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Full text of "73 Magazine (October 1969)"

WORLD'S LARGEST 













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NOW AT YOUR DEALERS! 

FROM THE MAKERS OF THE FAMOUS GALAXY TRANSCEIVERS 




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The Galaxy FM-210 2 Meter FM Transceiver 

Now every Amateur can buy Galaxy's well-known quality 
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(or 10 watts with the optional AC-DC Power Booster 1) Check these 
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See one..Jnj one! 

SPECIFICATIONS 



Frequency range; 143-149 MHz. Antenna Impedance: 50 Ohms Nominal 
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Transmitter: Power Input: 5 watts (10 W. with pow, booster) • Freq. Con- 
trol; 3 Chan, crystal controlled • Microphone: High Impedance 
req'd. • Deviation; Adi. narrow or wideband with clipper filter 
also adj. for optimum clipping level. 

Receiver: Sensitivity: SIN AD -5uv for 12db, luv provides 20 db quieting. 

• Adjustable squelch • Modulation Acceptance: FM wideband 
(narrow band available) • Type: Dual Conversion, FET front end 
for minimum cross modulation and overload • IF Frequencies: 
10,7MHz and 455 KHz • Freq, Control: 3 chan. crystal controlled 

• Audio Output: 3 watts (intr'nl 3.2 spkr.) 

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galaxy electronics 

"Pacesetter in Amateur/Commercial Equipment Design" 
10 South 34th Street • Dept.73-FF46* Council Biuffs, Iowa 51501 



It-- 





0^ ^ G .Au 2 I isr 



PETERBOROUGH, NEW HAMPSHIRE 03458 



73 Magazine /1 09, October 1969 



Features 

2 de W2NSD/1 

II Sotderiog Aid 
13 Try This One 
31 Autobandwidth 

39 ^Mobile Heater Switching 

49 IShJetded Braid 

75 Simpte Code Oscillator 

III New PrcxJucts 

113 ^opagati on 

114 Crossword Puzzle 
122 euy or Rent 

128 ZL to SM Moonbounce 

128 New Amateur TV Record in VK ! 

128 New 1296 mhz VK Record 

131 Errata 

134 L«ttsr^ 

141 Caveat Emptor 

144 Index to Advertisers 



STAFF 

Editors 

Wayne Green W2NSD/1 
Kayla Blook WIEMV 

Advertising 
Diane Shaw 

Production 
Roger Block 
Phil Price 
Nellie Sildar 
Jeff Barsanti 
Jane Tracey 
Whitney Tobias 

Art 

Bill Moreflo 
Mike Baltin 

Circulation 

Lin Green 
Dorothy Gibson 
Carol Ring 

Comptroller 
Joe LaVigne 

Propagation 

John Nelson 

WrW Editor 

Dave Mann K2AGZ 

BoQks 

Wafter Manek 
Mark Kearney 



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12 
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24 
28 
32 
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42 
46 
50 
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54 
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62 
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S8 
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73 
76 
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86 
108 
116 
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124 
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Contents 

A Super^Gain Antenna for 40 Meters .,..,,,,,». W4ISIVK 

Nine db on 40 meters might be called *'super/* 

DX Corner , ___.,, K2AG2 

WTW reports and other DX jazz. 

FET Chirper , .,....., K6QKL 

Signet source for peaking converters for optimum signal /noise* 

The inside Info on Alexander Graham .,**.,,,.,.,,.,, ,W2FEZ 
Or— how the telephone really works. 

Leaky Lines ,,-,,,,.,... , . ^ , . • . K2AGZ 

Similar to "Grumbles/' but by a licensed amateur, not a CB'er 

Scope Calibrator , . . . . , , , , , _ W10LP 

Gadget you can build to improve your scope. 

Vidiots That Have Known Me . > * , *K1 YSD 

Sense of iiumor test. If you flunk, go back to 11 meters. 

The Protector , ..,.,. WA0 HKC 

Protects your gear from sudden line voltage surges and interruptions. 

Slower Tuning Rates for Older Receivers . , , , W4RNL 

Just like band spread. 

Positive Identification of Calibrator Harnrionte .__->,,-., K5LLI 

Keeps you off 6950 and other poor DX bands. 

Adapting AM Transmitters to FM ,,,.,.,. .WA4UZM 

Good Heavens, is everyone going on VHF FM? 

CB Sets on Six , . . WB2FHW 

No need to junk that C8 rig when you get your Tech ticket. 

Proportional Controt Crystal Oven ..,*,*,,*,,,,** W2CLL 

You need this sort of thing for moonbouni:^ work and such. 

A Crystal Filter Phasing Control . . ,,,,.. . , . , ,W2LT 

Look at the i-f response in Fig. 10 and be amazed. 

Grounded Grid Filament Chokes . , , W2|K 

You need these for linear amplifiers. 

Equipment Cabinets with Style . * . . * • , . . . .W20LP 

Make it look commercial. 

VHF-FM: Part I , , .^. ...•-.. . . . . _ WB2AEB 

Advantages and practices. When sre you going on FM? 

Bring Back the Q Multiplier , W8RHR 

Invaluable for CW, notches out AM carriers, etc. 

Activation in VP2 , . . VP2AC 

Anguilla Island activated. 

The CR Beam . . . , , _ . _ _ WA4FDQ 

Two meter corner reflector beam. 

The ARRL Board and Amateur Radio , ^ ,**.**.<**,, , 
An ex -ARRL Director evaluates the latest board meeting, 

A Cheap and Easy Power Supply 

For a sideband transceiver. 

Extra Class License Course, Part fX 

Modulation. We'll have lots of arguments on this one. 

Ham Jamboree • , 

Scouts hit the ham bands every October- 
Operation Cat's Paw .•.*..•,..... 

Whimsy. 

Knight V-107 VFO for Six and Two Meters , K6GKX 

Test report by a happy user. 

Careers in the F AA . . ,,.,.. , W6JTT 

Get on the government payrolL 

Youth Forum ..,....»,•• •....,....* WAIGEK 

Teenagers, arisel 



, _W7ZC 



K4FQU 



. .Staff 



WB6IZF 



..W7ZC 



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73 Magazine is published by 73 Inc.^ Peterborough, N,H. 03458, Subscription rate: $12.00 for three 
yearSj $6.00 for one year. Second Class Postage paid at Peterborough, New Hampshire, and at 
additional mailinfi offices. Printed at Pontiac, Illinois, U.S.A. Entire contents copyright 1969 by 73 
Inc, Peterborougn, New Hampshire 03458. Address label cypher: your call letters should follow your 
name. If we've had to make up a call just drop us a note and we'll change it to your real call. The 
number under the caU is our code for the last issue on your subscription. The first number is the 
month, the second the year of the last issue, 50 would indicate expiration with May, 1970. Renewal 
notices are prepared ahead of time and you may receive one or two after your subscription has been 
renewed. View tlus situation with humor and tolerance. Tell your friends about it, ii you must^ but 
don^t feel it necessary to teU us. We already know all too well about it. 



OCTOBER 1969 



1 



Gravity Waves 
Solution to Vietnam? 
Making Extra Money 
Making $1,000,0001 
Reactionaries 
Marathon Nets 
FCC Actions 



...de W2NSD/1 



Wayne Green 



p 



Gravity Waves 

My thanks to old friend Neil W20LU for 
sending in a clipping from the New York 
Times announcing that Professor Weber of 
the University of Maryland has detected 
gravitation waves. The existence of gravita- 
tional radiation is predicted by Einstein^s 
General Theory of Relativity and Professor 
Weber beheves that he has experimentally 
verified Einstein's prediction* 

A century ago Maxwell predicted from 
mathematical calculations that there were 
other types of electro-magnetic radiation 
than light rays. In 1888 Hertz confirmed 
Maxwell's predictions and opened the radio 
spectrum. 

As I mentioned a few months ago^ here is 
a field that is wide open for the amateur. 
There are no professionals in the field yet. 
What, all of us want to know, is the velocity 
of propagation of a gravity wave? Speed of 
light? Instantaneous? If it is faster then it 
would make a wonderful communication 
medium for interstellar contacts . . , and 
miglit explain how those pesky UFO's are 
able to get here from planetary systems so 

far away that reputable scientists say that 
they cannot exist just because there is no 
possible way for them to come that distance. 
If you have any info to pass along on 
gravity generators or detectors, let's pass it 
along through 73. 

Vietnam Solution? 

The educated opinion seems to be that 
President Nixon has been hoping that he 
could use the same route for settling the war 
that Eisenhower used for closing out the 
Korean conflict. That meant working 
through Moscow, who, because of the Chi- 
nese difficulties, were supposed to be 
anxious to accomodate the U,S, 

This approach doesn't seem to have 
worked out in practice at all, a situation 



which leaves us still boiling in our own kettle 
of soup. Unilateral disengagement means, 
essentially, the slaughter of most of South 
Vietnam, the historic consequence of losing 
a war in Asia. This, in turn, can hardly help 
the non-communist forces in Laos, Thailand, 
Cambodia, Malaysia, Burma and India, Any 
promises we have made in the past of help 
wiU hardly be honored after the disaster in 
Vietnam, and they know this* 

Obviously, getting out of Vietnam unilat- 
erally is a very bad solution to our problems. 
Should we then turn around and escalate 
again? We have seen that the communists are 
able to match every escalation. They have no 

intention whatever of losing the war. They 
have been at it for many years there and are 
not about to drop it now. 

This is a subject that can better be argued 
in a bo ok -length form than a brief editorial 
comment such as this, however I would Uke 
to make an abbreviated suggestion for a new 
course of action that might possibly prove 
more rewarding. 1 wrote about this a couple 
years ago upon my return from Asia, but not 
much came of it. The ideas still seem quite 
valid . . . perhaps even more valid than ever^ 
since more options have been tried in the 
meanwhile without noticeable success. 

Basically, I propose that the Pentagon 
and the State Departments do not have a 
corner on the U,S, brain market. Experience 
has rather indicated negatively in this re- 
spect. Possibly then, we could do better thaa 
depend upon them for our total effort in 
Vietnam, directing the fighting and peace 
talks, which about sums up our activities 
there. 

Just suppose that we decided to fight a 
much more basic fight, using our biggest 
weapon? The bomb? No, not at all. The 
battle between communism and capitalism is 



73 MAGAZINE 



For The Experimenter ! 

International EX Crystal & EX Kits 

OSCILLATOR / RF MIXER / RF AMPLIFIER / POWER AMPLIFIER 



Available from 3.000 KHz lo 60,000 KHz. Supplied only in 
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OX circuit or its equivalent* (Specify frequency) 



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Lo Kit 3,000 to 19,999 KHz ^ 
Hi Kit 20,000 to 60.000 KHz ^ 
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MXX-1 Transistor RF Mtxer $3.50 

A single tuned circuit intended for signal con- 
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Lo Kit 3 to 20 MHz 

Hi Kit 20 to 170 MHz 
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A small signal amplifier to drive MXX-1 mixer. 
Single tuned input and link output. 

Lo Kit 3 to 20 MHz 

Hi Kit 20 to 170 MHz 

(Specify when ordering) 

PAX-1 Transistor RF Power Amplifier $3.75 

A single tuned output amplifier designed to 
follow the OX oscillator. Outputs up to 200 mw 
can be obtained depending on the frequency 
and voltage. Amplifier can be amplitude modu- 
lated for low power communication. Frequency 
range 3,000 to 30,000 KHz. 

BAX-1 Broadband Amplifier $3.75 

General purpose unit which may be used as a 
tuned or untuned amplifier in RF and audio 
applications 20 Hz to 150 MHz. Provides 6 
to 30 db gain. Ideal for SWL, Experimenter or 
Amateur. 

IVr/fe ioT comptefe catafog. 




INTERNATIONAL 




CRYSTAL MFG. CO., INC. 

10 NO. LEE • OKUA. CITY, OKLA. 73102 



OCTOBER 1969 



wmm 



most fundamental. Why not use capitalism 
as a weapon? This is one weapon that has 
been almost irrestible so far and yet we have 
made little effort to use it. 

For a fraction of the $100 million a day 
we are spending in Vietnam we could ship 
production machinery from the U.S, to set 
up factories around Vietnam. I envision a 
change from the present agricultural system 
to a half agricultural, half industrial system, 
with factories spread out so that workers can 
continue to farm part time, I wonder if this 
isn*t a happier way of living than our 
all-or-nothing arrangement? 

Factories in undeveloped countries are 
rather basic affairs and far less expensive 
than those in our country. With a relatively 
smaH investment we could spread factories 
all over Vietnam, providing jobs part time in 
hundreds of villages. Would the people make 
the change? If the incentive is there, they 
win. The incentive that I have seen change 
one country after another into industrial 
countries has been the availability of inex- 
pensive cars and television sets. People wiU 
work incredibly hard for these pleasures. 

Suppose we set up a few dozen factories 
making prefab huts and basic furniture and 
gave these products to the Vietnamese, along 
with a small plot of land for a garden? Not 
only would we be able to clean up the 
miserable camps now housing thousands of 
refugees, but we would also have something 
very interesting to offer defectors from the 
North. Cars, TV, and other luxuries would 
have to be earned. 

The whole bill for a give-away program 
like that might come to $1000 per defector, 
but that is a small fraction of what we are 
paying right now to try and kill them as they 
come down to fight. It is costing us some 
500 times that much! 

Once we convert Vietnam to a capitalistic 
system, they will be forever broken away 
from the old patterns and can soon take 
their place among those Asian countries who 
have made the change * . * Singapore , , , 
Thailand , - , Japan, There are plenty of 
markets in Asia for products manufactured 
in Vietnam since few of the neighboring 
countries are developed. 

Does that sound better than the alterna- 



tives of fight harder or quit? 

Danger 

As those of you who know me personally 
know, I love to eat and as a result I am 
generally a bit on the heavy side. Every 
couple of years or so I go on a diet and take 
off the accumulated layer. This summer^ 
egged on by the wonders of the Doctor's 
Diet, a lovely invention wherein you eat 
meat and drink water, . ,and not much else, 1 
decided to make the plunge. The book said 
that 1 could also drink all of the diet soda 1 
wanted along with the diet, so I loaded up 
on my favorite flavors of "tonic," as they 
call it up here in New Hampshire, all sugar 
free. 

Fat free beef and fat free chicken left me 
with plenty of hunger pangs, but the diet 
soda filled up the empty spaces and I found 
that I was drinking more and more each day, 
getting up to some four bottles a day. No 
harm done, so why not? 

Along about the third day I began to find 
it difficult to focus my eyes and I started 
having periods of vertigo. This got progress- 
ively worse and by the seventh day I 
couldn't even see to type, much less read 
manuscripts and proof-read articles • My eyes 
just couldn't focus any more at all, I realized 
that meat certainly wouldn't do this to me, 
and since the only other thing 1 was eating 
was diet soda, it obviously had to be that. I 
stopped. 

Within a couple of days the headaches 
stopped, the vertigo stopped and my eye- 
sight began to improve. After a week I could 
read medium-sized print again and type. 

The secret was right there on each bottle, 
if I had taken the time to read the fine print 
while my eyes were still working. That stuff 
is supposed to be only for people who have 
been requested by a doctor to restrict their 
intake of sugar . . , diabetics. In moderation 
I suppose it would not cause noticeable 
difficulty. Who would notice his eyes slowly 
deteriorating over a period of weeks or 
months and tie it in with diet soda? Even 
occasional headaches and vertigo might not 
be suspected. And who knows what other 
damage these beverages oiay be doing? They 
certainly must be able to have a profound 
effect on the human body to be able to do 
me in so quickly on such a small dose. 



73 MAGAZINE 





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OCTOBER 1969 



■■ 




Extra Income 

When people explain to me that they are 
too short of money to buy a subscription to 
73 I look at them in wonder. Short of 
money! That is truly remarkable in this day 
when there are so many simple ways of 
making money in spare time. The money is 
there for those that axe willing to go after it. 
There are so many things to sell and so 
many services to offer that there should be 
something for everybody. If you live in an 
area where you can make unlimited local 
phone calls at no extra charge, you have a 
goldmine. You can sell products or services 
over the phone. 

Take for instance selling magazine sub- 
scriptions. Most families buy at least one 
magazine subscription and some buy as 
many as a hundred a year* Why should all 
these people buy their subscriptions directly 
from the magazines when they could just as 
well buy them through you and save money 
for themselves? 

How do you get started in something like 
this? WeU, first I would write letters to the 
circulation managers of the larger circulation 
magazines on some quickly made letterhead • 
If letterhead costs too much, make your 
own with a rubber stamp on blank paper. 
You can be in business for about $2 as the 
Amalgamated Subscription Agency. You can 
find the magazine office addresses on the 
magazine masthead at your local newsstand. 
Once you have some of those juicy 
subscription agent prices in hand you can 
start caOing people right out of the phone 
book and quote them a price on buying a 
new subscription or extending their current 
subscription to Life, McCalls^ Reader's 
Digest, etc. Once you get them for a 
customer you naturally keep track of their 
subscriptions and give them a call when 
renewal time comes along* Ask them for a 
list of the magazines they read and write to 



the other publishers too. Before long you 
will be an agent for hundreds of publishers. 
You can find out about special interests 
locally too. Just as you can get a list of 
customers from a radio parts store which 
will help you sell radio magazines, also you 
can get names from a sporting goods store 
for selling sporting magazines, from a camera 
store to sell photography magazines, and 
from the sports car garage to sell car 
magazines. You can buUd up lists of dozens 
of special interests for magazine sales. 

Do I have any other money-making ideas? 
Sure, plenty- You're interested in electron- 
ics, so how about seUing some electronic 
equipment? Have you ever thought about 
selling closed circuit television installations 
in your area? Many businesses and even 
homes are excellent sales prospects for them. 
Or how about selling one of those radar 
alarm systems to the store owners locally? 

There are thousands of things to sell. You 
can sell direct from your home, over the 
phone^ or even act as a manufacturer's 
representative to sell items to local retail 
stores. The magazine Salesmen's Opportun- 
ity lists more products looking for salesmen 
than you can imagine. The Macfadden .50 
book on How To Make A Fast Buck will give 
you hundreds of more ideas. Most of the 
companies that do pub he surveys are in need 
of help from the hinterlands and the pay is 
sometimes surprising. 

One of the biggest skin diving stores in 
the country sprang from a small bedroom in 
the wilds of Brooklyn, The enterprising high 
school student rubber stamped up some 
letterhead and became a dealer for several 
manufacturers. Low overhead meant bar- 
gains for the customers and before long his 
parents were being crowded out of the 
house. Stop in and say hello to Harvey for 
me the next time you visit Sheepshead Bay. 
One of the biggest ham radio distributors 
in the country started out not many years 
ago in a Uttle comer of his father's furniture 
store. Does that give you any ideas? 

Wealth? 

A few months back there was a very snide 
reference in one of the other ham magazines 
to a little booklet I wrote a couple years or 
so back on How To Make a $1,000,000. Pve 




73 MAGAZINE 




p 



mentioned this briefly in my editorials be- 
fore, I realize, explaining that my interest in 
the matter is more academic than real. 

This academic interest does lead me to 
read most of the books that come out on the 
subject of making money or keeping it, once 
you've made it. And that can be a problem 
too* In addition to the book by Lloyd 
Colvin W6KG on making a million in the 
home construction business, I might also 
recommend the pocket books on The Rich 
and The Super Rich, and Atlas Shrugged. 
The first of these was particularly interesting 
to me because it backed up my own deduct- 
ion that college education not only does not 
help you to make big money, it in fact is a 
severe hindrance. 

Fortunately for our school system very 
few people seem to be even slightly interest- 
ed in going for the big money. By big money 
I mean enough to permit you to retire and 
Mve comfortably from the invested capital, 
not millions of dollars. 

Fortunes are not being made any more, 
just inherited. However, thanks to inflation, 
it is not at all difficult to gather together one 
little bitty million. This is being done quite 
frequently by those either shrewd enough to 
figure out the system or those lucky enough 
to fall into it, I suppose I should add a third 
group that ignore the system and get there 
by stealing. 

Even considering Parkinson's Second Law 
(expenses will always rise to meet income), 
$1 million dollars invested at a mere 5% 
should last you rather weU, You won't be a 
big yacht customer or buy a Rolls, but at 
$50,000 per year the wife shouldn't have to 
buy cloth coats for winter. 

Naturally I recognize that the preponder- 
ance of 73 's readers are inescapably com- 
mitted to their present life and that any 
discussion of a career is, for them, quite 
academic. On the other hand, few of us are 
not occasionally put in the position of being 
able to influence a younger person, so 
perhaps a bit of thinking about careers and 
the future is not entirely out of line* 

It is aU too easy to try to pass along the 
values that we have been taught. 1 accepted 
without hesitation the idea that everyorie 
that could should go through college. It 
never even occurred to me to question this. I 



think I have the matter in better perspective 
now. 

A college education, complete with 
Master's degree, is worth every dollar and 
day to the fellow who wants to work for a 
large company for the rest of his life. The 
pay is good and the Life is American Stand- 
ard, Of course it means buying most of the 
big things on time payments for many, many 
years. The house wUl never be paid for, since 
advancement in business means moving into 
a bigger house every few years with attend- 
ant refinancing. Add car payments, boat 
payments, vacation payments, etc.. 

That Uttle postcard from Cleveland Insti- 
tute that we bind into 73 every now and 
then got me to thinking- I detest those 
darned things, but as a publisher I have to 
recognize the economics of my business and 
run them now and then. At any rate, I sent 
in one to Cleveland and in a few days one of 
their nice four color brochures arrived. The 
cover letter asked me, '*Where do you want 
to be in life in one year ... in two years . . . 
in three years from now? 

My own plans are formulated, but I 
wonder how many of the younger amateurs 
have done much thinking about their future? 

