 360, 395, and 469 meters 
and get KPO at Frisco and KGO at Oakland on 423 and 
312 meters respectively, and taking into consideration also 
that a set good for 1000 miles east of the Rockies wil! 
do well to cover half that distance on the Pacific slope. 
My receiver will do this, and in addition, gives me more 
volume on the locals than the Harkness with an extra 
stage of audio. . . . The idea of seeing a hookup 
through to the bitter end is an excellent one, and a re- 
lief from the galaxy of new hookups constantly appearing 
elsewhere. 

G. L. KING, 
Los Angeles, Cal. 

HOW THE RECEIVER DEVELOPED 

THERE are many who desire volume 
enough for loud speaker operation at all 
times and for them we have built up the two- 
and three-tube sets. 

In designing these receivers, we have always 
endeavored to prevent our search for really 
satisfactory results from running away with 
our sense of duty to our readers in the matter of 
expense involved. For this reason the design 
of the Knock-Out two-tube and Knock-Out 
three-tube sets was made with a view to keeping 
the cost to the builder down as low as was con- 
sistent with good operation. Then, too, it was 
necessary to include in the design only such 
units as a builder could reasonably expect to 
find in the small dealer's shop or could be made 
at home with comparative ease. 

But, despite these efforts improvements 
came more rapidly than we bargained for, and 
where the builder can afford a set employing 
two or more tubes we feel that it is better for 
him to use the system described by Walter 
Van B. Roberts in our April and May numbers 
or by J. E. Roberts in this number. 

Our tests on the Roberts receiver indicate 
that it is almost as far superior to the single- 
tube reflex as that receiver was above other 
single-tube arrangements. For selectivity, 
economy of operation, ease of adjustment, etc., 
we know of no other receiver tube for tube 
that compares with it. 

That does not mean that the builder of a 
receiver of the older type should junk it if it is 
operating satisfactorily. If you are one of 
those builders who builds a set for the enter- 
tainment received from broadcasting and your 
present receiver gives satisfaction, keep it, 



The Vacuum Tube as an Amplifier 

Explaining the Action of the Tube in Radio- and Audio-Frequency 
Circuits The Advantages of Amplification at Radio Frequencies 

WHAT MAKES THE WHEELS GO 'ROUND: VI 
BY WALTER VAN B. ROBERTS 



For those who have wondered just "how and why" the vacuum tube works in radio- and 
audio-frequency amplification, here is a clear and concise answer to their perhaps unasked 
questions. Mr. Roberts discusses regeneration, inductive, or tickler feed-back, and the 
relation that the size of tubes and their elements bears to this phenomena. As the other 
articles in this series, this article may be read as an entity in itself, although it fits in with 
the others in the group. THE EDITOR 



WHEN radio waves of the 
frequency for which the an- 
tenna circuit is tuned are 
coming in, the high-frequency 
currents flowing in the coil 
produce high-frequency variations of the grid 
potential which in turn produce high-fre- 
quency currents (of considerably greater 
energy) in the plate circuit. If we could 
"feed back" some of this high frequency 
energy to the antenna circuit it might help 
the radio waves in their job of maintaining 
the high frequency current in the antenna 
circuit. This can be done in several ways. 
A very common method is shown in Fig. 24. 
To make the circuit conform to actual practice, 
the grid leak and condenser system of detec- 
tion is shown and a fixed condenser is shunted 
around the phones to offer the high frequency 
currents a path of lower reactance than 



through the phones. (This reactance is, how- 
ever, so high for voice-frequency currents that 
they mostly go through the phones.) The 
essential addition to the circuit is, however, the 
coil in the plate circuit. This is called the 
"tickler" coil and upon being brought up near 





FIG. 24 



FIG. 25 

the antenna coil its mutual inductance or 
transforrher action affords a means by which 
energy from the plate circuit is fed back into 
the antenna circuit. The tickler must be 
connected the right way too, for if the connec- 
tions are reversed its effect will be to reduce the 
antenna current instead of increasing it. The 
nearer the coils are brought together the greater 
will be the effect. If brought too close together 
a point will be reached where more power is 
being fed back to the antenna circuit than is 
being dissipated therein by heating the resis- 
tance of the circuit. When this happens all 



The Vacuum Tube as an Amplifier 




FIG. 26 

the currents build up rapidly to an amplitude 
so great that our assumption i p K (B + [i X 
grid potential) 2 is no longer correct, and the 
amplifying power of the tube has fallen to a 
value where only as much energy is being fed 
back to the antenna circuit as it is dissipating. 
The tube is then said to be oscillating and will 
continue to oscillate even if the radio waves 
cease coming in. The loudest signals are ob- 
tained just before the tube " breaks into oscilla- 
tion." Signals can be received even while the 
tube is oscillating if the oscillation frequency 
is kept exactly the same as the carrier wave 
frequency, but this is very difficult. 

5O. PLATE VARIOMETER REGENERATION 

FIG. 25 shows another common way for ob- 
taining regeneration. The variable in- 
ductance in the plate circuit is not near enough 
to the antenna coil to have any appreciable 
"tickler" effect, but it is nevertheless capable 
of producing regeneration as follows: just as the 
radio-frequency currents flowing in the coil of 
the antenna circuit cause radio-frequency 
fluctuations of the grid potenital, so do the 
radio-frequency currents in the plate circuit 
cause fluctuations in the plate potential. On 
account of the close proximity of the plate to 
the grid the fluctuations of plate potential 
affect the grid potential and it can be shown 
that the effect is to re-enforce the grid potential 
fluctuations caused by the antenna current. If 
the variometer or variable inductance is grad- 
ually made greater, the amount of regeneration 
will increase until, just as with tickler regenera- 
tion, the tube breaks into oscillation. (If a 
high resistance or a large condensive reactance 




were used in the plate circuit instead of the 
inductance there would also be fluctuations of 
plate potential, but the effect, if any, would be 
to diminish the grid potential variations.) 

51. IMPEDANCE AND RESISTANCE COUPLING 

THERE are two general methods for ob- 
taining amplification by means of vacuum 
tubes. The method of impedance coupling 




FIG. 28 

shown in Fig. 26 is the one least used. The 
total voltage amplification attainable per 
stage (in Fig. 26 this would be the ratio of the 
alternating voltage on the grid of the second 
tube to the alternating voltage supplied to the 
grid of the first tube) cannot be greater than 
the voltage amplification constant of the tube, 
and in practice is usually considerably less. 
Hence to get good amplification by this 
method, special tubes having high values of [x 
must be used. The impedance indicated by 



7- 




FIG. 27 



50 100 200 400 800 1600 5200 WOO 
FREQUENCY, CYCLES PER SECOND 

FIG. 29 

the letter Z in Fig. 26 may be either a high 
resistance or a high reactance. The alternat- 
ing grid potential applied to the first tube 
causes alternating current in the plate circuit.