There are, obviously, many fortunes to be 
made in electronics. It is one of the fastest 
growing fields in the world today. This 
means opportunity. The big corporations 
will get bigger, naturally, but thousands of 
little companies will blossom out and make 
small fortunes for their entrepreneurs. The 
little booklet that I wrote on making a 
million dollars explains a very simple 
method of taking advantage of this growth, 
starting out with nothing and getting over 
the hump in a very few years. 

One does not become a successful busi- 
nessman by starting his own business any 
more than a concert pianist succeeds by 
going on stage with no experience whatever. 
Success requires a lot of hard work and luck. 
And the harder you work the luckier you 
get. 

Something else has changed with the 
generations too, I suspect. It may be my 
own special background, but in my youth it 
was not looked down on as a goal to work 
for wealth. Now, when talking with teen- 
continued on page 126 



1 



OCTOBER 1969 



3 




Ed Dusina, W4NVK 
571 Orange Avenue West 
Melbourne, Florida 32901 



Super - Gain 
Antenna for 40 Meters 



This article gives briefly the results of a 
study to develop an antenna for the 40 
meter band which would allow the hams to 
compete somewhat better with the foreign 
broadcast stations which practically take 
over the band in the evening and ni^ttime. 
In this respect the study was a partial success 
in that an antenna was developed based on 
the theory of super gain arrays, which rejects 
QRM from low angles. After some experi- 
mental work, a super gain antenna* was 
designed for the 40 meter band which is 
extremely simple, uncritical and offers large 
gain and QRM rejection factors. 

The propagation studies and design work 
for this antenna were done at Dusina Enter- 
prises in Melbourne, Florida. 

Briefly, the antenna to be described has a 
forward gain of approximately 9 DB based 
upon engineering design data developed in 
the literature^ and in addition to the for- 
ward gain has an average of 15 DB rejection 
against low angle QRM. Therefore, two hams 
both using this type of antenna array can 
gain an advantage of about 14 DB^ improve- 
ment in signal strength and about 1 5 DB less 
QRM when communicating via high angle 
paths over short skip distances for an overall 
S/N improvement of about 29 DB, Short 
skip distances on the 40 meter band mean 
up to about 200 miles radial distance from 
the transmitter in the daytime and up to 
about 1,000 miles in the nighttime. These 
distances are selected from actual perform- 
ance measurements on the array to be 

described- 

The antenna is of the super gain class and 

consists of a single dipole antenna placed 

very close to and above a reflecting screen 

such as to limit the radiation to 90 degrees 

plus or minus 35 degrees approximately. The 

antenna is made in a very simple manner as 

follows. A 300 ohm TV type twin lead 

folded dipole is cut to the length 63 feet 2 



inches plus or minus 1 inch and is fed in the 
center with RG 58 U coax or some other 50 
ohm coaxial cable. This folded dipole an- 
tenna is suspended tautly seven feet above 
flat ground using three wooden poles or 
some other suitable support If metallic 
poles are used, it is suggested that nylon 
cord be used for approximately three or four 
feet between the ends of the antenna and 
the metal pole so as to reduce the effect of 
capacitance on the ends of the antenna. On 
the ground directly below this antenna are 
laid three reflecting wires of a noncritical 
length SLxty-five to eighty feet long. One 
wire is stretched along the ground directly 
below the antenna element. One of the 
remaining wires is laid along the ground 
parallel to the antenna but approximately 
six feet from the wire directly beneath the 
antenna. The third reflecting wire is placed 
on the other Side of the antenna such that 
when the reflecting screen is completed 
there are three wires six feet apart, one 
under the antenna and one on each side 
forming a reflecting screen about eighty feet 
long by twelve feet wide. These reflecting 
wires are laid on top of the ground but they 
may be in the ground if desired, A slightly 
higher efficiency will result if they are 
placed on top of the ground, and the 
method used here over a lawn was to cut the 
lawn very low and lay the wires on top of 
the grass. When the grass grows back out, the 
wires will stay under the turf and not be 



63*2* ti* 



-m 



30Q TW»N L€AO 



FOLDED DtPOLE 



7*0'±3' 



GROUND - 



COAX 



1 





1 



Fig. 1. Super -gain 40 meter skywire. 



8 



73 MAGAZINE 




I 



p 



othersome* The ends may be wrapped 
around laige nails and the nails driven into 
the ground to assure that the reflectors do 
not curl up on the ends. Any reflector wire 
size larger than about No* 26 will be 
adequate, and larger than No, 14 is being 
wastefuL 

As can be seem from the foregoing 
description, this antenna is sufficiently 

pie that every radio amateur can con- 
struct one. Although this antenna is in- 
tended to be used mostly for short-range 
communications up to about 200 miles, due 
to the nature of the 40 meter band, short 
skip conditions prevail much of the time at 
night and the antenna is then effective for 
distances of 1,000 miles and sometimes 
more with full gain. 

An antenna constructed in accordance 
with the directions given above yields the 
following VSWR when fed with a 50 ohm 
coaxial cable. The antenna measured was fed 
by 100 feet RG-58 cable, used No. 26 wire 
reflectors and was tested at 2,000 W PEP: 

FREQ 7.0 7-1 7.2 7.25 7.3 7.4 

VSWR 3.6 2.6 L3 LOS 1.5 3.0 

Propagation Effects 

Tests conducted in Florida on the effec- 
tiveness of tills antenna in improving com- 
munications capabilities on the 40 meter 
band revealed significant improvement of an 
amount unexpected before the tests were 
made. These tests revealed the following 
characteristics: 

Daytime Use 

Typical daytime results comparing the 
super gain antenna to a two element col- 
linear array with 2 DB"* gain and elevated 
sixty feet above the ground (maximum 
radiation at 35^ elevation) gave the fol- 
lowing comparisons* 

Stations from Alabama received at Mel- 
bourne, Florida, were typically 10 DB 
stronger on the 60 foot antenna than they 
were on the super gain array. This communi- 
cation was at a distance of about 500 miles, 
which js long skip (about 35*^ arrival angle) 
for daytime 40 meter conditions. At approx- 
imately the same time, stations in North 
Carolina, a distance of about 700 miles, were 
6 DB stronger on the high antenna than on 
the super gain array, while stations in Ten- 
nessee, approximately 700 mUes distance, 



c 



FOLDED OfPOLE 



TO* 



GROUND- 



u 



X 



■80 FT. 

REFLECTORS (3) 



e* 



-«**■ 



J 



SUPCR GAIN ARRAr END VIEW 

Fifl, 2. Super gam array end view, 

were 6 DB stronger on the high antenna than 
on the super gain array. The rejection drop 
to 6 DB from 700 mile distant stations was 
due to the loss of gain in the collinear at the 
25° arrival angle and not due to improved 
pickup on the super gain array at the lower 
angles. These data show that the super gain 
array does in fact discriminate against signals 
arriving at the lower elevation angles. Com- 
parison checks, made at the same time, on 
stations transmitting from sites in Florida 
revealed that signals originating within 80 
miles of the super gain array were approxi- 
mately 15 DB stronger and stations within 
200 miles were 1 to 12 DB stronger on the 
super gain array than on the collinear array 
at 60 feet altitude. In general, in the daytime 
a very marked increase in received signal 
level is apparent on any station within 
approximately 200 miles of the super gain 
array, and the most noticeable aspect is that 
signals that are received on the super gain 
array are much more free from QRM, 
whereas on the other antenna noticeable 
QRM, or even difficult copy, may be 
present. This is a result of the combination 
effect of the super gain antenna 9 DB gain 
plus its 1 to 15 DB rejection capability for 
low angle QRM. The 15 to 25 DB improve- 
ment in signal to QRM is very obvious- 
Nighttime performance 

In general, the super gain array gives 
approximateiy 10 DB rejection against the 
foreign broadcast stations much of the time 
but some of the time, due to the nature of 
the 40 meter band, these long distance 
signals arrive over many, many hops and 
come down within the vertical acceptance 
angle of the super gain array. At these times, 
there is little significant difference between 
broadcast interference received on the high 
collinear or the super gain array, but the 



1 



OCTOBER 1969 



super gain still boosts the transmitted signal 
greatly. At other times, when short skip is 
not predominating, there is a marked reduc- 
tion in QRM as well as increase in signal 
strength by the use of the super gain array 
for communications out to a distance of 
approximately 1,000 miles at night Under 
th^e conditions, the strength for signals 
originating within 1,000 miles is boosted 
similar to that experienced over 200 mile 
daytime paths. 

Most persons who have worked with 
array antennas on the high frequencies are 
aware of the fact that it is difficult to get a 
sixeable change in S-meter level between a 
reference antenna and even moderate sized 
array. However^ the results obtained with 
the super gain array are striking in that the 
S-meter moves appreciably, usually at least 
one and sometimes two S-units in actual 
signal level, and if the QRM level wiU be 
noticed in the quiet periods of the trans- 
mitting station, it will be found to drop 
from 3 to 5 S-units when using the super 
gain array. If the QRM is of low angle origin, 
our experience has been that this antenna 
frequently changes a QSO from barely read- 
able to armchair quality. 

Due to the extreme simpHcity of this 
antenna and to its significant improvement 
in communications on this particular band, 
plus its small size, I believe that if amateurs 
erect such an antenna and test it for them- 
selves, they win be quick to see the value of 
it and by this means more use can be 
obtained from the 40 meter band. Partic- 
ularly, this antenna woidd be an ideal 
antenna for local nets or statewide nets 
operating in the 40 meter band in the 
daytime, since it not only greatly increases 
the signal strength of the stations communi- 
cating, but significantly reduces the QRM 
leaving the state and rejects any QRM 
coming in from outside the state. 

For those amateurs wishing to study 
further on the subject of super gain antennas 
and the types of gain that may be obtained, 
perhaps the most understandable and 
clearly-written dissertation is to be found in 
"Electronic and Radio Engineering" by 
Terman, fourth edition* Discussions on pages 
903 through 908 cover the subject briefly 
and references are given there no more 



theoretical work should one desire to dig 
deeper- 
Many amateurs have from time to time 
used very low dipole antennas on the 40 and 
80 meter bands and some have remarked 
that these antennas do not perform as 
poorly as they would expect based on the 
low height These results, however, have 
been erratic because the effect achieved is 
greatly dependent upon the conductivity of 
the ground under the antenna, and no 
compensation was made for the drastic 
change in radiation resistance or the change 
in effective length for such low antennas. 
The directivity gain of the very low antenna, 
which can be up to eight times in signal 
power, is frequently attained, in part, in _ 
these low installations over moderately con- ^ 
ducting ground. However^ the counteracting 
loss in antenna efficiency suffered, unless a 
reflecting screen is placed under the antenna 
to control the enormous losses in the 
ground^ the variable reflection distance and 
low radiation resistance make the overall 
results hi^y variable from one installation 
to another. 

The use of the reflecting screen is very 
important for three reasons. First, the an- 
tenna impedance will be 5 ohms only when 
the elements are cut as described above with 
reflecting elements installed. Without the 
reflecting elements this impedance can vary 
significantly. Secondly, the efficiency of 
drop well below 5 percent in most installa- 
tions without this reflecting screen. This 
means that the overall gain of the antenna 
may be anywhere from zero gain, or perhaps 
even a loss, to a full 9 DB gain, depending 

upon the peculiarities of the soil under the 
antenna. Thirdly, without the screen the 
spacing between antenna and image is un- 
known and unstable, varying with ground . 
conditions. Due to the utter simplicity of ^ 
the reflecting screen, it is not worth the risk 
to omit it* Also, the effective length of the 
antenna varies with ground conductivity 
without the screen, so design becomes a cut 
and try affair* 

It is hoped that other amateurs will erect 
^milar antennas and mn comparative tests 
on 40 meters as well as 80 meters and 160 
meters. The 80 meter band performance of 
the super gain array has not been explored 



10 



73 MAGAZINE 





p 



yet so that the relative percentage of the 
time during which short skip conditions 
prevail, and therefore the magnitude of 
improvement possible, is unknown to me at 
this time, but will be published as soon as 
my tests are completed. However, those 
wishing to try such an antenna on 80 meters 
or 160 meters may scale the dimensions 
given, which is centered on 7250 khz, to 
obtain the design numbers. For those with 
lots of room, a group of these units oper- 
ating broadside could generate a formidable 
signal indeed, but more than about four 
units would begin to restrict coverage 
noticeably. . . . W4NVK 

* Patent disclosure fifed, 

^a-'*Maximum Directivity of an Antenna," 
H, J, Riblet, Pioc, IRE, 36 p 620, May, 1948- 

b. T, T, Taylor, Proc. IRE, 26 p 1 135, Septem- 
ber, 1948, 

c. "Physical Limitations of Directive Systems," 
t. J. Chu, J. Apl. Phys., 19 p 1163, Decem- 
ber, 1948 

d. "Directional Antennas," G. H. Brown, Pioc. 
IRE, 25 p 122, January, 1937, 

^This figuie is referenced to a dipole^ all others 

in this artkle are referenced to isotropic- 
^Reference to dipole. 

Printed Circuit Soldering Aid 

Fixing printed circuits is really quite 
simple. Just clip out the defective com- 
ponent, leaving as much lead on the board as 
possible, and solder the new component to 
the old leads. This method works, and is 
recommended by many authorities. It does 
look like a butcher job though, doesn't it? A 
much better way which doesn't take much 
more time, considering the time spent locat- 
ing the defective component , is to take it 
out completely. Usually the holes, whether 
printed through or eyelets, are plugged up 
with the old solder* Let it cool off; then 
quickly reheat and clean the holes with a 
piece of piano wire or stainless steel wire 
about *050 inch diameter. Solder wiU not 
stick to it, yet it can be formed and filed to 
a sharp edge at one end to aid in cleaning 
out the fringes of solder. A bit of masking 
tape makes a convenient handle if wrapped 
around the center portion of the tool- 
Roy A. McCarthy, K6EAW 



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I 



OCTOBER 1969 



11 



DX Corner 



Dave Mann, K2AGZ 
One Daniel Lane 

Kinnelont New Jersey 07405 



A number of letters have come in from 
WTW Certificate holders asking me to cor- 
rect errors in the standings hst published in 
March. While there isn*t a lot that we can do 
about the list already published, every effort 
will be made to see that future boo^oos are 
kept to a minimum. Bear with me and 1 am 
sure that it will all be straightened out. 

The cards that have been coming in show 
that 20 meters is still the favorite DX band. 
But there are signs of increased activity on 
the other bands. In the last few weeks Fve 
been pleased to see that cards have been 
submitted for awards on two and even three 
bands, I realize that many of you are chasing 
that elusive 300 mark on 20, but you should 
do a bit of listening on others. The results 
may prove gratifying. You will find that a 
great many DX stations will be eager to 
make schedules for the other bands as well, 
for they are also interested in contacts on 
more than one band. 

We have gotten used to thinking of DX in 
terms of 15-20 meters, principally. A com- 
mon complaint goes something like this, "I 
listened for a couple of hours on 10 meters 
the other night and the band was completely 
dead. There^s notliiiig doing there." 

Td like to suggest that you aim your 
antenna over the pole, about 345 degrees 
here in the East, and call CQ DX Pacific a 
few times, I don't want to make any rash 
predictions, but don't be surprised if you get 
answers from VR, J A, DU, XW8, VS6 and 
the like. It seems that a lot of people are 
listening at the same time without calling. So 
nobody answers! 

rd also like to encourage you to spend 
more time on 75-80 meters. There have been 
some very good openings lately, and would- 
n't it be nice to hang a certificate on the wail 
for this band? How about it? In line with 
rd like to suggest that if you have not 



gotten your copy of the 73 DX Handbook, 
you do so at your earliest convenience. 
Concerning my mention of 80 meters, there 
is a tremendous article in the Handbook on 
just this subject by John Devoid ere 0N4UN- 
It is complete in every detail. John really 
went all out on this one, I am confident that 
anyone who reads and absorbs it will acquire 
valuable information that will assist in gar- 
nering many DX contacts on this band* 

So I hope you will order this very 
important book soon. If you are interested 
in DX, I can assure you that it is the 
smartest three bucks you could spend, and 

worth many times the price, 

IVe been thinking— there are quite a few 

persons on the air who express anti-DX 
sentiments wliich often go unchallenged. 
There seems to be an idea going around that 
DX fever is an indication that somehow a 
ham is not a gentleman. It is a bit reminis- 
cent of the attitude of some of my dry fly, 
purist angler friends toward bait fishermen. 

ThiSj of course, is arrant nonsense. My 
only reason for bringing it up at all is that 
rd like some of these DX haters to try it for 
themselves, just once. Let them get into the 
competition for a piece of rare DX, over- 
coming their prejudice for just that brief 
recess, for just a taste of it. I'll warrant that 
a majority of them will be forced to concede 
that they've had the time of their lives. 

It's hard to admit one basic truth. All 
types of operation may flourish and flower 
without adversely affecting the organic well- 
being of ham radio as a whole. There are 
some who express fear for the hobby^s 
future unless everyone throws out his com- 
mercially buUt gear and builds his own. Silly, 
isn't it? Traffic men despise ragchewers. CW 
operators have contempt for phone men and 
vice versa* QRP enthusiasts loathe high 
powered boys. AM'ers call SSB*ers names^ 



12 



73 MAGAZINE 



p 



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Linear Linear Amplifier 

All amplifiers for SSB operation are called linear 
amplifiers. Frankly most of them are "so-called" 
linear. One amplifier, the 2K-3, stands out as a 
linear linear. You've heard the clean, sharp signals 
on the air. They shout "LINEAR LINEAR". 
As proof, study the oscilloscope displays published 
in a national amateur publication which reviewed 
the 2K in comparison with competitive amplifiers. 
Note the 2K*s classic straight slope bow-tie pattern 
in figure A as compared with the non-linear curv- 
ature of the competitive amplifier in figure B. 
Remember... the curvature of figure B means 
"splatter" on the band. Remember.. .the straight 
lines in figure A are the sharp, clean signals of the 




Figure A 




Figure B 



Wouldn't you really rather own a LINEAR linear 
than a "so-called" Unear? 

The 2K-3 (Console or desk model) $745.00 



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OCTOBER 1969 



13 



I 



and low band ops wouldn't spit on VHF*ers, 
And so it goes. The fact is, we all need each 
other, for the very life blood of ham radio is 
its broad diversification • We need all types of 
operations on all our frequencies. 

Since DX occupies the hearts and minds 
of a large segment of our ham population, I 
believe it's wrong for non-enthusiasts to 
express violent opprobrium on the air, as 
though they were talking about lepers. 

Many of our critics became sour on DX 
because they were not successful at it. They 
probably discovered that it was not as easy 
as they thought. Successful DX'ing is one of 
the most demanding facets of the game, 
calling for skill and patience, coupled with 
experience and maturity. It is not unusual to 
chase a specific country for years, and even 
then^ there is no guarantee of getting it, I 
have been after a few of them for a long 
time, and I scrutinize the bands for them 
almost every time I sit down to operate. This 
is the only way I know; there is no royal 
road to success. 

Many stations not engaged in DX chasing 

are operated in a fashion that would make 

the average DX'er cringe. They use mediocre 
antenna systems which simply could not cut 

the mustard. Their procedures would not 

begin to serve in DX*ing, for they still do not 

comprehend the importance of listening, 

listening, and listening some more. They are 

far too busy saying their "By GoUy*' and 

"Fine Business" for that. 

But this is only one man's opinion, Don^t 
take my word for it. If you want to get a 
taste of real excitement ^ put your signal and 
skill on the Une, and get into one of the 
pile-ups sometime. You may become frus- 
trated, that's for sure. But you wiU also find 
yourself developing a healthy respect for the 
skill and ability of the successful ones. 

We all recall the story of the completely 
outfitted fisherman, with all the fancy 
tackle, encountering the kid with the buggy 
whip, dime store hook and can of worms. 
The urchin has no fancy flies, no two 
hundred buck rod, no waders, no nothing. 
But he has a stringer full of fish, and the 
fancy dude with the high class equipment 
hasn*t a single trout. AU the kid has is plain 
old talent, that's all! There's a lesson there 
for the would-be DX'ers, 



Well, that*s all I intend to say on the 
subject. If you are against DXMom, and you 
have a feeling of superiority over the fools 
who participate in it, why, you go right 
aliead and do your rag-chewing or whatever. 
It will be your loss, I know. 

*i^L| a^j ^^ ^b 

^P* ^P ^m* ^k 

I worked an odd one the other evening on 
14 mhz CW. There was a huge pUe-up on the 
low end caUing LG5LG. He claimed to be 
operating from the Independent Territory of 
Morokuiien, on the Norwegian -Swedish fron- 
tier. He gave his QSL address as LA4YF, and 
asked for three IRC's. Well, though I have a 
very suspicious nature, I have a standard 
procedure for cases that seem phoney. I 
work *em first and ask questions afterward. 
So^ I got the contact^ hurdling the first 
obstacle, 

I must admit to curiosity, so I began to 
investigate Morokuiien. I consulted four of 
the best atlases ever printed, and there 
wasn*t a trace of the place in any of them. 
By this time I was pretty certain it had been 
a counterfeit call, used by some joker, trying 
to have some fun and excitement for him- 
self. 

Later that night, however, 1 hooked up 
with a Swedish ham who told me that there 
really is such a place, and that LG5LG is a 
legitimate operation. He further informed 
me that the IRC's are redeemed, and the 
funds are turned over to a crippled children's 
hospital and therapy center. Needless to say, 
I sent my QSL out the next morning. 

Both the SM and 1 agreed that it would 
be extremely unlikely that this LG5 would 
count for a new country, but today, when 
national boundaries and political status is in 
a constant state of flux, you can never teU, 
Incidentally, he also said that operations 
from Morokuiien are very, very rare, so there 
is not likely to be another operation there in 
a long while. So, if you hear him, don't turn 
up your nose. Get the contact, just in case* 
What have you got to lose? 

Gus has been making all sorts of stops in 
the Indian Ocean area, but so far there*s 
been nothing that would add to anybody's 
totals, either for WTW or DXCC. It's 
pleasant to work Gus anyway, of course, but 
it would sure be nice to hear him from some 
rare one, Sikkim, Bhutan, Tibet or maybe 



14 



73 MAGAZINE 



r 



BY land- Speaking of rare ones, Tra pre- 
paring a questionaire for publication in the 
near future ^ which will aid in determining 
the priority ratings of wanted countries. We 
will then be in a position to assist DXpedi- 
tioners to plan their itineraries. It's not that 
we spurn a country simply because we 
already have it in our logs, but all of us are 
itching to get a shot at some of the more 
elusive ones, Tm sure. Is there anyone who 
wouldn^t jump at the chance to work a ZA, 
YI^ F08 Clipperton, etc.? The questionaire 
will appear in a few months, and when you 

get your 73, don't forget to fiU the thing out 
and send it in, so we can tabulate some 
meaningful country priorities* 

The 1N2A that showed up on 20 Meters a 
short time ago has to be a phoney. The 
prefix is not assigned by ITU, and the Marco 
Island he purported to operate from is not 
listed in any of the four major atlases which 
I consulted, I cannot find any island in the 
area of coastal Peru which might be the one, 
for all those shown have well established 
names. Oddly enough^ the signals peaked at 
approximately the right beam heading. My 
best guess is that someone was operating 
someplace in Ecuador, Peru or Chile, 

I heard another lulu the other morning^ 
claiming to be in Basra, Iraq, He was using 
G3N0F/YI and called himself Mike, The 
only catch is^ G3N0F is Don McLean, a very 
good friend of mine in Yeovill, who's more 
interested in jazz recordings than in traveling 
for an oil company^ which this joker claimed 
to be doing. 

I simply can't understand the type of 
mentality which goes to the trouble of 
engineering a DX hoax. It's a lot of hard 
work; almost drudgery. And . . - for what? I 
think that most of these guys must suffer 
from vacant apartments in the upper story s. 

Here's something that's bothered me for a 
long time. You hook up with a German, 
Czech or Russian. He speaks the English 
language with an accent, that^'s for sure. But, 
have you ever noticed, as I have, that his 
grammar is perfect in most instances. Syn- 
tax, number, gender and case are used 
properly. He never says who when he means 
whom* He doesn't mix up imply and infer. 
He doesn't split infinitives either. Yet, Amer- 
ican amateurs, born and reared in this 



country J sometimes speak the most horren- 
dously poor English to be heard anywhere. 
It is doj^nright humiliating to hear some of 
the lingo that passes for English. As my 
friend W2NDK, Arthur Harris, says, "He 
don't speak so very many, but he doing the 
best what he are!" 

I heard a couple of lads on 20 the other 
night who were having a time for themselves. 
They kept reducing power to see how long 
the copy would hold up. The fellow in 
Australia was audible here in New Jersey 
when he was reporting a dc input of 500 
miliwatts, I lost the Ohio station at about 75 
watts, but the VK continued to read him. It 
was most interesting, I understood why the 
VK came through so well when he described 
his antenna. He was using a wire quad; 
eleven elements on a 1 50 foot boom. I can't 
even visualize an antenna like that. Brother, 
that's what you call an aerial and a half! 

During the course of the last year or so I 
have been QSL manager for Danny Willis, 
CT2AS. It is really surprising to see so many 
hams who are still unaware of the impor- 
tance of getting the date correct, and making 
sure that the contact is logged in CMT. 
There simply isn't enough time in which to 
go hunting through hundreds of log entries 
in order to find one. It^s the proverbial 
needle in the liaystack. Please, everybody, 
get into the habit of using Zulu time* 

We have finally gotten the new countries 
lists for WTW from the printer, and they are 
ready to be sent out to anyone who requests 
them. Remember, you will need one for 
each of the bands you intend to submit for, 
but they need not be sent in with your 
cards. You may transcribe the list on ordin- 
ary paper, typewritten, if possible, showing 
the contact and date. So long as this list is 
legible it wUl suffice. 

Here are the currently claimed WTW 
scores. Some of you have been inquiring 
about countries lists. They are in preparation 
and should be availably soon. All who have 
requests in for them will receive them as 
soon as they come off the press. 

It looks like we are close to our first 
WTW-300 certificate. Vd feel a lot better if 
there were some hot competition for this 
award. Many of you have evidently been 
lying "doggo" recently, for I have not been 





i 



OCTOBER 1969 



15 



getting too many revised claimed scores 
lately. How about pumping up those scores? 
Frankly, WTW is hurting from a drought of 
activity. There does not appear to be suf- 
ficient interest in the award at present, and 
the reasons for this may be many and varied. 
Not the least, I'm sure, is the removal of 
some of the frequencies formerly enjoyed by 
all of us. Rather than probe into those 
reasons, though, let's just say that we hope 
the inactivity is merely temporary, and that 
we can look forward to better conditions 
ahead. Tm pretty sure that if a rare one were 
to show up there would be a revival of 
interest. All we need is a Clipperton opera- 
tion; Tokelaus^ Chagos, Agalega, Kuria 
Muria, or the like^ and watch those grounded 
grid amplifiers start heating up- The Malpelo 
action recently showed that there*s still lots 
of life among the DX hounds. 

The Coast Guard has now revised its 
former opposition to operations on Navassa, 
They will now permit ham operations there 
during the two times a year that a Coast 
Guard vessel in in the vicinity. This is 
excellent news, for there are many who have 
expressed a strong desire to go there. So I 
think that we can all look forward to 
another shot at this goodie in the near 
future. 

WTW HONOR ROLL (claimed scores) 

7 mhz-CW: 

W4BYB 151 

W3WJD 100 

W8ZCK 100 

VE3BLU 105 (new certificate) 



14 mhz-CW: 




WB6NWW 


113 


K4CEB 


102 


W8EVZ 


102 


W4CRW 


101 


WA2DIG 


100 


K8IKB 


100 


WB6SHL 


100 


W9HFB 


100 


W50DJ 


100 


WB2TK0 


100 


WA9KQS 


100 


WIETV 


100 


K5BXG 


100 


K4ASU 


100 


WA6GLD 


100 


W2UGM 


100 


14 mhz-Phone: 




W6YMV 


150 


K2Q0U 


125 


WB2NSG 


122 


K4GX0 


120 



KISHN 

WISEB 

W4TRG 

WA40PW 

SV0WL 

W0SFU 

W3SEJ 

CN8FC 

VE3ELA 

VE6AKV 

K4VKW 

W60HU 

W8WAH 

WA0OAI 

21 mhz-CW: 

W40PM 

W0DAK 

WA9NSR 

WB2UDF 

VE6TP 

WA6GLD 

W0RRS 

WA90TH 

21 rrihz-Phone: 

W40PM 

WA5L0B 

W6MEM 

WA2FQG 

WAIEUV 

WA5DAJ 

W9NNC 

WB2RLK 

W8WRP 

W4SYL 

W2PV 

WIEED 

K5HYB 

W2VBJ 

K4VKW 

WB20B0 

K9PPX 

W6YMV 

WA4WTG 

WA0OAI 

WA8VFK 

28 mhz-Phone: 

WAS LOB 

W6MEM 

WA5DAJ 

WB2RLK 

W2PV 

W2VBJ 

WA7BPS 

W4GJ0 

W5YPX 



111 

110 
106 
105 
105 
104 
103 
103 
102 
102 
102 
101 
101 
101 



200 
07 
03 
00 
00 
00 
00 

100 



220 
62 
61 
55 
38 
30 
25 
10 
06 
06 
04 
03 
01 
01 
01 
01 

100 
00 
00 
00 
00 



50 
29 
17 
15 
106 
04 
02 
00 
00 



We are in need for check points in the 
1st, 4th and the 10th districts. Also any 
clubs on the continent of Europe, South 
America and Africa wanting to take on this 
job, please get in touch with me through the 
magazine or direct, if you would like to 
help. 

Here is a list of all current check points. 
We still need three more to fill out the roster 



16 



73 MAGAZINE 




Call 



State . 



3 years ZIP 
t year 



^^N^^ ^ ^ I^ ^^N^ M^ I^ ^ ^^^ ^ Il^ W 



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Radio is one of the greatest hobbies there 
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i 



I 



OCTOBER 1969 



17 



and I wish some clubs and groups would 
volunteer to complete our list. Meanwhile if 
your area is not covered, send cards directly 
here, at: 1 Daniel Lane, Kinnelon, NJ 
07405, along with $1.00 to cover handling 
and cost of certificate, etc. If you wish your 
cards to be returned via registered mailj etc., 
be sure to enclose enough money to cover 
same, otherwise they will be returned at the 
cheapest rate; hardly the safest method. 



1st District 



None (send cards here) 



2nd District Peninsula Amateur Radio Club 
Foot of 25th St., Veterans Park 

Bayonne, NJ 07002 

3id District Western Pennsylvania DX Society 
John F. Wojtkiewicz W3GJY 
1400 ChapUn St. 
Conway, PA 15027 

4th District None (send cards here) 

5th District Garland Amateur Radio Cluti 
2905 Sheridan Drive 
Garland, TX 75040 

6th District Orange County DX Club 
James N, Chavarria 
3311 Steams Drive 
Orange, CA 92666 

7th District Western Washington DX Club 
WiUiam H. Bennett W7PH0 
18549 Normandy Terrace S,W- 
Seattle, WA 98166 

8th District Straits Area Amateur Radio Club 

William Moss WA8AXF 
307 Grove Street 
Petoskey. Ml 49770 

9th District Montgomery County Amateur Radio 

Club 
Scott Millick K9PPX 

Litchfield^ IL 62056 

10th District None (send cards here) 

Canada (all) Edmon ton DX Club 
VE6GX, 12907 136th Ave. 
Edmonton, Alberta, Canada 

Oceania New Zealand Assn, of Radio Transmitters 

Jock White ZL2GX 
152 Lytton Road 
Gisborne, New Zealand 

South America Venezuela Amateur Radio Club 
PO Box 2285, Attention YV5CH0 
Caracas, Venezuela 

Vs you can see, we are badly in need of 
idditions to this list in Europe, Africa, 
Jouth America and Asia. We could also do 
¥ith one in Australia, Interested groups and 



clubs please contact me via 73 magazine or 
direct. 

I take parficular pleasure in announcing a 
welcome addition to our award. The Com* 
mittee has agreed that we should establish 
two new categories. Here is the rundown, 

MWTW, Mobile Worked the World, is 
awarded to mobile stations exclusively. The 
one bandone mode rule is bypassed for this 
category. All bands —all modes will count 
toward the certificate. The only stipulation 
is that any contact must be made with a 
mobile antenna. We will not honor any QSO 
known to have been made where a mobile 
rig was piped into a fixed station aerial, as is 
sometimes done on vacation trips, 

WTWM, Worked the Worid Mobile, is 
awarded to fixed stations for contacts with 
mobiles, including maritime and aeronaut- 
ical. In this category we will retain the one 
band-one mode rule. All other WTW rules 
will continue to apply, with respect to date 
of contact, etc. 

After some thought/ it has been decided 
that cards which may already have been 
submitted and counted toward an existing 
certificate, may be applied to the new 
MWTW award. If you decide to go for this 
certificate, you may re-submit any of them 
wliich might be eligible for inclusion. But, 
please make sure to note that they are 
re-submissions so that we have a record in 
your file. 

We don't have the new certificates 
printed for these awards as yet, but you may 
submit the cards now. We will process them 
now and notify you at once, sending the 
certificates as soon as we get them. Please 
send your entries to me, direct, as the check 
points have not yet been notifi^ of the new 
awards. Good luck to aU participants. 

We will not issue new certificates for 
credits above 200. Instead, we have designed 
an endorsement sticker, which is to be 
affixed to the original award. Any applicant 
for WTW-100 or WTW-200 will receive the 
certificate, and when he applies for 300 he 
will be awarded the endorsement. 

This will save us a great deal of trouble 
and expense^ and it will save you the cost of 
an additional display frame. Also, it wiU 
enable us to send you back your QSL cards 
plus the sticker in one mailing rather than 



8 



73 MAGAZINE 



two. It win also do away with the problem 
of mailing tubes, which, I swear to yon, is 
the biggest pain-in-t he-posterior I have ever 
encountered. You cannot buy less than a 
gross of the bloody things, and when you do 
get them you have to find adequate space to 
put them. And, they collect more dust than 
you could imagine, but worse than that, 
they seem to be a natural habitat for 
honey-mooning field mice, wasps, spiders, 
carpenter ants and other unattractive var- 
mits of varying descriptions. 

There may be a few recently issued 
certificates whose holders are not listed this 
time. They will be included in the next 
publication of the list. 

Next time we hope to have a report from 
Gus. Also may have some interesting dis- 
closures from a well known former DXpedi- 
tioner who will tell all about some of his 
past corner cutting. This promises to open 
up a whole can of beans, and is guaranteed 
to turn a few faces red. 

Next issue will include updated claimed 

scores, new certificates issued and order of 

standings. Don't forget about the new 

MWTW and WTWM. Vd Uke to see lots of 

applications in the mailbox. That's it for 

now. See you next month. 

. . . K2AGZ 



Try This One 

Try tiiis one on your friends and see how 
many will take the bait without giving it a 
second thought. The problem is: Your moni- 
tor scope has gone sour. The trace is very 
faint with the intensity control at maximum. 
You have checked the schematic and de- 
cided to measure the divider. According to 
the manual this point should be at -560 vdc 
in respect to the chassis. If you want to 
impose the least possible load on the circuit, 

do you use the 1000 volt range on your 
20,000 ohm per volt VOM or on your 
VTVM, with its 1 1 meg input? 

If you said the VTVM go directly to jail, 
do not pass go, do not collect $200, The cor- 
rect answer is the VOM, The VOM on the 
1000 volt rangex 20,000^2-20 megohms, or 
nearly double the input resistance of the 
VTVM and for this reason would load the 
circuit only H as much. 

. „ . BiU Turner WA0ABI 



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Name 






Address 






City 


state 


Zip 



I 



J 



OCTOBER 1969 



t9 



I 



Chuck Hines K6QKL 
86 IS Idlewood Drive SW 
Tacoma, WA 98498 



FET Chirver 






The Chirp er is an automatically keyed, 
crystal controlled, signal source which may 
be used to optimize the signal-to-noise ratio 
of a receiving converter* Homebrew or com- 
mercial, converters are a common thing 
around an amateur station. And, most of the 
VHF Tribe have read thru a jungle of 
esoterica dealing with low noise front ends, 
the velvet beauty of FET's on Two, noise 
generators and eternal truth, and how to 
copy 20 db below the noise by the selective 
use of Uquid helium. With a kind of re- 
lentless evolution converters have been 
getting better and better, noise figures be- 
come lower, and the prices of suitable front 
end devices are dropping by the hour. But 
when it comes to aligning these converters 
the scene is one of wretchedness. A black art 
at best, the job is taken up with an enduring 
combination of blunt instrument and myth. 
The latter have a certain charm. Are you 
convinced your converter is in top notch 
condition because you can *'hear noise" 
when you attach the antenna — or better 
yet, when you place a 50 ohm resistor across 
the input? Try putting a complete short 
across that same input. Shorts aren't much 
good as noise sources. You'll find the short 
gives about the same change in noise level as 
the 50 ohm termination. What has changed 
is the impedance the front end "sees". The 
same is partially true of the noise from the 
antenna. Neither is indicative of the 
performance of the converter. Peaking the 
system up for maximum on either a weak 
signal or on noise gets you nowhere. The 
diode noise generator which every VHF 
book of substance describes is a good and 
useful tool when used properly. The assump- 
tion is that everyone already knows full well 
how to use it and does so. Few in fact do. 

Vm sure you've read of it before in many 
places, but a little redundancy is in order. 
The noise with which you are concerned is 
the noise generated internally by the first 
tube, transistor, or other active device the 
signal encounters upon its arrival at your 
converter. By fiddling with the external 




reactances, adjusting the voltage and current 
and otherwise manipulating the things 
soldered to the device, one may minimize 
the internally generated noise. At the same 
time the reason the front end exists is to 
ampUfy the signal. One usually desires as 
much amplification possible, short of smoke 

and osciUatiOn, Minimum noise and maxi- 
mum amplification is the game. Though the 
two are not quite mutually exclusive a 
certain amount of compromise takes place. 
Thus, the signal to noise ratio. When aligning 
a converter's first stage every adjustment 
effects both signal and noise. Given a con- 
stant signal source coupled into the con- 
verter thru an appropriate impedance, the 
job is finished when the front end has been 
adjusted for the greatest difference between 
signal and noise of which it is capable. 

The Chirper is designed to help you do all 
this by letting you see what effect each 
adjustment has on both signal and noise. The 
TIS34 oscillates at a frequency controlled by 
the crystal With the constants shown, that 
can be anywhere between 8.2 and 36 MHz. 
The variable capacitor must be adjusted for 
resonance. It isn't particularily critical but 
its setting peaks the rf output at either the 
fundamental or some harmonic. For 6 
meters an 8.35 MHz crystal is used, A 9,0 
MHz rock will pin the meter when the 
Chirper is connected into a 2 meter con- 
verter. The Amidon^ toroid is wound with 
No. 30 enameled, 40 turns for the primary 
and 5 turns for the secondary. After it is 

1, 12033 Otsego St., N. Holiywood, CA 91607 



20 



73 MAGAZINE 




NRCI's compact new happening puts you on 
AM coverage of the 80 through 10 meter 
including built-in AC power supply and mon 
and you'll see this is the rig to stay with! 

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All-solid-state except for driver 
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Built-in RF speech clipper. 



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Wide- range fast attack /slow de- 
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Receive Vernier with separate 
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Suggested amateur net price, 
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For complete (and impressive) specifications and details, write: 

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NnCI 37 Washington St.. Melrose, Mass. 02176 



® 1969, National Radio Company, Inc. 



Internatfonal Marketing through: 
Ad Auriema, Inc., 85 Broad St., New York, N.Y. 10004 



AMIDON 
T-50-10 CORE 




Fig. 1. Schematic of the FET chirper. 

wound, spread the turns to fill the toroid 
and paint it with Q dope. The diode and 5 
pF coupling capacitor are connected with 
the shortest possible leads, the diode being 
grounded at the rf connector. The harmonic 
output is excellent and quite useable at 1200 



The oscillator is turned on and off by a 
multivibrator combination of unijunction 
and NPN transistor adapted from the G. E. 
Transistor Manual The rate at which the 
multivibrator cycles is determined by the 
large value capacitor, in this case 33 mF. The 
polarity of the capacitor is critical. Observe 
it. To increase the cycHng rate, decrease the 
capacitance; and, to decrease the rate, put in 
a larger value. Mine cycles a little under once 
per second. A value somewhere between 30 
and 40 mF should suit your needs. You are 
better off scrounging some odd value from a 
defunct computer board because of the 
tolerance problem. If it says 33.2 mF, its 
probably pretty close to that value. Other- 
wise you're dealing with tolerances of plus 
100% and minus 50% or something equally 
grotesque. The 50K pot determines the 
portion of the cycle during which the 
oscillator is On and is mislabeled rate on the 
Chirper shown. The HEP-310 is generally 
available and inexpensive. Other un^junc- 
tions were not tried. On the other hand 
almost any NPN of reasonable quality will 
work in place of the 2N7I8. A number of 
2N388 and 2N3478's were tried and be- 
haved well. It's a good place to use tho§e 
transistors youVe replaced with FET's.'Use 
something with a Beta of 50 or better for 
best results. The 5100 ohm resistor in series 
with the pot is for current limiting. It's 
deletion will increase battery drain with no 
incyease in Chirper performance. Normal 



current from the 9 volt battery is around 5 
mA. 

Construction is non-critical and pretty 
much a matter of taste. Mine is built on a 
piece of vector-board and mounted in a 
Suzurando^ box, model M-IN. It measures 
3^4 X 2 X 4" and there is still room inside 
for additions. It sells for 330 yen, about 92c. 
A slide switch is used to turn the power on 
and off. Paint one well of the slide switch 
with red paint - Tester's Pla, a model plastic 
paint, is good - and the switch will indicate 
its position. Red for On and black for Off. 
It saves batteries. Check your work and the 
polarity of the large capacitor. Re-check the 
connections to all the semi-conductors. With 
four different kinds of devices things can 
become confused. Set the pot to the middle 
of its range. Insert a crystal in the socket. 
Connect the Chirper to your converter, turn 
the switch on and adjust the variable capaci- 
tor for the highest reading on your S-meter. 
The oscillator will turn on and off. Varying 
the pot will extend or diminish the amount 
of time the oscillator is on. Whatever you 
do, don 't connect the chirper to an external 
antenna. The harmonic content is high and 
even at this power level is sufficient to cause 
severe interference to television receivers 
within a two block radius, 

I VTVfm \ 



CHtflPER 



C 



ifTtwATnn 



CONVERTER 







Fig, 2. Test set-up for converter alignment. 

For converter ahgnment, the test set-up is 
illustrated in Fig. 2. The Chirper is fed to the 
converter thru an attenuator for two 
reasons. First, the power output of the 
Chirper is too high on six and two. You 
don't want to align with a forty over nine 
signal. Something around S-5 to S-7 is 
desired. Second, the attenuator maintains a 
50 ohm termination for the converter. A 
converter cannot be aligned with a floating 
input impedance. Fixed and variable attenu- 
ators of excellent quahty are available thru 
surplus and homebrew data is available. See 
7S, January 67, p. 40 for one that will do 
the job. Turn the receiver avc off. The 
read-out options are diverse. The best is 
pr<>bably a scope connected to the if. A 
vtvm can be used, connected to the audio 
output. And, the S-meter can be used with 
the avc on fast. This will vary with the 

2.Suzurando, 1-10-11 Sotokanda Cbiyodaku, Tokyo 



22 



73 MAGAZINE 




1 



receiver and it*s particular time constants. 
What needs to be avoided is avc pumping 
that interferes with your readings. 

Turn the Chirper on, adjust the attenua- 
tor for a convenient signal level. When the 
oscillator is on, you're reading signal When 
the oscillator is off, you^re reading noise (on 
the scope, vtvm, S-meter, etc.). As you make 
adjustments on your converter, observe the 
effect on both signal and noise. Adjust for 
the greatest difference between the two. 
Turn the Chirper off and re-check the 
converter neutralization. If necessary, re- 
neutralize the converter and go thru the 
whole thing again. Talking about it makes it 
seem somewhat complex. It really isn't and 
the whole business won't take long once 
youVe done it. It will become quickly 
apparent that highest signal level and lowest 
noise level do not coincide. You can vary the 
bias^ voltage, etc., and observe the effects of 
each on the signaHo-noise relationship. You 
can^ in short, optimize your converter's 
performance, 

A number of things can be done with the 
Chirper, There is room in the box to build 
another oscillator section connected to the 
transistor coUector, operating in parallel and 
simultaneous with the first oscillator- By 
appropriate choice of crystal and attenua- 
tion, both signals can be introduced into the 
converter in order to adjust the mixer for 
minimum cross modulation- 

Or, instead of using an oscillator at all, 
you can use the switching section of the 
Chirper to key a noise generator on and off. 
This has a certain attraction where an 
integrating network is used prior to a vtvm. 
In this case noise is used as a signal. 

In spite of it*s name, the Chirper is 

remarkably stable. Chirp becomes apparent 

from two meters or so, but is no problem. 

Build one and take the myths out of your 

converter* 

, . . K6QKL 



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CONVERTER 




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I 



OCTOBER 1969 



23 



The 




W. Edmund Hood W2FEZ 
223 Pullman Ave. 
Rochester NY 14615 




on 





As long as there have been radio 
amateurs, hams have been interested in the 
telephone system and sought ways to 
integrate it into ham communications. The 
worth of this idea needs no explaining. With 
their great tradition of pubhc service and 
emergency work, ham operators have time 
and again proven their skill and efficiency in 
time of need. Nonetheless, in order to be a 
truly effective service, ham radio should be 
ready, whenever necessary, to utilize any 
and all media for communications. In spite 
of the fact that the two services grew up 
together, comparatively little data of any 
value is available for our use. Therefore the 
ham is often inclined to experiment on his 
own. This clandestine activity can have 
tragic results in the form of angry telephone 
officials, and, in some cases, can produce 
real damage to the telephone system, to say 
nothing of the expensive ham equipment. 

In all fairness to the telephone people, it 
should be pointed out that a service so 
widespread as theirs can become night- 
marishly complex. Take the telephone found 
in the average home. It's a lot more intricate 
than the cheap field phones they used to sell 
in the Radio Shack, 

The diagram is the result of the dissection 
of a surplus telephone, rather than any 
revelation by Mr. Bell. With the receiver 
hung up, S4 and S5 are held open* A strong 
ac signal can pass through C2 and ring the 
bell J but the rest of the instrument is 
disconnected. When you pick up the phone, 
S4 and S5 close. As you start to dial, SI 



opens disconnecting the earphone, and S2 
closes. As the dial return s^ S3 opens and 
closes pulsing the hne. You can follow the 
circuit from the red lead through S2, which 
remains closed until the dial reaches its rest 
position, then through the pulser, S3, 
through S5 (closed because the receiver is 
up) and out via the green lead. A dc voltage 
is present on the line, and the closing of S3 
shorts it out, producing pulses which are 
sensed by the stepping relays at the central 
office. 

After you have finished diaUng, SI and 
S3 are closed, and S2 is open. The dc voltage 
now reaches the mike from the green lead, 
through S5 and S3, through the mike^ then 
into the auto transformer, L, where it is 
stepped up and sent out over the line. The 



PHO 




yic, 






< 
S 



r y^ 



^B2 nc 



Fig. 1, Diagram of a run-of-the-mill Bell tele 
phonQ, 



24 



73 MAGAZINE 





capacitor, CI blocks dc from the auto- 
transformer. 

The dc voltage on the line is in the order 
of 48 volts when it leaves the exchange, but 
can be considerably reduced by the time it 
reaches the subscriber. Sufficient tolerance is 
built into the system to aUow a wide 
variation. The signal which rings the bell is a 
20 hz. The voltage of the ac is 48 volts, but 
since it is superimposed on the dc, it can 
sum up to a total of 96 v. The dial tone 
varies from exchange to exchange. Anything 
that will make a sound wiQ do. 

A line from the exchange to the sub- 
scriber is called a loop. The overall im- 
pedance can range from 900 ohms to about 
1,5 k,5 although they like to shoot for a 
happy medium of 1.2 k. Since the sub- 
scriber's telephone is midway around the 
loop, it looks into an impedance of around 
600 ohms, and this value is the standard 
value used by radio stations in a remote 
broadcast loop. The frequency bandpass for 
conversational subscribers is 300 to 3k hz. 
This has proven most effective for trans- 
mission of speech with the highest intelligi- 
bility: Broadcast loops come in several 
classes- One has a passband essentially the 
same as a standard telephone loop. This class 
is used most often for sports and newscasts- 
The class of loop used for disc Jocky type 
programs, where some transmission of music 
is required, passes up to 8 khz,, and finally, 
FM stations occasionally use the most ex- 
pensive class with a full audio passband. 
(With very few exceptions, AM broadcast 
stations have an audio bandwidth limiting at 
6 khz.) 

Audio levels for the telephone system are 
centered around a reference (O db) of 1 
milliwatt across a 600 ohm load. Broadcast 
loops generally hold their audio levels at to 
+6 db. Home subscribers have no engineer to 
watch a level meter, and so it is difficult to 
pin down the audio level. Bell system 
engineers have no way of knowing whether 
the user will be a love-sick bobby-soxer or an 
eight-year-old telling grandpa about the fish 
he just caught. These represent two extremes 
for audio level. For design purposes, they try 
to consider the average of all voltage levels 
over a three-second period at -12 db. Using 
this figure as a design center, they are at 
least able to minimize crosstalk between 
lines. 

When the receiver is lifted, and switches 
S4 and S5 close, a dc path is closed for the 
48 volts on the line. The resultant current 



closes a relay in the central exchange which 
connects you into an available line to dial, 
and isolates your phone from incoming calls. 
As you dial, the pulser, S3, produces a series 
of brief shorts, so far as your telephone is 
concerned. At the exchange, however, these 
"shorts" are seen as a series of current 
pulses. These pulses go into a device similar 
to a stepping relay, which counts the pulses 
and connects your phone to a set of contacts 
determined by the first digit you dialed. 
Each set of contacts is connected to a 
second stepping relay. The relay on the set 
of contacts corresponding to your first digit 
is pulsed when you dial the second digit. 
This connects you to a third stepping relay, 
and so on until you have dialed the full 
number. The final position of the last relay 
is connected to the telephone you are 
calling. The presence of your signal trying to 
reach this number closes another relay which 
sets the ringing mechanism into motion. 

The ringing mechanism sends a 48 volt ac 
pulse into the line you are calling. This pulse 
passes through the blocking capacitor and 
rings the bell. When that line is picked up, its 
current censor closes making the final 
connection. The ring pulse, by the way^ is 
one of two possible signals, depending on 
the service you have. Both are based on a 
5 -second cycle, A **long" ring is on for one 
third of the time and off two thirds. Some 
phones ring in a sequence of two short rings, 
each one sixth of the time with one sixth 
interval between them, and then pause for 
one half of the time. 



1209 



1336 



1477 



1633 



S9T 



O — — — O 



770 



es2 



94» 





Fig. 2. Touch-tone switching matrix. 

The touch-tone system, now available in 
some localities, sends a combination of two 
audio tones down the line which trip a 
frequency sensitive relay. From there the 
sequence is similar to the dial system except 
that frequency sensitive relays are used 



1 



OCTOBER 1969 



25 



instead of the stepping relays. The combina- 
tions are given in the matrix shown here. 
The tones for any given digit are determined 
by the intersection of the tone-lines at which 
the button is located. For example, the digit, 
4, would send out a combination of 770 hz^ 
and 1209 hz. The two figures in the bottom 
row, # and * are only available on certain 

military and industrial phones. The 941 hz 
signal only appears in a standard phone 
when the zero button is pressed. The fourth 
vertical row (1633 hz) is not used at present, 
except in certain data-transraission systems. 
For the most part, it is reserved for further 
expansion. 

The descriptions given so far are a very 
simplified version of what goes on when you 
make a phone call. Multiply this by a 
theoretical ten million possible number 
combinations and you can get a slight idea 
of the nightmarish complexity of the 
system. One small goof by some character 
who doesn*t quite know what he is doing, 
reflecting back through the central ex- 
change, can upset the whole applecart- The 
telephone system, being an emergency 
service, is therefore protected by federal and 
state laws against any tampering that might 
disrupt the service or invade anybody's 
privacy. As one telephone engineer explained 
to me, **It*s not that we're trying to 
monopolize the equipment, but unless we 
know what is hung on that line, we can't do 
our job. Also, you're paying for the service, 
not the lines. If you put on an extension 
phone of your own, you're taking service 
that you're not paying for/* 

Over the years, Amateur Radio has 
proven its worth time and again in emer- 
gencies. When disaster strikes, it is good that 
all services can work together and combine 
all available facilities for the public good. 
Now the telephone company cannot and 

does not object to the infinitesimal amount 
of competition offered by hams chatting 

long distance over the air. But when we use 
their own facilities to phone-patch a pleasure 
call in competition with them, you've got to 
admit that's getting a bit dirty. While the 
telephone company won't go broke from the 
loss of an occasional service charge, the 
reputation of Amateur Radio is far too 
valuable to attow it to be cheapened by so 
small a thing as that. What 1 have told about 
the telephone system so far, as well as what I 
am about to tell, is not by any means being 
revealed so that my brother hams can 
outsmart Mr. Bell, but rather, if the need 
should ever arise ^ that they might have* the 



know-how necessary to make use of every 
available facihty for the good of their 
fellow-men. In such a case as that, even the 
strictest of the telephone people would very 
probably go along with you- And so I clear 
my conscience with the reminder that you 
receive with this knowledge a responsibility 
to use it only to the greater credit of the 
fraternity. One clown can ruin things for all 
of us. 

When it comes to coupling into a tele- 
phone line with equipment of other than 
Bell System design, we should look first at 
the broadcast stations. They do this sort of 
thing on a far larger scale than any other 
telephone company customer* In the broad- 
cast industry the most common method is 
transformer coupling. Broadcast loops are 
generally treated as if they were 600 ohm 
balanced Unes. Therefore, any 600 ohm 
transformer winding should offer a decent 
match. It is worth noting that the telephone 
people sometimes clear their lines with a 
high-power surge at around 500 volts dc- A 
blocking capacitor of sufficient capacity 
with a good high voltage rating can save you 
a lot of grief. Remember also that the 600 
ohm winding only looks like 600 ohms if the 
other winding is properly matched. If the 
transformer has, for instance^ a 10 K 
primary and a 600 ohm secondary, it must 
have a 10 K load across the primary. Also, 
some means should be provided to insure 
that the audio level does not exceed about 
db, even if it means buying a meter. For 
those who want to stay on the good side of 
Mr, Bell, the telephone company makes 
available in many places a coupling trans- 
former together with a telephone fitted to 
automatically remove it from the line when 
the receiver is down. After a $5 installation 
charge, it only adds 50c a month to your 
bill. 

If you intend to record off the phone, 
remember that the law requires that a 
'*beep^' be sounded on the line, or that the 
other party know right from the start that a 
record is being made. 

There are a number of low-priced 
induction pickups on the market which 
work by detecting the magnetic field of the 
auto transformer or of the earphone. These 
not only work, but they will also feed a 
signal into the line if the level is high 
enough. However, unless the other party is 
aware of it from the begiiming, it may prove 
to be a violation of the federal wiretap 
laws, , 

The diagram shows aU the necessary 



26 



73 MAGAZINE 




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Fig. 3, Isolating circuit for coupling to 
phone line, 

elements for coupling into or out of a 
telephone line. The three resistors may be 
entirely unnecessary if the primary winding 
of the transformer matches exactly the 
circuit feeding it. Using realistic values, 
however, it's perfectly possible to have a 20 
K transformer and a 1 meg recorder or 
modulator input. If such were the case, R2 
would have to equal the transformer im- 
pedance, (in this instance, 20K) Rl in series 
with R2 should equal the apparatus im- 
pedance (1 meg.) The values are different 
enough that Rl could be 1 meg, and the 
series combination of Rl and R2 would not 
make that much difference. With this 
arrangement, R3 could be left out. This 
could take audio off the line quite effective- 
ly, but it would have a 50: 1 attenuation if 
you tried to feed voltage in. Much better to 
properly select your transformer in the first 



place. Taking another case, suppose you 
were using the same transformer as before, 
but feeding it from a 10 K source. R2 would 
stOl match the transformer, R3 would match 
the source (10 K), Rl would, have to be 
about 10 times the larger of the other two 
(in the case, 200 K). If the apparatus had an 
impedance equal to the primary impedance 
of the transformer, you could then leave out 
all three resistors and there would be no 

attenuation. The meter, M 1 is a standard VU 
or decibel meter to ensure that the lever 
going out onto the hne were the same as that 
coming in (no more than db). The 
capacitor serves to block against any high- 
power dc surge, and is picked so that the Xc 
is about 1/10 that of the line, I have given 
enough information for the ham who is 
reasonably proficient in the art to quickly 
calculate the proper values to meet his 
needs. In the interests of Amateur Radio, 
and also in the interests of the reader, if you 
cannot figure out the proper values with the 
information given here, I'd say don't mess 
with the line. Unless you really know your 
stuff, it's better for you to buy a pickup coil 
or pay the extra few bucks to the phone 
company for one of their couplers. . W2FEZ 






OCTOBER 1969 



27 



Dave Mann, K2AGZ 
One Daniel Lane 

Kinnelon, New Jersey 07405 



Leaky Lines 



I've been lambasting the editorialist of QST for 

quite a while, on the basis of his ill-conceived piece 

last February concerning freedom of speech. After 

a couple of recent experiences, 1 have revised 

slightly my stated views on this matter, and would 

like to outline my current ideas on the subject 
You will recall that I opposed the notion that 

freedom of expression should be censored in any 

way* I said then that mature and intelligent people 

are capable of discussing anything under the sun 

without becoming emotional or insulting- 1 still 

feel this to be valid. Unfortunately, 1 did not take 

into account the fact that there are some who are 

not all that intelligent. 1 neglected to remember 

that there are people who will go out of their way, 

and seek deliberately to hurt, out of intolerance, 

bigotry, envy, or some fancied grievance* 

There are many malcontents in this world, and 
we have our fair share of them in Amateur Radio, 
There are bullies, misfits, paranoids, and a whole 
range of peculiar types who are not prepared to 
maintain that degree of dispassionate detachment 
which would permit discussion minus any violent 
verbal abuse. The very existence of this group casts 
some skepticism into my mind now, about the 
wisdom of my words; I have misgivings. 

It isn^t proper, after all, to steer clear of foul 
language, if I'm going to turn right around and 
backbite some other ham. I may never utter a 
sacrilege, yet I may get away with slander, libel or 1 
may bear false witness. Though 1 may avoid highly 
charged questions and pohtical controversy, I may 
indulge in hypocrisy of the vilest kind. 

There seems to be some idea that if a guy waves 
Old Glory and says he believes in the sanctity of 
motherhood and the home, he is then perfectly 
free to go on the air and express all kinds of 
poison J without fear of retribution- He can say 
anything, (so long as he doesn't cuss,) about 
another race, creed or color. He has only to avoid 
foul language, treason and sedition, heresy or 
irreverence, and he is witiiin bounds. 

I don't mean to suggest that we should not 
express dislike or disapproval. But, if you feel that 
someone is an unmitigated scoundrel or a plain 
louse, don't tell some third party about it on the 
air. it sounds horrible. Put it in a letter to him, or 
call him on the phone, and tell him. Or better yet, 
try to ignore the whole thing, and save yourself an 
ulcer. We'll all be better off 

Apropos this question of contempt for others, I 
wonder if youVe seen some "letters to the editor*' 



from some of the younger hams. Fm getting a bit 
fed up with characters who automatically classify 
everyone over thirty an old fogey- They tend to 
put their age alongside their signature, as if to 
proclaim, "Look what a bright and precocious 
child 1 am* " 

They say we aren't keeping up with electronics, 
and call us a flock of doddering morons. What a 
crock of sophomoric sassafras! There are all sorts 
of persuasions in ham radio* But 1 warrant that the 
very first thing that attracted almost all of them» 
like almost all of us* was the ability to communis 
cate; that's the name of the game. Theory, design, 
research, construction and other technical facets 
almost invariably are a later development- 
Why does a teen-age kid presume to tell his 
elders that they have no right to indulge their own 
particular desires and aspirations? Are only the 
young entitled to **do their own thing?" How do 
some people arrive at the startUng conclusion that 
anyone who does not share their standards is 
somehow unworthy? Where is tlie justification for 

this canard? 

This hobby is all things to all hams, and if some 
of these child prodigies don't like it, perhaps they 
should forsake ham radio and cultivate astro-phy- 
sics, brain surgery or some other field wherein they 
may breathe the highly rarified air of genius* 

I resent any implication that everybody who 
has achieved adulthood is a doddering, senile cretin 
who once passed a test, and has been stagnating 
and vegetating ever since. Perhaps we have lost 
some of our bounce, to be sure; that's Ufe. But 
there is one thing we like to think: we try to get 
along. We try not to be rude and discourteous to 
others, most of us. And, with few exceptions, we 
do not treat our ham colleagues with contempt and 
disdain. 

I*d love to be around to hear what some of 

these 'Vo^'^g Turks'* wUl say, some fifteen or 

twenty years hence, when some college punk, still 

wet behind the ears, calls them dead wood, and 

says they ought to '^shape up or ship out." 

* * 

First **beisbol.'* Then motion pictures and TV. 
Then the motorcar and airplane. Then moveable 
type, penicillin, radio and the carburetor. Oh yes, 
pity poor Robert Fulton and John Fitch; The 
Russians also invented the steamboat; or didn't 
you know that? WImt wiU they claim next? This 
reminds me of the old Gershwin song which went 
something like, but not precisely like this: 



28 



73 MAGAZINE 




They all laughed at Ivan Tomashevski 

When he said the world was round, 

They all laughed when Popovich recorded sound, 

They all laughed at Vronski and Polonski 

When they said that man could fly, 

They told KazuUski wireless was the bull-ski 

That^s the same old cry„...etc, 

I'd like to say a few kind words about SWL's. 
Not so much extravagant praise, but merely some 
recognition for the impulse behind the cards we 
sometimes get via the bureaus, FVe noticed that in 
addition to the infoimation they convey, some- 
times surprisingly comprehansjve with respect to 
conditions, propagation, and so forth, these people 
often display marked ability to copy code. Some- 
how it makes all the little carping complaints of 
the anti-CW proponents seem a bit unworthy. The 
hams who propose dispensing with the code as a 
tequisite for a license should devote some thought 
to this. The SWL wants to accumulate QSL cards 
from hams. He therefore sets about learning how 
to copy CW. There is no requirement that he do 
this. The achievement is its own reward. He has a 
goalj and this provides him with the necessiiry 
incentive. How then, can hams indulge themselves 
and abandon themselves to inertia and indolence, 
bemoaning their misfortune at having to meet code 
^standards, at the same time knowing that non-hams 
are beating them at their own game? 

I hope the time will never come when CW is 
done away with* Not only is it an efficient mode of 
communication, but a time-hallowed and tradit- 
ional part of our historical development* Many a 
golden chapter in the shining ciironicle of Amateur 
Radio would never have been written but for this, 
our first and most venerable method of transmit- 
ting radio signals. 

* * 

Remember how Charlie CorreU used to answer 
the phone? "Hello. Dis is de Fresh Air Taxicab 
Company. Andrew H, Brown, president, speakin\" 
Then came the sultry voice of the temptress, 
Madame Queen. "Hello, Andy," Andy^s tone of 
voice would change completely. "Heeeee-lUoooo," 
he would drooL 

I'm always reminded of this Amos *n Andy bit, 
whenever I hear the following phenomenon. 

A flock of guys are on the air, yapping about 
this and that; everything in general, and nothing in 
particular. Lots of kidding; references to graying 
hair or baldness, false teeth, and bulging waistlines, 
There^s talk about grandchildren, mobile homes in 
Florida, and moaning over little aches and pains, 
bursitis and lumbago. In short, from all indications 
these gents are certainly well within the category 
of middle age, and perhaps just a teensy-weensy bit 
older* 

All of a sudden a female voice is heard, 'way off 
in the distance, just about a smidgeon above the 
noise leveL Immediately these elderly parties are 
galvanized into a strange and wonderful meta- 
morphosis. In one fell swoop they not only 
develop super-acute hearing, but they seem to shed 
the accumulated years as a snake molts his skin* 
They revert to virile rooster-hood in an instant, and 



they become a gaggle of contending tomcats, 
serenading and caterw^auling to some feline para- 
mour from the backyard fence. They fall all over 
themselves in a spirited competition for the lady*s 
attention. From the sound of the response to this 
tomatoe, you would think she was Raquel Welch, 
Brigitte Bardot and Sophia Loren, all rolled into 
one. 

Next time you hear a YL breaker^ pay particu- 
lar attention to the atavism of all the old gaffers, 
and see if you don't get a great kick out of it. It's 
more fun than monkey gland extract, or a hor- 
mone injection, and who knows? It might just be 
the answer to the growing problem of geriatrics, 
There*s nothing like a little old fashioned S - X to 
stimulate some life in the old bones, right? 

FAMILIAR SOUNDS DEPARTMENT 

"Hello, CQ, CQ, CQ, from K2AGZ. Kilo two 

Alpha Golf Zulu calling CQ and standing by." 

"K2AGZ. K2.,. „. Z- This is K Baker, 

wheeeeeeeeeeeeeeeeee."*'QRZ, QRZ, QRZ, The 
station calling K2AGZ, please try again. QRM took 
you out. This is K2AGZ standing by for you." 

'*K2AG*-...„this is KR7 Whhheeeeeeeeee, 

Hello test, one two three four four three two 

one, Whhhhheeeeeeee squawk, splatter, squeak, 
crunch, bang, clang, crash, @t $%!&*() testing, 
testing, heeeeelllllllllloooooooooo test," 

'^KR7 question mark. KR7 question mark, this 
is Kilo two America Germany Zanzibar. I'm not 
quite getting your caU, old man, There*s heavy 
QRM, would you try it one more time please? 
Over/' 

'*Heeeeeeelllllllllloooooooooo, test* 
BBBBbbbbbZZZzzz, RRRRrrrrRRRRRrrrrr. Burp, 
wah-wah-wah, tweet tweet tweet tweet. Whistle, 
tweed le-dee-dee. Hallllooooo, test is anybody 
using this frequency?" 

"Nobody is using it. Go ahead, old man. You're 
a real nice fellow. K2AGZ clear and QRT." * * * 

In keeping with my generally iconoclastic 
attitudes, I'd like to give the "back o' me hand" to 
all these self-appointed watchdogs who seem to 
have proliferated recently on the bands. These 
screwballs* of course, did not just appear out of 
nowhere. They were spawned, in my view, by a 
recent editorial in a certain magazine which saw fit 
to open a whole can of beans about self-policing 
ourselves. 

Now, there's nothing new about this. Indeed, 
we have been discussing it for years. In fact^ it is 
the number one subject of the speech made by the 
Director of any given section, at the annual roast 
beef dinner of tlie Radio Club, But this time it was 
a bit different. For the very first time, someone 
came out in print, favoring the vitiation of one of 
our basic Constitutional privileges. Freedom of 
Speech. But Freedom of Speech is like pregnancy 
or death. There *s no such thing as a little bit of it. 
You either have it or you haven't! 

A typewriter is Like a gun* It will shoot 
anything you point it at. The man behind it must 
exercise good judgment at all times. In this 



I 



OCTOBER 1969 



29 



particular case the man behind the typewriter* 
obsessed with his own brilliance and wit, having to 
come up with a column about something or other* 
allowed himself to make an error of judgment . He 
exhumed this moldy fig from his mildewing trunk 
of ideas, never reckoning that it might raise a 
stench. And he underestimated the common sense 
of the readership! 

For years and years hardly anyone ever took 
issue with the pronunciamentos which came down 
from New Mount Sinai, Connecticut 0611 L Sacred 
cows, like other ruminants, become so absorbed in 
the chewing of their cuds that they develop total 
obliviousness to their surroundings; a sort of 
self-mesmerism. But in today's world things are 
different. There are no longer any sacred cows. Or^ 
if there are, they simply are not venerated any 
more. Poor old Hirohito celebrated his birthday 
the other day, and it rated three lines on page 27 
of the Paterson Evening News, 'When Mr. H, H, 
Humphrey crossed the street in St. Paul, a cab 
driver honked his horn and snarled at him, and two 
elderly Republican ladies made a rude gesture. Sic 
transit gloria mundi! 

The Editor never considered that this piece 
would provoke a deluge of protest Who woiilda 
thunk it? Wonder of wonders? from the Sanctum 
Sanctorum an encyclical had been pronounced, yet 
it was not accepted unquestioningly as dogma. This 
was decidedly not the reaction he had anticipated. 

So in the next issue but one, along with 

some of the letters of objection, the Editor wrote 
some minor retractions and statements of clarifica- 
tion, which sounded, for all the world, like 

# 

backtracking. He had to, for clearly, the natives 
were restless. To the everlasting credit of amateur 
radio, people who rarely expressed any opinions at 
alL wrote articulate, intelligent, and even brilliant 
denunciations of this attempt to stifle free speech 
on the bands. 

Of course, there were some who agreed with 
the editorial. I have heard a few of them^ anony* 
mously playing "vigilante" on the air, taking issue 
with those with whom they disagree. Mostly they 
concern themselves with an occasional hell or 
damn. One of these persons is a confirmed addict 
to the use of '^By Golly" and ''Jiminy Cricket". 

Consulting my Partridge *s Dictionary of Slang, I 
came up with the following. By Gosh, By Golly 
and By Gum are expletive substitutes for the Name 
of the Deity. Strange to say, the mild expressions. 
Goodness Gracious and Doggone It are similarly 
derived* Since one of the Ten Commandments 
expressly forbids taking the Name of the Lord in 
vain^ somebody devised this method of cussing 
without actually being profane. Semantically 
speaking, however, the changed words do not 
change the substance or context; it's still swearing, 

Jiminy Cricket, Jumpin' Catfish^ Gee Whiz, 
Criminy and Cripes, are all derived from the Name 
of the Saviour, and their use is every bit as 
objectionable as would be the use of His Name, as 
innocently as they sound! 

Shucks, Pshaw, Shoot and others beginning 
with the consonantal diphthong "sh" are all meant 



to take the place of that nasty pejorative which 
refers to a certain biological function, the less said 
about which, the better. In this group is included 
the non sequitur, horsefeathers. 

Fudge and Phooey I leave to your imagination; 
this is a family type publication! 

I hesitate to speculate upon the derivation of 
things like TU be hornswoggled, or 111 be jiggered. 
But drat it, darn it, what the heck, and son of a 
gun are perfectly obvious to anyone with half an 
ear for sounds. I did not investigate either, into 
nifty, to get one's wind up, or the often used 
bodacious. 

If you are interested in just how hairy tliis 
question of linguistics can get, just try using the 
terms, slowpoke or bugger, wliile talking to a 
Britisher. You're likely to get your head handed to 
you. 

Well, what Pve been driving at is this. I would 
far rather hear someone say an occasional hell or 
damn than some of those overdone cliches which 
are accepted as innocent. There is no valid reason 
for a Cripes man to look down his nose at a Hell's 
Fire man. If the latter were to say BrimstDne and 
Ashes, or Perdition, it would not even get a raised 
eyebrow in polite society - Yet, the meaning is 
exactly the same. 

Let's face it; language belongs to those who use 
it, not to those who would like to regulate and 
limit it. And if you really want to get down to 
cases, it's not really the words these people are 
gunning for. They are trying to shoot down the 
ideas that are expressed by words. And ultimately 
to take away your right and mine to express them. 

^^ i^p ^k 

Would someone please explain 

Why the hardest thing in the world to get is an 
honest audio report. 

Why the next hardest thing to get is a rotator 
that doesn't quit during the worst blizzard of the 
winter. 

Where to find a ham who is satisfied with your 
S-Meter. 

Why the guy with the most atrocious banana- 
boat swing is the most zealous opponent of 
electronic keyers, on the grounds that they rob 
fists of individuality- 

Why your XYL insists upon using the vacuum 
when the signals are marginal. 

Why certain hams send CQ at a swifter rate 
than their ability to copy, and when you match 
their sending speed exactly, they request you to 
QRS, 

Why some ignoramus breaks, uninvited, into 
your discussion without identifying, and demands, 
"Why don't youse guys stop talkin' about all that 
political crap? Dontcha know that controversial 
stuff is outa bounds? What are ya anyway, a bunch 
o^ commies?" 

Why the lid who starts calling CQ on your 
frequency always says to tlie guy he hooks up 
with, "We're getting QRMM. Boy, I dunno what's 
happening nowadays on the ham bands. There's 
just no courtesy anymore." But don't get me 
wrong-...,... J love Amateur Radio! K2AGZ 



30 



73 MAGAZINE 



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The accompanying diagram is an auto- 
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input at the antenna of 1 uv and the 
maximum if response for signals greater than 
1000 uv. Since the choice of photo cell PR 
governs the actual extremes I shall not quote 
any figures. 







VI emits Ught and is controlled by the 
AVC 

Photo cell PR is in series with the Q 
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condition and therefore continually adjusts 
to the signal tuned. It is quite effective for 
weak signals, giving a better signal/noise 
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The patent for this device was granted Jan 
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In the actual unit many cells seeing 
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Since the idea is simple, I will say no 
more. 

Roderick A. Johnson, KIPIZ 



I 



I 
I 



73 MAGAZINE 



31 



mm 



Scop 



e 



George Wilson WlOU* 
318 Fisher Street 
Walpole,MA 02081 




rator 



Introduction 

Instrumentation for the amateur who 
does his own design, construction and repair 
work has improved remarkably over the past 
twenty years! It is hard to imagine how we 
tuned antenna systems without VSWR 
meters and forward/reverse power meters. 
Most of us were lucky if we had a simple 
volt-ohm- miHiameter. Those of us who knew 
what an oscilloscope was considered it far- 
out for application to our amateur problems. 
Today we have a wide range of instmments 
available, varying in sophistication from the 
spectrum analyzer ("Panadaptprs" and 
similar instruments) to gadgets like the 
calibrator to be described in this article. 




Ftmctional Description 

Perhaps the most frustrating aspect of 
using an inexpensive oscilloscope is its lack 
of voltage calibration. This fmstration can 
be easily eliminated by the addition of an 
external calibrator which allows the signal 
under test and the calibrating signal to be 
switched without disconnecting and recon- 
necting the oscilloscope leads. The calibrator 
produces square waves of known voltage 
amplitudes* With one of these square waves 
apphed to the oscilloscope^s input terminals, 
the gain of the oscilloscope is adjusted until 
the signal height on the tube face is a 



convenient number of divisions when 
measured by the reticle in front of the tube 
face. Typically, a ten-volt square wave may 
by applied and the gain adjusted such that 
the square wave is ten divisions high on the 
reticle. Each division on the reticle is then 
equivalent to 1 volt. Similarly, if a one volt 
square wave were appUed and the gain set 
for ten divisions^ each division would re- 
present 0. 1 volts. 



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Circuit Description 

The calibrator circuit (see circuit dia- 
gram) consists of an isolation transformer, a 
rectifier, a Zener diode clipping circuit, a 
step attenuator, and a selector switch. The 
isolation transformer minimizes the electric 
shock hazard. Note that an electrostatic 
shield between the primary and secondary is 
suggested to minimize the coupling of 60 
hertz hum into the oscilloscope's input 
circuit. The rectifier reduces the sinusoidal 
voltage across the transformer's secondary to 
a "half sine wave," L e., to a half- wave- 
rectified waveform. The clipping circuit 
further reduces the waveform to a form very 
close to a squarewave with peak-to-peak 
amplitude of 10 volts. The step attenuator 
provides outputs of 1.0 and 0.1 volts; these, 
and the basic 10 volt square wave, may be 
selected by the switch. 



32 



73 MAGAZINE 




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Physical Description 

The calibrator is built in a 
2-1/4 X 2-1/4x4 inch minibox. The layout 
of parts is simple and not critical and, 
therefore, no drawings have been included in 
this article. Care shoidd be taken to shield 
and separate the test signal leads from the 60 
hertz calibration signal circuits. 

A pair of banana plugs are mounted on 
3/4 inch centers at one end of the minibox. 
These plug directly into the oscilloscope's 
input terminals. A pair of terminals similar 




to the oscilloscope's input terminals are 
mounted on the other end of the minibox 
and are used to connect the test signal. 

The switch has four positions: test signal, 
ten volts, one volt and 0. 1 volts. This choice 
of calibration voltages will allow full-scale 
calibration of the oscilloscope in the range 
from 0.1 volts to 100 volts. 

Conclusion 

The convenience afforded by this cali- 
brator makes it weU worth its cost and the 
time necessary to build it. Its accuracy is 
governed by the accuracy of the Zener 
diode. The diode specified in the parts list 
win give 5% accuracy which is similar to the 
accuracy provided by common panel meters* 
Additional accuracy is probably limited by 
the oscilloscope's deflection linearity and 
the width of the oscilloscope's trace. 

This device will greatly simplify work on 
both transistor and tube circuits. It makes an 
oscilloscope double as a vacuum tube volt- 
meter at minimum cost with the con- 
venience of not having to connect a separate 
instrument to make voltage measurements. 

_ , . WIOLP 



OCTOBER 1969 



33 




That Have Known Me 



Robert Manning Kl YSD 
Vfest Rye, NH 03891 




"Hey, you, you jerk! Yeah you, the 
ham-operator dum dum!'' A voice boomed 
out into the morning stillness and assaulted 
my eardrums as I was leaving for the 
unemployment office (I'm having trouble 
getting work in my chosen profession. 
There's not much call for a human cannon- 
ball anymore— especially since the last time 
out I overshot the net, carromed off the 
cotton candy machine, which ran amuck 
turning most of the audience into a cluster 
of Bo Jangles looking for a Shirley Temple, 
landed smack on top of the tatooed lady, 
turning her black and blue and obhterating 
most of her artwork, startled the fire-eater 
who hiccoughed and set fire to the bearded 
lady which scared hell out of the sword 
swallower, causing him to inadvertantly re- 
lease the spring catch on a Malayan machette 
thus performing not only an auto-appen- 
dectomy, but much more serious damage. 
To this day, whenever he sees me, he kicks 
off his high heels, lifts his skirt and tears 
after me shouting all sorts of threats in a 
shrill voice! I don't know what his complaint 
is— they named a sandwich after him— sliced 
chicken). 



The roar had emanated from one of my 
female neighbors— you know the type— so 
misshapen and ugly that if she'd been seen 
by Moses, there'd have been eleven com- 
mandments. She is the possessor of a cavern- 
ous mouth'so large that, by comparison, a 7 
ply 6:00x16 Goodyear white waU looks like 
a licorice-and -peppermint lifesaver. *'Do you 
know/' she thundered, "that every time you 
play with that radio junk of yours, my toast 
turns black and I start hearing things?*' 

Remembering item No. 32 from the 
pamphlet, "How To Handle TVI Complaints 
With Tact and Diplomacy," I deported 
myself Hke any other mature, gentlemanly, 
self-respecting ham would have done under 
similar circumstances. I jingled the change in 
my pockety brushed back my Alan Ladd 
forelock, straightened my tie, wound my 
wrist watch, picked my nose, checked my 
zipper and, with a yeU of "Blow it out your 
smokestack you beady-eyed daughter of an 
illegitimate pickpocket!'', T hurled the 
largest rock I could find at the big-mouthed 
old bat! 

Unfortunately, I missed the old bag— my 
knuckleball just isn't what it used to be—and 



34 



73 MAGAZINE 




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hit her pet, "Heinrick/* New England*s 
largest living carnivore— a German shep- 
herd— an animal with the mentality of a. 
citizen bander, the disposition of a newly 
appointed '*00" and singularly devoid of 
any form of mirth whoM obviously read 
Mein Kampf and bore a grudge for losing 

WWIL 

Taking refuge in my car, I watched the 
beast eat my fender, headliglit, rear-view 
mirror and top it off with my two-meter 
halo. 

Finally, fully gorged, fully sated and 
having vented his spleen, he started back 
towards his owner. I couldn't resist one 
parting reparte as I drove off in my now 
fender-light-antennaless car, and I said, 
speaking to the dog but in a voice loud 
enough for the neighbor to hear, "See ya, 
Heinrick, and tell your *mother' (with all 
which that implied) that if she keeps hearing 
things, the men in the Good Humor uni- 
forms with the snow-white, crepe-soled 
sneakers are going to certify her as a class 
"A" goober and wheel her off in a wire mesh 
basket wrapped in a wet bed sheet!" 

As 1 rounded the corner on two wheels— 
chortUng and wondering where I was going 
to get a fender for a '36 Hudson Terraplane, 
I heard a loud crash from the rear of the car. 
Later investigation showed that 1 had solved 
one of the old broad's problems. If she 
wanted any more toast— black or other- 
wise—she'd have to run an extension cord all 
the way to my license plate and trailer hitch. 

This is but one of the 800 LT.VJ, cases 
that 1 had been involved in during a five-year 
tour at a trailer park (ofttimes referred to as 
a **horizontal high rise" or **an instant 
slum"). [Now, if the type-setter has kept out 
of the Haig&Haig, isn*t hung over and hasn't 
been distracted by a passing micro-mini 
skirt, as 1 suspect must have happened in 
three of my last four articles, since, in each 
case, a key word was changed, turning an 
otherwise humorous paragraph into a mean- 
ingless jumble of unconnectable words, you 
will notice that I said LT.V.LI 

ITVl is a little complicated to define. The 
initials, of course, stand for Imaginary Tele- 
Vision Interference, but it goes much deeper 
and is more profound than simple imagina- 
tion on the part of an arbitrary or isolated 



television viewer, 

ITVI is the product of the bigotted and 
stagnated mind of ''The VWIOT/' The 
Vidiot (Video Idiot) has become an ever 
growing ethnic group within our society- 
moving into "1984" and "Big Brother" 
twenty years premature. He is totally mes- 
merized by that flickering rectangular eye. 
His entire thought processes, eating habits 
and even his sex life are controlled by 

CYCLOPS! . . . CYCLOPS all hail the one- 
eyed God! . . . "Johnny has to be in bed by 

half past the Flying Nun'* ..•**! want you 
home before The FBI" , . - "The roast wUl 
be done about quarter to ADAM-12 , . . 

(One Vidiot 1 know of became so des- 
pondent when his set was removed for 
repairs that his wife was forced to light up 
the aquarium, sit him down in front of it 
and keep reassuring him that it was a Jacques 
Cousteau Special. When that wore off, she 
mixed him a "Missing TV set cocktail"-'Six 
parts prune juice to one part gin -the Vidiot 
knew the TV was missing, but he was too 
damned busy to really care,) 

The Vidiot comes in two forms. The type 
that has jumped from infancy to senihty 
completely omitting maturity, and the type 
that exists in a limbo state of arrested 
pubescence! 

If you felt the urge for creative analogies, 
you could call them Vidicon Buddhists— 
differing from the "navel contemplating" 
Buddhists only so far as the location of the 
navel to be contemplated is concerned. The 
Vidiot searches for Nirvana through a trans- 
planted electronic and transistorized navel 
installed in a cabinet, but is nonetheless 
connected to it by an ivisible optical/audi- 
tory umbilical cord. 

Imaginary interference can be conjured 
up in the mind of a vidiot at the slightest 
provocation (especially during one of his 
favorite programs— like BOZO or Dark 
Shadows or the Late Night Movie showing, 
"The Oyster that swallowed Mt* McKin- 
ley"), and at the first flicker he can be 
expected to leap into the air with a rousing, 
'^HUZZAH!", whip his bumbershoot out of 
the elephant foot, slam his purple pith 
helmet on his head, yank open the door, 
and, like some modern Don Quixote, 
wearing only the CD pith helmet, jockey 



36 



73 MAGAZINE 



p 



shorts and mucklucks and waving the bum- 
bershoot in one hand and a TV Guide in the 
other, race into the night screaming, "I 
know you're out here— my TV is flickering!" 

Where do vidiots come from and why do 
they hang to this outmoded belief? This 
fallacy -like burying a hank of hair and a 
fingernail at the full of the moon to rid 
yourself of warts, eating raw eggs to improve 
virility, or buying Playboy "just for the 
articles" has been passed on from vidiot to 
vidiot— stupidity is not contagious, but to 
not believe would mean that Cyclops is not 
infallible. 

TV repairmen live in constant terror of a 
call from a vidiot where the set will have to 
be removed. The "sophisticated" repairman 
comes armed with COPE, NERVINE and 
MILLTOWNS; the "average'* repairman 
simply brings along a leather strap or a bullet 
for the vidiot to bite on while the repairman 
pries his fingers off the fine tuning knob; but 
the uncouth repairman simply walks in and 
bludgeons the vidiot with the stubby end of 
an Indian club. 

An IT VI or Vidiot call can almost always 
be distinguished within the first few words 
of the conversation. The vidiot has a ten- 
dency to "gild the lily," the voices he 
hears always **sound" like a ham, the lines 
he SQes always "look" like the Unes of a ham, 
and more often than not he*ll claim that he*s 
hearing Morse code. 

You know this "frograouth" wouldn't 
know Morse code if Marconi, Samuel B. 
Morse and Hiram Percy Maxim were all 
simultaneously hammering out **CQ DX'' on 
the frontal lobe of his cerebrum with an axe 
handle, a No. 9 iron, and a croquet mallet 
respectively. 

It was a common J rather than uncom- 
mon, thing to be interrupted during snoozes, 
showers and other nefarious activities by the 
ringing of Alexander Graham Bell's dubious 
contribution to moderna. (Incidently, I have 
definitely established that the first phone 
conversation was not "Mr, Watson, come 
here I want youf* but rather a call from the 
downstairs neighbor complaining that Mr. 
Bell's infernal machine was interfering with 
the operation of the neighbors' VICTROLA, 
making Enrico Caruso sound like a bari- 
tone!) 



When the phone rings for a TVI call^ as 
some of you are undoubtedly aware, it 
seems to possess a special tonal quality— sort 
of a cross between a death knell and the 
noise your car makes 30 minutes after 
you've mailed off the last payment. 

Picking up the phone on these occasions 
I*d say in my most cordial manner, "Hello 
there! Whom have I the pleasure of addres- 
sing over this veritable miracle of electrical 
science?'* After a slight pause, a voice would 
rumble back^ **Listen you wacky nut— you're 
on my TV and if you don't stop it, I'm 
coming up there and whomp you on the top 
of the head with a 2x4 until you're bowleg- 
ged from the neck down!'' 

*^Ah, forsooth," said I, remembering-be 
nice, be calm, "If you wiU tell me where you 
reside and abide^ Til come down and take a 
look at your TV, for, verily, I haven't had 
my rig on in almost a fortnight!" 

'*Whazzat? Whazzat? What the hell are 

you talking about? Huh? Huh?" 

"I said, where do you hve, stupid?" 

Living as I did in a trailer court where 
your furthest neighbor was as close as 100 
yards and where there were over 80 TV's 
within the area, I thought it a good practice 
to visit anyone with a complaint— just to 
keep good will up and rumors down. In all 
800 cases, I never had a bona fide case of 
TVI attributable to me. This gave me a 
first-hand look at a continuing flow of 
vidiots wliich defies description. At one time 
I thought that I must possess some inner 
personal magnetism that attracted the luna- 
tic fringe like ZSA ZSA attracts and accumu- 
lates jewelry. 

With each call, I would dutifully don my 
**technicaHype" coat— actually a sanitation 
engineer's coat which I'd appropriated at a 
Trailways bus depot— and picked up my 
Interference Portmanteau, which contained 
on one side TVI brochures, high pass filters, 
wave traps and some test equipment (aU 
about as useful in ITVI cases as the "pill" is 
to an octogenarian). On the other side, I 
carried my Vidiot Analytical Conglometer, 

In order to understand the V,A.C., you 
must first understand the mental workings 
of the Vidiot- He will not install a high-pass 
filter or a wave trap, even though they're 
free. He wants someone or something he can 



OCTOBER 1969 



37 



blame, hate and rant about. The V.A.C, is 
my own design and is flexible enough to 
handle most vidiots. 

The Vidiot Analytical Conglometer is 
housed in a 5x6 mini box* There are only 
three basic parts to it: (1) A small variac 
coupled to an ac meter and ac plug- The 
meter is labeled in five stages. Depending 
upon the vidiot you are dealing with, you 
can adjust your conglometer to read the 
cause of his problems as being A, the 
weather; B, the bomb; C; the Russians; D, 
rockets; and E, UFO's* (2) The second part 
is a 3" speaker with alligator clips to parallel 
to the output of the TV— if you can cause a 
feed back squeal^ you can make him believe 
anything, (3) Appearance—the conglometer 
has got to look impressive. I have a rotatable 
tea strainer plumb on top and a two-section 
auto antenna on the side, plus a number of 
lights, knobs and other assorted junk, 

I cannot possibly recount all 800 ITVI 
cases, but I can give you a typical incident. 

Clad in my technician-type coat, I jour- 
neyed to the home of the complainer. My 
eyes had become accustomed to the dark by 
the time I arrived, (Vidiots always call at 
night.) So as I entered the dark, murky 
interior, I could easily make out the semi- 
prostrate form of the vidiot with his hair 
hanging down into his can of Black Label 
which he clutched as if it would take a skin 
graft to remove it. 

I was immediately accosted by two ani- 
mal forms. The first, a futwe vidiot -a sticky 
jam, tar- and glue-fingered, curtain-climbing, 
crumb-grabbing, rug rat that attached itself 
to my leg like Sinbad's "old man of the sea," 
shrieking and screaming something totally 
unintelligible (all vidiots have one or two of 
these around the house; and the second was 
the smallest, nastiest^ noisiest, most pop- 
eyed Chihuahua that Vd ever seen, 

"Clem/* came a voice from the kitchen, 
"tell the man he won't bite!" 

"The dog or kid, lady?'' I asked. "I don't 
mind that bug-eyed canine chomping on my 
shin bone, but if that kid so much as breaks 
the skin, I want a tetanus shot right away!" 

About this time, Clem, the vidiot, de- 
meaned himself to notice me, and brushing 
the ashes and crumbs from his gravy and 
beer stained "T** shirt, he looked up but 



4(' 



CC* 



didn't get up, and in the vernacular of 
vidiots, he said, "Dahh, so you're the ham 
bum that's been screwing up my TV, huh?" 

"You tell him, Qem!" came the voice 
from the kitchen. 

'Took neighbor," I said, trying desper- 
ately to drop the portmanteau on top of the 
dog while trying to get a death grip on the 
40 pounds of animated garbage who was 
now not only trying to get his gooey hand 
into my pocket, but also doing his level best 
to break every bone in my instep. ''1 came 
down to see if I could give you a helping 
hand. I haven't had my rig on in several 
days— now where's the TV set?" 

Don't gimme that crud!" he said. 
'TeU him off, Clem," came from the 
kitchen. 

"I know all about you hams , . . yeah, we 
had one of you guys back in Oklabraska— 
soon as the old man left, the old lady'd get 
on there and start making dates all over 
town. Then the kids would get on there and 
talk to each other," he grumbled officiously, 

"Tell him, Clem!" came the voice from 
the kitchen, 

"And another thing," he said, turning to 
get another beer (I seized this opportunity 
to Norden Bomb sight the goddamn dog and 
surreptitiously twist the kid's ear a full 1 80 
degrees— both went screaming-louder, if 
that's possible-into the kitchen), "That big 
antenna of yours is sucking all the power out 
of my set/' 

"Tell him off, Clem!" came the voice 
from the kitchen (unbeUevably over the 
wailing din of a scrunched dog and a 
twisted-eared kid). 

"You suppose you could show me the TV 
set and keep the commentary for later," I 
said, 

"Smart Bustard, huh? That's it over in 
the corner. Maw had it for 15 years and 
we've had it for 5, Never had any trouble 
except for you hams," he said, indicating a 
large, brown crate about the size of a 
restaurant freezer with what appeared to be 
a broken coat hanger with tinsel hanging off 

it. 

"Where's the screen?" 

"Right there, that six inch hole, see the 
flickering? You're doing that. See what 
you*re doing? Huh? Huh? 



38 



73 MAGAZINE 




*TeII him off, Clem/' came from the 
kitchen • 

"Fm standing right here, so what can I be 
doing? You ever tliink about having *er 
stuffed?" 

'The TV?" 

"No, that voice from the kitchen!'* 
Ducking a beer can, I continued, "Buddy, 
this set is 20 years old and the only way 
youVe gonna get a picture on it is with the 
help of Timothy Leary!" 

"Who's he? Another screwy hara?" 



**Tell him, Clem/' came from the kitchen. 
"Ya know, friend," I said, "I could solve 

all your problems just by inserting a small 

piece of lead in your left ear!" 

"That would fix everything up, huh?" 
"As far as I'm concerned, it would!" 
"How would you insert the lead?" 
"With a .38 Smith and Wesson . , . 

_.K1YSD 

(Type-setter's note: I am not distracted by micro^ 
mini sktts. However, the editor's Bermuda shorts 
occasionally catch my eye ... J 



Mobile Transmitter Heater Switching 

In amateur FM communications opera- 
tion long periods are spent monitoring a 
sometimes vacent channel with relatively 
few transmissions. When I converted an old 
rig to put in my car, it soon became appar- 
ent that keeping the transmitter filaments 
hot would result in a considerable power 
waste from the already overtaxed car bat- 
tery. The receiver uses many filament type 
low current tubes, but the transmitter heat- 
ers waste power- The rig is remotely con- 
trolled in the trunk by a control head and 
connecting cable. No means was provided to 
allow separate switching for the transmitter 
heaters. 

To solve this problem I devised a switch- 
ing method that allowed the desired control, 
but with no extra switches or cables on the 
control head. The scheme is shown in Fig. 
1- When the receiver is turned on, the trans- 
mitter filaments will not be turned on until 
the microphone push-to-talk button is push- 
ed. When the button is pushed, the T—R re- 
lay and Kl will be activated. As Kl pulls in, 
it in turn turns on K2. One set of contacts 
on K2 activates the transmitter heaters, and 
the other set of contacts holds K2 in contin- 
uously. When you wish to turn the transmit- 
ter heaters off, simply momentarily turn the 
receiver power off and the voltage to K2 
wHl be gone. The receiver can then be turn- 
ed on without activating K2, unless the push 
to talk switch is activated. 

In my case^ Kl was not necessary because 
the T-R switch had an extra pair of contacts. 
Be sure that the contacts of K2 can handle 
the current that your transmitter requires. 
Six volt relays can be used with series 
resistors calculated from Ohm's Law, al- 
though this will add to current drain. 

This system can increase power waste 



+12VDC FROM HECEtVER 



EXtSTiNG TR 
Rf LAY COL 



r— — - F" 




TO TRANS 
HEATERS 
— O 



CONTROL 
CABLE 



MICROPHONE 
RTT SWITCH 
IN CONTROL HEAD 



Fig. 1, Power saving heater controL 



during transmission because of the relay cur- 
rent, and some people may not like to wait 
for the transmitter to warm up. However^p 
this was a good solution in my case because 
of my style of operating and limited activity 
on our local channel. If you don't like to 
waste power, and you don't like to run ca- 
bles and install switches where there is no 
room for switches, this system may solve 
your problems too. 

Clifford Klinert, WB6BIH 



MOVING? 

Ev^ry day we get a handful of wrappers 
back from the post offrce with either a change 
of address on them or a note that the sub- 
scriber has n^oved and left no addresSt The 
magazines are thrown out and just the wrap* 
per returned- Pleas© don't expect us to send 
you another copy if you forget to let us know 
about your new address. And remember that 
tfl this day of the extra rapid computer it 
fakes six weeks to make ^n address change 
instead of the few days it used to when we 
worked slowfy and by hand. 



OCTOBER 1969 



39 



Don McCoy WA^HKC 
42S0Hoyi Court 
Wheat Ridge CO 80033 



The Protector 



Here is a practical circuit to have around. 
It can be used for protecting your ham gear 
or perhaps your expensive new color TV, A 
fellow at work was telling me how his house 
power went on and off three times in rapid 
sucession during a storm. He and his family 
were watching their color TV at the time. 
After the power settled down, his TV didn't 
work and it cost something like $130 to get 
it all straightened out* This got me to 
thinking about what such an occurence 
could do to my new solid state color TV. 

The Protector is what I came up with. 
Here's how it works: 

When 1 1 5 volts ac is available at the 
plug, and the fuse is good, the Reset Ready 
light will come on through pins 2 and the 
normally closed pins 5 and 8. Then you 
press the momentary Reset pushbutton. This 
operates the relay by putting 115 volts 
across pins 7 and 2^ which is the relay coil. 
When the relay operates, the Reset Ready 
light goes out due to pins 5 and 8 opening. 
Pin 8 closes to pin 6, which is wired to pin 7 
and the relay "locks up" through its own 
contacts and stays operated even when the 
momentary pushbutton is released. The 115 
volts for the output receptacle is taken from 
pins 6 and 2 which are in parallel with the 
coil The "Thyrector" across the output is to 
limit any surges or transients in the house 
current. 

If the power should go off or dip to 
about 85-90 volts on my particular one, the 
relay will drop out, opening pins 6 and 8. 



Now even if the power comes right back on, 
there is no path to energize the coil or 
supply power to the output receptacle. The 
circuit will stay this way unli! the reset 
button is pushed. 



RESET 
READY 




Frg. 1, Diagram of the protector using a 
G.E. thyractof. Ho. 6RS20SP606. 



1 used a Potter & Brumfield KRPllAG 
because I had one around. Just about any 
single-pole double-throw relay which has the 
contact rating that you need will do. None 
of the parts are critical. The '*Thyrector" 
and Reset Ready light are kind of an 
optional item. Depending on your junkbox 
and scrounging ability, the whole thing 
shouldn^t cost more than a couple of bucks. 

I have mine between the color TV and 
the outlet now^ and it has been working fine. 

., .WApUKC 



40 



73 MAGAZINE 



NOW 




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Buy your new GT-550 
before November 1 st - 

Get the $29.95 VOX 

ACCESSORY FREE! 



YouVe heard about this fabulous Galaxy GT-550,., maybe 
you've even had an opportunity to sit down and try one at your Dealer's 
or a fellow Ham's place. Sooner or later you figure you're going to ov^n 
one — wellj NOW's the time! During the month of October all Galaxy 
Dealers are giving away a VOX Accessory with every GT-550 sold. But 
if youVe going to get one — act now, your order has to be in before 
November 1st, 1969! 



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delay. Controls may be adjusted from outside cabinet. 
Regularly sells for 829,95, 




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OFFER GOOD AT ALL GALAXY DEALERS 



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245 Morning View Drive 
Athens^ GA 30601 



Slower Tuning Rates 

for Older Receivers 



After the oscillator has been stabilized, 
the front end sensitized, and the // crystal- 
Ezed, older receivers still lack a feature 
which makes the newer products attractive 
despite their cost. That feature is a slow, 
smooth tuning rate that allows one to tune 
across and with the signal rather than by it. 
Modern receivers have tuning rates varying 
from ten to 25 khz per revolution of the 
dial. In addition, they are free of backlash 
and have that sraooth-as-velvet feeL Touch is 
part of what sells the browsing ham on the 
display model in the radio shops. 

A couple of years ago, W7ZC/W5CA 
published an idea for slowing down the 
tuning rate of the Drake 2-B. Basically, he 
mounted a Jackson Bros, drive externally on 
the p^nel of the 2-B, using the holes already 
there for panel screws. Thus, he could 
replace the original dial whenever he sold the 
receiver without leaving any tell-tale signs of 
his modification. To add the drive, all he 
needed were a plate to mount it on and 
some L brackets to anchor the plate to the 
panel. The idea is adaptable to almost any of 
the older receivers around and wiU give a 
truly modem tuning rate plus the back- 
lash*free velvet feel that comes from ball 
bearing verniers. 

Since there are still plenty of older 
receivers around just waiting for modificat- 
ion, the original idea could stand some 
updating. It had a couple of drawbacks. With 
the 2-B, for example, moving from 40, 20. 
or 15 to 80 or 10 meters means shifting the 
dial from one end of the scale to the other • 
It takes a while at 7 khz per revolution to do 
this. In fact, one could miss a ten meter 



opening while getting to the left end of the 
scale. Secondly, the W7ZC mounting pre- 
cludes use of the tuning dial scale. Although 
calibration of the theorectically 40 khz scale 
was not accurate because the oscillator was 
not linear, the scale was useful for logging 
purposes when one needed to find a station 

again* 

By revising the mounting scheme and 

chosing an appropriate dial to replace the 
original, it is possible to overcome both 
flaws. In fact, one could even add a logging 
scale to receivers not already having one. 
With a little practice, interpolation of frequ- 
ency to tenths of a khz is possible and 
practicaL 

The first job is to find a dial that will 
pernoit the use of both the 6-to-l reduction 
and the straight-through features of the 
Jackson drive. That part is easy. The Galaxy- 
transceivers and the WRL Duobander use a 
dial which internally holds a Jackson vernier 
unit. If you order one or the other from 
WRL as replacement parts, make sure you 
onler all the pieces and ask for the hardware. 
They didn't send the little 2-56 screws to 
fasten the straight-through dial to the ver- 
nier, but perhaps this was an oversight. The 
difference between the Galaxy and the 
Duobander dials is that the former has a 
logging scale already scribed on the outer 
dial. If your receiver does not already have 
such a scale, this dial just might fill the bill. 
You might also want to get the little plastic 
piece that serves as a setting marker. Since I 
have a 2-B, I ordered the Duobander knobs. 

Before showing how to mount the new 
dial, I should warn that anyone used to a 



42 



73 MAGAZINE 





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large tuning knob will find the two-speed 
dial awkward at first. It takes two fingers to 
turn, and the straight-through takes effort, 
since it has to move the little knob at six 
times the speed. It is a case of mechanical 
disadvantage. No more one-finger spinning 
from one end of the band to the other. But 
the whole point of the two speed dial is to 
be able to get to the part of the band which 
interests us and then to have really fine 
tuning. 

A tip on tuning technique: don*t tune 
overhand • It will tire you out in a few 
minutes. If the dial is low enough^ rest the 
back of your wrist and hand on the table 
and tune underhand. The technique gives 
you smooth tuning and a precise feel. Your 
hand and arm muscles work only at tuning 
(which takes little effort) instead of tuning 
plus supporting the arm and hand (which 
takes a lot of effort). Little things make the 
difference between pleasant operating and 
tiring battles. 

With the WRL dial, the whole assembly 
can be mounted closer to the panel than 
W7ZC described. The Jackson drive extends 
only about a 32nd beyond the dial* Using 
the sketches as a guide ^ mount the dial and 
drive on a plate the same diameter as the dial 
on one side, and as long as necessary on the 




CABINET 



-6-32 

SET SCRIlf 
HOLC 



other. The rounded side allows you to 
mount a calibration scale behind the dial, 
which is about the same diameter as the 
original 2-B dial. Since the plate is needed 
only to prevent rotational movement (the 
shaft does the main supporting job), it need 
not be heavy or large. Eighteen guage alumi- 
num or slightly thicker bakelite is fine. For 
the 2-B, I cut a second piece that crosses the 
extension as a T in order to fit the panel 
holes available. Cutting the original as a T 
would work just as well. 

The two-piece version has an advantage: 
it allows final alignment so that everything 
turns smoothly. It is a good idea to drill aU 
screw holes in a slot shape and to let the 
screws and lockwashers do the job of hold- 
ing things in place. No matter how carefully 
I measure, I am always a bit off with the 
drilL After getting fed up with the modifi- 
cation because the drive would bind^ I 
realized that it wasn't lined up properly. The 
slots let me tighten the drive to the shaft 
first and then align the plates to it. Now the 
drive works as smootlily as without any 
load. 

By using 4-40 screws (which fit through 
the sheet metal screw holes without reaming 
them out) and a bunch of extra nuts I had 
lying around, I solved the spacer problem. 1 



FIBCR WASHER 



^g SPACER 



CHASSIS 



Z 5FEED OiAl.-^ 



6-32 NUT, BOLT, 
AND LOCKWASHER 




I KHZ SCALE 

PANEL 



FRQMT V;EW 



SlOe VtEW 



•jj_ 0.- !^tD. WASHERS OR 
OTHER SUITABLE FRICTON 




CHASSIS 



^g SPACER 



FIBER WASHER 
(ALREADY THERE) 



Fig. 1\ Mounting of plates and two-speed 
d?aE/drive as applied to the Drake 2-B re- 
ceiver. Modify as required by the particular 
receivdf being adapted for a slower tuning 
rate. 



BOTTOtI VIEW 



44 



73 MAGAZINE 




recommend 3/8 inch spacers, but 1/4 inch 
spacers with solid washers on top and fiber 
or felt washers against the panel to prevent 
marring will do as well. For other receivers, 
the size of the spacer will depend on how far 
out from the panel the dial shaft extends. 

The shaft of the drive requires a half to 
5/8 inch hole. I used the larger size because I 
wanted to keep the 2-B calibration plate. It 
is kept turning by a spring on the dial shaft 
pushing against the plate which in turn 
pushes against the dial. Since the Jackson 
drive does not push onto the shaft as far as 
the original dial, there is space to be filled 
up. Tubing with an inside diameter of 1/4 
inch of either metal or plastic, or even a gob 
of electrical tape wound around the shaft 
will do nicely. The aim is to keep the plate 
turning with dial rotation but to allow 
freedom enough to reset it at will. I had a 
large number of 1/4 inch inner and 9/16 inch 
outer diameter washers which sUd very 
nicely onto the shaft. Just choose the right 
number for the shaft length to be filled up. 
The advantage of the washers is that if 
something binds, the washers will turn 
against each other so that nothing is dam- 
aged. But under normal tuning^ they turn as 
a unit because of their friction contact with 
the shaft and with each other. 

The same idea can be applied in adding a 
scale to a receiver without one. The 2-B 
backs up the spring by a wide margin on the 
shaft, A washer against the panel, a spring, 
another wide washer, and then a felt washer 
with a drop of oil on it against the back of 
the scale plate will allow the plate to turn 
freely if something heavier on the friction 
goes between the plate and the drive. The 
gob of tape or a metal spacer with dry felt 
washers on either end will do the trick here. 

For a professional look, paint the metal 
plate holding the dial black or to match or 
contrast with the receiver panel and knob. 
To impress your friends with your home 
brew ability and with the fact that you are 
one up on them with the same old gear, 
leave it a shiny aluminum or raw bakeUte. 
The entire job is quite simple (about two 
hours work), but it gives the impression of 
immense complexity and ingenuity. And 
when you tune in your caUbrator note and 
can hear it for a couple of revolutions of the 



\ HQL€ 

TO FIT E>5S SCREW 




"€3- 



LEMQTTH AS FtCaO 






'^ 



M 




If? 



■ o 



^>- 



-e 




_sr 



Ftg. 2. Plates needed for mountirrg two- 
speed dial/drive. Adjust dimensions to fit 
particular receiver being modified. 
Note: dimensions of slots not crttical, but 
koep slots aligned as shown. Reversal of 
directions allows plate holding the dial to 
slip more easily as the dial is rotated. Lock- 
washers are essential in fastening the two 
plates together, 

dial, you will amaze everyone, includmg 
yourself. 

The real advance is in operating ease. 
With a slow tuning rate, you will hear 
stations that you previously passed over as 
part of the popping Une noise and QRN. 
Now they have a tone that rises or falls 
depending on which sideband you are tun- 
ing. "You can't work 'em if you can't hear 
*em", is an old saying, and we can add that 
being able to recognize a signal is half the 
job of hearing the hard ones. 

An ultra-slow tuning rate is useless with- 
out a stable receiver. Some receivers drift 
faster than one could turn the knob of the 
new drive to follow them. That is another 
place the straight-through knob comes in 
handy. But stability comes first on the 
receiver modification priorities. Once you 
have achieved that or have a receiver like the 
2-Bj which remains stable even as it grows 
old, then you can concentrate on tuning rate 
and cahb ration. Here, the WRL knob and 
the Jackson Bros, drive really help. And this 
is the point where I came in, 

.„.W4RNL 

*David Middleton, W7ZC/W5CA, "Slowing Down 
the Tuning Rate on the Drake 2-B/* 73, Septem- 
ber, 1965 J p. 44- 



OCTOBER 1969 



45 



A, R McGee, Jr, K5LLI 
28 IS Materhorn Drive 
Dallas, TX 75228 




Positive Identification 



Calibrator Harmonics 



The availability of low-cost high- 
frequency transistors and integrated circuits 
has made it possible to build inexpensively a 
100 khz crystal calibrator with useable 
harmonics extending into the region of 400 
to 500 rahz,* This means that you will have 
perhaps 4,000 or so crystal controlled signals 
available, all of which sound exactly alike 
when tuned in on a receiver. It is a real 
problem, therefore, to determine which 
harmonic of 1 00 khz is being received at any 
given time* 

The usual method of identification 

On the lower frequencies, when using a 
general coverage receiver, you can tune to 
WWV at some known frequency, and by 
carefully tuning away you can count the 
number of 100 khz harmonics tuned 
through until you reach the desired fre- 
quency. For example, if you wish to locate 
7.0 mhz, you can first tune to WWV at 5.0 
mhz, then tune higher in frequency until 
you come to the twentieth 100 khz 
harmonic above 5,0 mhz^ This wiU be 
exactly 7.0 mhz. Of course, you must be 
sure of which WWV signal you are tuned to, 
but since the WWV transmissions are spaced 
at such wide intervals (2,5 mhz between the 
2.5 and 5.0 mhz signals, and 5 mhz between 
the 5.0 through 25.0 mhz signals) there is 
little likelihood of making a mistake, even 
with a poorly calibrated receiver. 

Fossibility of error 

With a limited-coverage receiver, such as 
the ham-bands-only type, you can tune to 
7-0 mhz and perhaps you will hear a 100 khz 
harmonic at this dial setting. This is 
probably the 70th harmonic of 100 khz at 



7.0 mhz, but it could also be the 69th at 6.9 
pihz or the 71st at 7-1 mhz, and the 
indication would stiU be exactly the same- 

At higher frequencies even a receiver with 
a wide tuning range will have the same 
difficulty. For example, say you build a 
receiver covering the range of 100 mhz to 
120 mhz. A grid-dip meter will get you 
somewhere near the desired range, but the 
100 khz calibrator will be useless for 
accurate calibration because you will be 
unable to positively identify any of the 200 
or so 100 khz harmonics that you will be 
able to hear. 

What is needed is some means of giving 
each harmonic some characteristic that 
would distinguish it from all of the other 
harmonics generated by the 1 00 khz calibra* 
tor. 

A new method of identification 

A simple way to do this would be to use 
two crystal calibrators. One calibrator would 
operate at exactly 100 khz, while the other 
would be adjusted to operate slightly above 

100 KHZ 



1ST XTAL 
OSC 


- 


HARMOMIC 

GEN 


— 


F 

P 






















fiCVfi 


Fo 


FREQUENCY 
QQ\JHJi,R 




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/• 












/ 






2 m XTAL 
OSC 


- 


HARMONIC 
GEN 





AUDIO 
OUTPUT 

1 
1 











Fig. 1. Block diagram of proposed method 
of identifymg lOOkhz calibrator harmonics, 
f=freqy@ncy of lOOkhz harmonic tuned to. 
f1=frequency difference in hertz between 
first and second oscillators, fo-audio output 
frequency in hertz. 



46 



73 MAGAZINE 



INTRODUCING THE 



DELUXE 






MODEL 270 ... 5 BANDS ... 260 WATTS 



The deluxe Cygnet is a complete amateur radio 
station including AC and DC power supply and 
loudspeaker, beautifully integrated into one pack- 
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station operation with enough power to work the 
world. Yet the 270 is compact and light enough 
to make an ideartravelmg companion on those 
business or vacation trips (second only to the 
XYL, of course). Incidentally, a carrying case for 
the Cygnet will soon be available. 

For temporary mobile installation, either in your 
own or someone else's car, Swan will soon ofler 
an installation kit, including antenna, which will 
put you on the air in 5 minutes (no holes). Thus, 
you'll be able to operate mobile from a rental car! 
For permanent mobile installation, your Swan 
dealer has mounting kits and 5 band antennas 
in stock. 

For those who feel they need higher power to 
climb above the QRM tevel. Swan will soon an- 
nounce a matching 1 KW Cygnet Linear. It will 
also come with a handle just in case you decide 
to take its 25 pounds along on a trip. With this 
much power of course, it works only on AC. 




SPECIFICATIONS: Power Input: 260 watts P.E.P. tn SSB 
voice mode, and ISO watts in CW mode •Frequency Range: 
3,5-4.0 mc. 7.0-7.3 mc. 14.0-14.35 mc. 21,0-21.45 mc. 28.0- 
29 7 mc • C,F, Networks: Crystal Lattice Filter. Same as 
used in the Swan 500 C 2 J kc band width at 6 db down. 
4.6 kc wtde at 60 db down. Ultimate rejection exceeds 
lOOdb 9 Unwanted sideband suppressed. 50 db. Carrier sup* 
pressed 60 db. 3fd order distortion down approx, 30 db # 
Audio Response: flat wjthin 3 db from 300 to 3000 cycles m 
both transmit and receive modes • Pi Antenna coupler for 
52 or 75 Ohm coaxiaJ cable • Grid Block CW keying with 
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than \z microvolt at 50 ohms for stgnal-plus-noise to noise 
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or below 100 khz. Let's see what would 
happen if the second oscillator frequency 
were made 100 khz plus 10 hz, or 100.01 
khz. The 100 khz and the 100.01 khz signals 
are fed simultaneously into a receiver that is 
equipped with an AM detector. If the 
receiver is tuned to 100 khz, there wiU be 
audio output signal, the frequency of which 
is equal to the difference in the two 
oscillator frequencies* In this case the 
difference is 1 hz. 

Now we will tune the receiver to the 
second calibrator harmonic at 200 khz. The 
second harmonic of the 100 khz oscillator 
will be 200 khz, and the second harmonic of 
the 100.01 khz oscillator will be 200.02 khz- 
The difference frequency is now ,02 khz, or 
20 hz, which is the audio output frequency. 
The third harmonics of the calibrators would 
be 300 khz and 300.03 khz, which would 
give an audio output of 30 hz, etc. 

As we go up in frequency the spacing 
between the calibrator harmonics becomes 
greater and greater, increasing exactly 10 hz 
with each consecutive harmonic. This could 
theoretically continue until you reached an 
output frequency of 50 khz, but the rf and 
audio bandwidths of most receivers would 
prevent going this high. 

In order to determine which harmonic we 
are tuned to, we only need to measure the 
frequency of the audio output tone in hertz 
and divide by 10. Multiplying this answer by 
1 00 khz wiU then give the correct frequency. 
After determining the frequency, you can 
turn off the oscillator with the 10 hz 
frequency offset and zero the receiver on the 
exact 100 khz harmonic for an accurate 
calibration point. 

Now if you tune a limited-coverage 
receiver to 7.0 mhz, and with both cahbrator 
oscillators running you have an audio output 
of 700 hz, you can be certain that you are 
actually tuned to 7.0 mhz. This is the only 
frequency, for all practical purposes, where 
you would have a 700 hz output frequency, 
6.9 mhz would give an output of 690 hz, 
while 7-1 mhz would give an output of 710 
hz, etc. 

Technical details 

The audio output frequency would have 
to be measured very accurately - at least to 
the nearest 10 hz or whatever 100 khz 
frequency offset you may be using, A 
frequency counter would probably be 
required to get accuracy of this order. This is 
no longer the hang up it would have been a 
few years ago. The introduction of in- 



expensive integrated circuits has made it 
possible to build a good frequency counter 
at relatively small cost.^ ? Some of the older 
tube- type counters are also available at 
surplus outlets at reasonable prices. 

For our purposes the counter would only 
need to be capable of measuring the audio 
frequencies. The bandwidth of the receiver 
would be the limiting factor in most cases, 
and the 100 khz frequency offset would 
have to be set so as to get a useable output 
from the receiver when tuned to the desired 
100 khz harmonic. For example, if the 
receiver bandwidth is 10 khz^ with a 10 hz 
offset the highest measurable 100 khz 
harmonic would be the 1000th, or 100 mhz- 
With a 5 hz offset you could measure to 200 
mhz, with a 20 hz offset you could measure 
to 50 mhz, etc. 

The two calibrator oscillators must be 
accurately adjusted to their proper fre- 
quencies. In order to set one oscillator to 
exactly 100 khz, first tune the receiver to 
WWV at the highest receivable frequency 
where a steady signal can be heard. Wait 
until the tone goes off (the last two minutes 
of each five- minute period) and adjust the 
calibrator frequency for zero beat. Watch 
the receiver S-meter. When you are close to 
zero beat, the meter wiU begin to move back 
and forth at a rate equal to thp frequency 
difference. Adjust the oscillator trimmer 
carefully until the meter moves very slowly 
and then stops. This wiU be exactly the 1 00 
khz point. 

The other calibrator can be offset the 
correct amount from 100 khz by using the 
counter to measure the beat note between it 
and WWV, For example, with a 10 hz offset 
you would adjust the oscillator for a 1500 
hz beat note with WWV at 15 mhz (the 
150th harmonic of 100 khz), or a 2,000 hz 
beat with WWV at 20 mhz, etc. 

The 100 khz calibrator oscillators must 
be very stable. A transistor oscillator built 
with high quality parts and powered by a 
mercury battery would probably meet the 
requirements. A simple 100 khz transistor 
oscillator developed by the National Bureau 
of Standards has a short-time frequency 
variation of about three parts in 10,000 
million, and a long-interval variation of 
about three parts in 1 000 million.* 

You would have to take care that the 
oscillators would be subjected to as little 
change in temperature as possible. Of course, 
if similar parts are used in both oscillators, it 
is probable that they will drift at approxi- 
mately the same rate with temperature or 



48 



73 MAGAZINE 




+ cables 
^ connectors 

* accessories 

* applications |^ 




(g(o)©S 







wsimmix 





3.00 



voltage changes. Thus the relative fre- 
quencies of the oscillators would not change, 
and the location of the received harmonics 
would still be correctly indicated. 

Receiver stability would not be a deter- 
mining factor in the accuracy of this system, 
as long as the caUbrator harmonics could be 
held withm the pass band long enough to 
enable measurement of their frequency 
difference. 

Since this output frequency is the result 
of the calibrator harmonics beating against 
each other in the AM detector, a slight drift 
in the receiver local oscillator will not cause 
a change in the output frequency, but only a 
decrease in its amplitude- 

Considerable thought has been given to 
the ideas expressed here, and I believe that 
their proper application would result in a 
simple, practical method of positive identi- 
fication of any individual 100 khz harmonic 
heard on a receiver. I have not tested this 
system, however, mainly because I do not 
yet have a frequency count er< 1 don't think 
any great problems would be encountered, 
except possibly in the stability of the caU- 
brator oscillators. 



CHARTS AND DATA 

ON EVERY TYPE OF COAX 

KNOWN TO MAN. 

INVALUABLE (VALUABLE) BOOK 

FOR THE HAM - THE LAB 

- INDUSTRY 



I 
I 



SEND ORDER TO: 



I PETERBOROUGH 
I 

I Name 

I 



73 MAGAZINE 
N.H. - 03458J 



Address ^ 



I 

I City. 

. Slate 



Zip, 



$3.00 enclosed for one 

Coax Handbook, postpaid. 



I 

I 

i 

I 

References: (1) Ashe, "lUU ktiz 1 liin-Line Pulse 
Generator," 73, February, 1968, p, 24. (2) JoneSj 
''An Integrated Circuit Electronic Counter j" 73, 
February, 1968, p. 6, (3) Suding, '*A Cheap and 
Easy Frequency Countefj" 73, November, 1967, p, 
6» (4) Kiver, Transistors in Radio and Television ^ 
McGraw-HiU, 1956, p- 141. 



Ham Tips: Save That Shielded Braid 

Normally discarded shielded braid can 
be used as both a soldering aid and a heat 
sink. To utilize the braid as a soldering aid, 
dip the tip of the braid into some rosin flux. 
When desoldering components, heat them 
first and then touch the braid to the 
terminal The mesh on the braid will act as a 
sponge and soak up the solder, leaving the 
terminal clean and solder-free. 

When soldering to heat-sensitive compo- 
nents, use the braid minus the flux to 
conduct excess heat away from the compo- 
nent 

As the solder fills the braid, simply clip 
off the solder filled portion leaving fresh 
braid for future use. 

Happy soldering! 

ElUott S. Kanter, W9KXJ 



OCTOBER 1969 



49 



Adapting 




W, B. Cameron, WA4UZM 
324 South RiverhUls Drive 
Temple Terrace, Florida 3361 7 



Transmitters to FM 



In many parts of the country, one of the 
most popular bands today is two-meter FM, 
Most of the equipment is obsolete com- 
mercial equipment which has become avail- 
able to the amateur market because changes 
in the standards necessitated replacement of 
the old wide-band gear with newer narrow 
band equipment. Some new FM transceivers 
designed especially for the amateur market 
are beginning to appear, but they are in the 
$300 range. If the amateur does not have 
access to obsolete commercial equipment or 
the inclination to adapt it to amateur 
frequencies, he may feel cut off from this 
interesting mode of operation. However, it is 
possible to get on the air experimentally by 
adapting existing AM equipment, as this 
article will show. 

The first thing to do is to receive some- 
body else's signal. If you have a two-meter 
converter, you can do a passable job of 
receiving strong local FM signals by slope- 
tuning an AM receiver, or using an FM 
adapter which is available for some receivers. 
If you are receiving narrow-band FMj the 
product detector in a sideband receiver 
works very well. 

Once you have heard something on the 
aiij the next problem is how to talk back to 
it. If you have an existing two-meter AM 
transmitter, the likelihood is that it uses 8 
mhz crystals- The easiest way to adapt this is 
to build a separate FM generator which 
produces a signal on 8 mhz and inject it at 
the crystal oscillator stage, 

I converted one such transmitter by 
removing the AM modulator stages, and 
utilizing the sockets which were there to 
make a three tube FM generator. The diagram 
and parts values are shown in Fig. 1-Two 
6SL7 tubes and one 6SG7 are used. These 
were selected simply because the octal 
sockets were already in the chassis. More 
modem equivalents can be substituted and 
only very slight modifications in parts values 
may be required thereby. 

One 6SL7 serves as a high gain voltage 



amplifier for a high impedence microphone. 
There is nothing very special about this 
except that it has an rf trap in the input, 
which is a good feature to build into any 
high frequency transmitter. You may not 
need it, but rf has a nasty way of getting 
into the grid of the first tube without it. 

The other 6SL7 serves as a Pierce oscilla- 
tor and a PM modulator. You will note that 
there are two variable capacitors in the 
crystal oscillator circuit- The 25 pf capacitor 
is a vernier frequency adjustment for 
bringing the crystal exactly to the right spot. 
The 100 pf capacitor controls feedback- The 
two capacitors interact somewhat, and the 
feedback capacitor can actually be replaced 
in most cases with a small fixed mica of 20 
to 50 pf, but if you put the variable in to 
begin with, you have the advantage of 
adjusting for optimum output even with a 
balky crystal This may prove to be 
important, especially if you have to doctor 
the crystal onto frequency yourself, 

Divide the desired output frequency by 
36, which will place the crystal in the four 
megacycle range (146,940/36 = 408L666), 
You can order a crystal with^ reasonable 
tolerance from a number of the firms who 
specialize in regrinding surplus crystals. The 
crystal I obtained proved finally to be 
slightly too high in frequency to net with 
other stations on the air. The 25 pf con- 
denser was not sufficient to bring it all the 
way to frequency, so I used one of the old 
ham tricks, I opened the crystal holder and 
carefully drew a 1/8 inch circle with a lead 
pencil right in the middle of one side of the 
plate. Upon reassembly^ this proved to have 
moved the crystal just enough so that the 
APC padder would puU it precisely zero beat 
with other stations on the air, I found a 20 
pf fixed capacitor suitable for the feedback 
circuit, although some crystals and tubes 
might require as much as 100, Obviously, a 
crystal oven would be better than a **raw" 

crystal, if it is available* 

The second half of this 6SL7 tube is a PM 



50 



73 MAGAZINE 




4 MHZ RANGE 

X TAL 
\ .002 



OSC MODULATOR ' 

100 MICA 100 MICA , 50 MICA 



6SS7 g 



100 PF 





TO RF 
OUTPUT 



0047 0047 

1 1( * w^HR 



8 



CRYSTAL EXAMPLE 



40aJ 666 X 36 • 146 940 



to WFD 

300 V 



vw 

47 IC 



-► B + 



Ffg, 1. Simplified 8 mhz FM generator and crystal substitute. 



modulator. Do not bypass the 22K resistor 
in the cathode as this degeneration is im- 
portant to the operation of this stage, I will 
not detail how this particular modulator 
works except to note that it produces almost 
as much amplitude modulation as phase 
modulation. The amplitude modulation 
disappears after the signal is passed through 
a number of saturated stages, which is one 
way of describing the hard driven multiplier 
stages in the typical transmitter which has to 
multiply a fundamental signal 36 times to 
get on the frequency. You can check with 
the sensitive rf meter at various stages along 
the line to observe decrement in the existing 
amplitude modulation. By the time you get 
to the final, there should be none at all. 

This does require that the first amplifier 
after the modulator be a very sensitive high 
gain stage. I found a 6SG7 to be a very 
suitable tube for this purpose. Any number 
of miniature tubes w0 serve as well. The 
only thing you might need to change is the 
screen grid dropping resistor, which should 
be adjusted to provide the proper screen grid 
voltage as indicated in tube charts. One 
further question remains and must be left 
open to experimentation and to the taste of 
the operator. This is the question of audio 
frequency response. PM tends to sound 
tinny and some roll off of high frequencies 
in the transmitter or receiver is required to 
give a more pleasing sound. This can be most 
easily accomplished by shunting the grids 



and /or plates of the 6SL7 speech stages to 
ground with various size capacitors until you 
get the sound you want. 

Obviously, this simple equipment is not 
likely to give you the best signal on the 
band, but then you haven't invested much in 
it either. If this mode of operation intrigues 
you and you want to carry experimentation 
further, the next thing I would recommend 
is a clipping or compressing circuit in the 
speech stages. This wiQ help maintain a 
higher average deviation while restricting the 
peak deviation. This serves the same basic 
purpose as ALC in a side band transmitter or 
clipping and compressing in an AM 
transmitter, namely that it keeps the 
apparent percentage of modulation at the 
receiver high despite a wide variation in the 
actual level of sound input at the micro- 
phone. Again, just as with speech treatment 
in these other modes, excessive compression 
or clipping will distort the sound patterns 
enough to give the transmitter a very 
artificial sound. Taste and judgement are 
required, and for this, you need a good 
friend on the air who can give you a 
technically competent and honest report. 
This may be the hardest part of the whole 
operation to come by, but the FM fraternity 
is still new enough to include a great many 
experimenters, and you can probably find a 
sympathetic critic in your area if you look 
for one. 

- , , WA4UZM 



OCTOBER 1969 



51 



Rob McKnIght V/B2FHW 
Dave Schmarder WA2HNJ 
318 Dewey Avenue 
Buffalo. NY 



CB Sets on 




The band primarily used for local con- 
tacts is six meters. It is uncrowded and 
transmitters with very low power as weU as 
receivers with modest selectivity are widely 
used. Lack of a simple station for six, 
however, keeps many otherwise enthusiastic 
operators away from this band. Having to 
build a converter for the station's present 
receiver, and an entirely separate transmitter 
for six is not very appealing to many 
operators. This article has the answer to 
their problem. Its subject is the conversion 
of the ordinary, everyday CB set to six- 
meter operation. Several advantages make it 
worthwhile: L the set already has the basic 
transmitter and receiver circuits and thus is 
easy to convert; 2. its transceiver type of 
operation is convenient to local contacts; 
and 3, it would make an ideal local vhf net 
monitor If you were a CB*er turned ham 
and still had the old rig hanging around^ you 
would have the added bonus of not having 
to find a CB set to convert in the first place. 

The major requirement is that you obtain 
a CB set suitable for conversion. By suitable 
I mean that it should be a tube type rig and 
not a transistor one. Transistors in the receiver 

work at 27 mhz, but they may not work at 
50 mhz- You would save yourself a lot of 
trouble by working with tubes. As far as test 
equipment goes, a vtvm and a grid dip meter 
are very helpful- 
Conversion 

The receiver section of the transceiver is 
converted in the foUowing manner: 

L Tune into the CB band, tune up the// 
cans, and get the set working satis fact orily* 

2, Resonate the rf and mixer coils to 50 
rahz with the grid dip meter- Since the 
oscillator usually runs above the if fre- 



quency, adjust the oscillator to its proper 
frequency. The receiver is now ready to 
operate. 

3, Tune up a signal on six meters. In place 
of the present tuning capacitor, if it tunes 
too great a range, substitute one with a 
smaller capacitance or remove several plates 
from the one in the set to give less frequency 
range. This, however, may not be desired, as 
one may wish to receive, for example, a 
MARS frequency^ in which case he would 
rather leave the original tuning capacitor 
untouched. This finishes the receiver 
conversion. 

The transmitter section of the transceiver 
is converted as follows: 

There are two ways to convert the trans- 
mitter: 

1. Leave the original oscillator in the 

circuit and resonate its output coil to 50 
mhz. Insert a 5 mhz overtone crystal in the 
oscillator and you*re finished. Overtone 
crystals, however , are more expensive than 8 
mhz ones, and are usually not used in 
today*s six meter rigs. On the other hand, 
use of an overtone crystal requires one less 
stage in the completed rig. 

2. The second method of conversion and 

probably the most widely used is the use of 
an 8 mhz oscillator-tripler stage and a 
doubler stage. Refer to the circuit diagram 
for details. Important: Be careful not to 
leave out any bypass capacitors or any B+ 
decoupling resistors, otherwise the unit may 
fail to oscillate, or a stage may not work 
properly. An extra tube is required in this 
circuit, that being the doubler stage, which, 
as indicated, can be a section of a 12AX7 or 
a section of a 6U8- In addition L4 should be 
wound inside of L3 for good coupUng. The 



52 



73 MAGAZINE 




O5CILLAT0*? TRIPLE!? 
eSHS Oft 6A06 



aSMNz 



DOuetER 

l/Z IZAX7 0R (/2 6Ue 

50MH1 
^t ♦■ 



r2BY7 



50MH2 



.005 



Q-< 



SMHz 




Fig, 1. Circuit diagram of the converter transmitter using the 8 mhz oscilfatortripler and the 
doubler stage. Coils LI, L3, L4 were afready in the set. L2 was obtained from an old TV 
chassis. This circuit diagram may seem a bit incomplete, but since every CB set is different, 
the circuit must be broad enough to cover all models. As a result, some experimentation will 
be necessary to determine the proper coils to be used. 



transmitter conversion is now complete. 
Tune Up 

Procedure: L Hook a No. 47 pilot lamp 
on the antenna jack or terminals, 

2. Set each coil for the approximate 
frequency indicated on the circuit diagra nu 

3. Make sure the oscillator is functioning 
properly. This can be determined by lis- 
tening to the signal in a nearby receiver. If 
there is a spot switch on the set it can be 
used to listen to the oscillator in the 
transceiver's receiver, 

4. Put the rf probe of the vtvm on the 
grid of the doubler stage, and tune LI for 
maximum rf indication on the meter (maxi- 
mum pointer deflection). If an rf probe is 
not available, put one end of a 1N34 or an 
equivalent diode on the end of the vtvm's dc 
probe, and touch the free end of the diode 
to the circuit to be measured, 

5. Place the rf probe on the grid of the 
final, and tune L2 for maximum rf indica- 
tion, 

6. Place the loading capacitor at mini- 
mum capacitance, and tune the plate tuning 
capacitor for maximum brilliance of the No, 
47 pilot lamp previously hooked up. In- 
crease the loading by increasing the capac- 
itance of the loading capacitor, and then dip 
the current using the plate tuning capacitor. 

7- If an overtone crystal is used instead of 
the 8 mhz oscillator-tripler, the transmitter 
should be tuned by resonating the oscillator 
plate coil to 50 mhz. The rest of the tuning 
is done as described above. 

You now have a complete low power 



station for six meters- All that remains to be 
done is to hook up the antenna and a mike. I 
might add that there is really no need to 
have to switch the beam from the big six 

meter rig, that is if you have one; the set got 
out quite well on a simple dipole mounted 
on a stick of board. The total cost of 
converting the rig was nothing^ as all the 
necessary extra parts were available from the 
shack junkbox. So if you want to have some 
fun on the band which is becoming more 
popular every day, try this simple con- 
version; you'll be glad you did! 

. _ WB2FHW & WA2HNJ 

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OCTOBER 1969 



53 



Proportional 



Cont rol 



Crystal 



Robert S. Larkin, W2CLL 

RFD I Box 28R 

Flanders, New Jersey 07836 



Oven 



When the ultimate in stability is required 
in an oscillator, a temperature controlled oven 
must be used. Until recently, ovens took the 
form of a box surrounded by a heating ele- 
ment and containing a thermostat. When the 
temperature is too low the thermostat closes, 
causing the heating element to come on. Af- 
ter the temperature rises to the thermostat 
switching temperature the heater goes off, al- 
lowing the box to cool down. This process 
continues with a full cycle usually taking a 
few seconds. One limitation of this system is 
having the heater either on or off This 
means that at all times there is either too lit- 
tle or too much heat being applied. The re- 
sult is a cycling of the box temperature as 
the heater goes on and off. 

In the course of some uhf communica- 
tions experiments* where a stable frequency 
and time reference were required, the oven des- 
cribed here was built. This oven is capable of 
much better temperature control than the old 
thermostatic type of oven. Proportional con- 
trol is used to allow the correct amount of 
heat to be applied. Once the temperature of 
the oven reaches the correct temperature, the 
heater power adjusts to some level between 



AC FEEDSACtC 





THERMISTOR 



i-OrLTLJ! 

I H£AT£R I 



I OVEf>i I 

Fig. 1. Simplified diagram of oven tempera- 
ture control. 

all off and all on and stays there. If there is 
a change in the temperature outside the oven» 
the heater power will readjust automatically 
to keep the oven temperature constant. This 
type of oven is used in almost all precision 
frequency standards in commercial use today. 
Many ideas used in the design of this oven 
came from an article by WX- Smith ^, 
An interesting aspect to this type of oven 
is its relatively low cost. With any kind of 
junk box at all, this proportional oven can be 
built for less than the cost of a thermostatic 
type crystal oven- 




^^^^^2 



^3 I 



Vector board is used for the electronics. 
The 2 watt heater resistors can be seen 
clamped around the Minibox oven. When 
used, the oven is covered by insulating ma- 
terial. 




54 



73 MAGAZINE 



JULY 20, 1969... Astronauts beam "live" TV pictures direct from moon to earth!! 

Even though YOU can't go to tranquility base... 



OWN 



T 




*f. 



Join the SPACE-AGE" Jet- set 



,.. build a SoJJcf State TV Camera! 











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Circuit 

Operation of the oven control is best un- 
derstood from the simplified diagram* The 
thermistor is a temperature sensitive re- 
sistor^. Mechanically, it is attached to the 
inside of the oven case. Electrically, a bridge 



circuit is formed so when the resistance of 
the thermistor is equal to that of resistor R, 
no voltage is fed back to the input of the ac 
amplifier. When the thermistor is cooled, its 
resistance increases. By choosing the correct 
phasing of the transformer windings, this will 
cause positive feedback around the ac ampli- 



+ 12 V 3 AMP WAX, 




2N404 



CAPACITANCE IN UFO 



Fig, 2. Diagram of proportional oven control as described in text. 

R1 Thermistor, 10000 at 25*^C, GE 2D102, 

available from Newark Elec, 500 N5, Pulaski 
Rd,, Chicago IL, part no. 30F1 131, Si. 60 

T1 Audio Transformer - 5200CT:22,OOOCT: 

600CT, known asW2EWL SSB transformer. 



\ 
I 
t 
I 

I 
r 

f 
I 

i_ 



NEATER 

C6) tS OHM 
2 WATT 




I 



OCTOBER 1969 



55 




The thermistor can be seen mounted on the 
inside of the Minibox oven. Paint was re- 
moved from the box where the resistors are 
mounted. An unpainted box would be pre- 
fersbfe. 

fier creating an audio oscillator. The voltage 

level from the oscillator is converted to a dc 
voltage by the detector, A dc amplifier rai- 
ses the power level to a maximum of about 
25 watts to drive the oven heater. As the 

heater warms the oven and the thermistor, 
the bridge is brought back to balance by the 
lowering of the thermistor resistance- If the 
thermistor resistance is lower than that of R, 
negative feedback occurs around the ac ampli' 
fier and no oscillation will exist. In this way, 
power is applied to the heater only when the 
temperature of the oven case is less than the 
desired temperature. 

Between the point of no oscillation of the 
ac amplifier and full cUpped oscHlation, there 
is some voltage level that allows the heater to 
supply exactly the heat lost from the oven. 
Rather amazingly^ this feedback airangement 
will eventually find this balance point and 
bring the heater power to a constant level. 
Typically, this takes about 30 minutes. 

The actual circuit uses two 2N167 transis- 
tors in the ac amplifier, and two 2N404's 
and a 2N174 in the dc ampUfier* These par- 
ticular transistor types were used because 
they were readily available* Almost any simi- 
lar type should perform satisfactorily. 

With the components shown, oscillation 
occurs at about 800 hz. A full wave detector 
provides a maximum of about 8 volts to the 
dc amplifier. This amplifier uses three emit- 
ter followers for unity voltage gain, with a 
current gain of about 20,000. The heater is 
built from six 15 ohm^ 2 watt carbon resis- 
tors in parallel. 

Construction 

The layout is not at aU critical. A heat 



sink of about 8 square inches area was used 
onthe2N174. 

A standard 2^3/4"x2-l/8'*x 1-5/8" Mini- 
box (Bud CU 3000 A) forms the walls of the 
oven. A 15 ohm 2 watt resistor is fastened 
by a cable clamp on each of the six sides. To 
provide good thermal contact, the side of 
each resistor is fUed flat to a width of about 
1/8". Transistor heat sink thermal compound 
is applied between the resistor and the Mini- 
box, All six resistors are wired in parallel to 
form the heater- 

■ 

In order to minimize tlie time required for 
the thermistor to sense the heater tempera- 
ture, the thermistor is mounted inside the box 
behind one of the resistors. This gives a ther- 
mal lag of about 30 seconds and allows a rea- 
sonable warm-up time for the oven. The 
thermistor is carefully soldered to a ground 
lug that is then electrically insulated from 
the side of the oven by a mica washer. Again, 
heat sink compound is used to increase the 
thermal conductivity. 

Operation 

The only initia! adjustment required is the 




TIME - MINUTES 



Fig, 3, Oven warm-up characteristics. Tem- 
perature meastiremertts were made at the 
center of the oven* 



phasing of Tl . If oscillation does not occur, 
or if operation is very erratic, the 600 ohm 
winding connections should be reversed. 
Normal operation is iQdicated by a warm-up 
characteristic similar to the one shown in the 
graph. 

The oven should be enclosed in an insula- 
ted box. This reduces both the heat loss and 
the magnitude of harmful transient events 



56 



73 MAGAZINE 





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• Zero bias— no bulky auxiliary power supplies. 

• May be used in instant-on, no warmup amplifiers, 
for home brew linears. In most instances the 
572B/T160L directly replaces the 81 lA providing 
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DC plate voltage 2750 volts 

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Filament power e^av® 4.0 Amps 

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such as cold breezes. A 1" to 2" layer of 
foam rubber or fiberglass is adequate insula- 
tion around the oven. 

The contents of the oven should not touch 
the walls- Components inside the oven are 
best mounted by a thermal insulator such as 
foam rubber. 

By adjusting R, the temperature in the 
oven can be set to almost any temperature a- 
bove the ambient. The maximum tempera- 
ture attainable is limited by the 25 watts de^ 
liverable to the oven. If the oven is well in- 
sulated from the air this can mean tempera- 
tures over 100* G so be careful or you may 
melt your new precision standard! Even 
above about 75* C some components may 
deteriorate. The oven takes about 30 minutes 
for the insides to warm up to a constant tem- 
perature. As shown in the graph, the heater 
power steadies up in about 10 minutes after 
having considerable overshoot. 

»,W2CLL 

Bibliography; 

1, W, L. Smith, "Miniature Transistorized Crystal 

Controlled Precision Oscillators/' IRE Transactions 

on Instmmentation, September 1960. 

2- C- K, Klinart, "The Thermistor /' 73 Magazine, 

November 1968, p. 78, 





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OCTOBER ISeS 



57 



■■■IP 



Donald Mead W2LT 
235 South Irving Street 
Ridgewood, NJ 07450 




Crystal 




Phasing 




They can make friends enemies, and 
enemies friends^ by philters/' The Anatomy 
of Melancholy, Burton, 1621. 

Yes, even back in the 1600s, it seems 
they were using filters . • • er, phiJters, that 
is . * .* to perform useful feats of magic. And 
what better legerdemain can be found in the 
modern communications receiver than a 
crystal philter , . . filter, I mean. 



o 




[o] 



O r. O 



Fig, 1, Front view of the unmodified capa- 
citor, 

A crystal filter is useftil in improving 
receiver selectivity because of its ability to 
pass one frequency while attenuating all 
others. It has another useful attribute as 
weU - its ability to null out a specific 
frequency near the acceptance frequency. 
The use of a phasing control permits the null 
frequency to be varied slightly so that a 
near-by interfering signal can be eliminated 
without unpeaking the desired signal 

Although the control described was used 
in the **Second Chance*' circuit,* it can be 
used in just about any standard if crystal 
filter circuit with untuned grid. The phasing 
control, which is simply a three-plate van- 

*"A Second Chance Crystal FUter foi the 
BC-348", 73, June, 1966. 



able capacitor^ is mounted and wired in 
place of the rotary "crystal on-off ' switch 
on the front panel of the BC-348. The 
problem is — try to find a small variable with 
an insulated rotor shaft in any of the parts 
catalogs! After much looking^ we became 
convinced that the only way we could get 
what we needed was to make one. The 
victim was a small AFC variable capacitor 
with a short slotted shaft and locknut. These 
have been a drug on the surplus market for 
years and can be found very cheap. Figs. 
1—4 show details of the modification. 
Surgery is performed as follows: 

a. Remove and discard the locknut. Next, 
with a knife blade or slender screwdriver^ 
spread the four slotted parts of the shaft 
bushing apart and bend them away from the 
shaft. Flex them back and forth until they 
snap off, 

b. Remove the collar from the tip of the 
shaft by filing a slot in the collar. It is 
mounted on the shaft with a force fit and 
can easily be pushed off once it has been 
weakened by filing. 

c* Position The shaft so that the plates are 




Fig* 2. Side view of the onmodified capa- 
citor. 



58 



73 MAGAZINE 





disengaged. Then withdraw the rotor assem- 
bly, taking care not to bend the three-legged 
flat shaft spring (one leg is the rotor con- 
nection termiiial lug). File the rough surfaces 
of the shaft bushing on the front of the 
capacitor until the bushing presents a 
smooth bearing surface. Remove all but the 
two Stat or plates and the one rotor plate 
nearest the ceramic body of the capacitor by 
gently bending the plates back and forth 
until the soldered joint fractures. File or clip 
off the excess portion of the stator plate 
support pins and the rotor shaft* 




Fig. 3. Side view of the nnodifred capacitor. 

d. Prepare an insulating sleeve that can be 
forced over the rotor shaft to receive the 
tuning knob. The sleeve must be 1/4^' in 
diameter and can be about 1/2" in length. 
We used a plastic test prod handle, cut to 
length, that merely needed enlargement of 
the bore down the middle, A No, 21 driU 
makes a hole that fits snugly over the metal 
rotor shaft. The tight fit is important 
because the sleeve must be forced on in such 
a way that the rotor contact spring is 
compressed and the proper spacing between 
the plates is maintained. Incidentally, the 
rotor spring may be flattened a bit to relieve 
some of the pressure it exerts. It need only 
make good electrical contact against the 
shaft shoulder when the plates are properly 
spaced. A smaU metal washer is used 
between the bearing end of the plastic sleeve 
and the filed surface of the bushing to 
prevent abrasion of the sleeve. To assemble, 
place the rotor contact spring in position, 
insert the rotor shaft through the spring and 
bushing, add the metal washer over the 
shaft, and force the plastic sleeve over the 
rotor shaft until the plates are properly 
spaced, noting that the spring is sUghtly 
compressed and making good contact with 
the rotor shaft. This completes the capacitor 
modification. 

The phasing capacitor is mounted on the 
panel in place of the "crystal on-off ' rotary 
switch- The original knob is re-used and 





FIq, 4. Shaft details; (a) before modifica- 
tion, (b) after modification. 

covers the two machine screw heads holding 
the capacitor in place. A small piece of black 
plastic tape may be placed on the back of 
the panel to cover the smaU hole which the 
switch anti-rotation lug occupied- 

By bending one corner of the rotor plate, 
the capacitor will short-circuit itself when 
the plates are fully meshed. This will disable 
the crystal filter and provide normal low- 
selectivity reception. 

One word of caution on connecting the 
phasing capacitor across the crystal — be 
sure you connect the grid side of the crystal 
to the stator* We inadvertently connected it 
the other way first and heard a beat note 
every time we touched the metal knob. It 
turned out that a local BC station, only a 
khz away from the i/ frequency, was getting 
into the if amplifier through the shaft 
insulation capacitance, tiny as it is! Re- 
versing the connections cured this. 

To understand how the filter is able to 
perform this dual role, a small dose of 
theory may be helpfuL First of all, it is 
important to accept the fact that a quartz 
crystal has two resonant frequencies. One is 
the series-resonant frequency, at which the 
crystal offers almost zero impedance; the 
other, about 1 khz higher, is the paraUel- 
resonant frequency, at which the impedance 
is very high. The variation of impedance as a 
function of frequency is shown in Fig, 5, At 
the series-resonant frequency, the crystal 
acts like a series-connected coil and capa- 
citor. L-C combinations Uke this are useful 
as wave-traps to short-ckcuit undesired fre- 



HIGH 



IMPEDANCE 



LOW 




1 



I 



Fig. 5. The variation of impedance as a 
function of frequency. 



OCTOBER 1969 



59 



quencies in the output circuit of a trans- 
mitter or in the input circuit of a receiver, 
for example. On the other hand, the crystal 
also looks tike a parallel-connected coil and 
capacitor at a slightly higher frequency. The 
crystal in the grid circuit of a conventional 
crystal oscillator stage makes use of this 
configuration. Almost everyone is familiar 
with the fact that the frequency of a crystal 
oscillator can be lowered slightly by 
shunting a small trimmer capacitor across 
the crystal . . , a point to keep in mind. 






^^ 



)l 

Fig. 6, The equivalent "black box" electri- 
cal circuit. 

How can the crystal do two things at 
once? Let's take a look at Fig, 6 which 
shows the equivalent "black box" electrical 
circuit. It is clear that Cx and Lx are 
arranged in a series circuit. However, Ch, 
representing the capacitance of the holder 
and ^ wiring, is shunted across Cx and Lx. 



Lk 




Fig, 7. The pdratlef resonant combination. 

Redrawing it^ as shown in Fig. 7, reveals the 
parallel-resonant combination. Considering 
the series-resonant condition, the presence 
of Ch has little effect on the resonant 
frequency; all it does is to act as an 
insignificant by -pass capacitor. However, in 
the parallel-resonant mode, Ch exerts a 



XTAL 



MIXER 



6 



«FC 




Fig. 8. Conventional brfdga circuit with the 
phasing capacitor adjusted to balance out 
the holder capacity. 



definite effect on frequency. If the value of 
Ch is increased slightly, the parallel-resonant 
frequency of the crystal will be lowered 
slightly. 

In the conventional if bridge filter circuit, 
shown in Fig, 8, the phasing capacitor, Cp is 
adjusted to balance out the holder capacity 
Ch so the crystal will pass only frequencies 
at which it is series-resonant Cp can be 
varied slightly either way from the balanced 
condition to indirectly affect the parallel 
resonant frequency of the crystaL Another 
way of doing this, especially in the BC-348 
receiver, is to connect a small variable 
capacitor, Ca, directly across the crystal to 
permit small increments of the holder capa- 
city as shown in Fig, 9, If trimmer Cp is set 
to balance out the holder capacity plus, let's 
say, half of Ca, then any change in Ca will 

cause Cp to have a surplus or deficiency of 
capacity as far as balance is conr 

cerned — exactly the same effect as if Cp 

was the variable control 



Mt)(£R 




RFC! 




Fig* 9. A small variable capacitor is con- 
nected directly across the crystal to permit 
small increments of the holder capacity. 

A word about if alignment is in order. 
The BC-348 selectivity curve with the filter 
out is as wide as the proverbial bam door. 
To make things worse, the if transformers 
are slightly overcoupled, making for a 
double-humped response curve. Originally^ 
we felt pangs of sympathy for the designer 
who had to accommodate both the beacon 
band and the hf bands, with the result that 
the if landed in the be band. But to 
deliberately broaden the selectivity that 
much! No doubt the military wanted a 
receiver that stood a chance of getting the 
message through when tuned roughly to a 
spot frequency. 

The rough alignment can be made on 
background noise. With, the bfo on and the 



60 



73 MAGAZINE 



crystal filter in, advance the phasing con- 
denser until it is half meshed. Then adjust 
the trimmer Cp until the noise has a tinny, 
rin^g sound. Then peak up the if trans- 
formers (top and bottom) for the loudest 
noise with this characteristic sound. TMs 
completes the rough adjustment 

For the final if alignment, you will need a 
stable signal generator, preferably one that 
can be modulated. We found that the vener- 
able BC-221-AK is perfect for the job. Also, 
you will need an ac voltmeter (say 0-5 V) 
that can be bridged across the audio output 
as a tuning indicator. The object of the 
exercise is to find the exact series resonant 
frequency of the crystal After this has been 
determined^ the signal generator is parked on 
this frequency, and the final adjustment of 
all z/ transformers is made. 

Couple the signal generator to the mixer 
grid through a gimmick condenser made by 
twisting two pieces of insulated wire to- 
gether so they overlap for about one or two 
inches. The end of one wire can be stripped 
and wrapped around pin 5 of the 6SA7 
mixer tube which is then replaced in its 
socket Tune the signal generator slowly 
through 915 khz (with the modulation on 
and the bfo off) and carefully adjust the 
frequency for a maximum on the audio 
output meter. If you have hit it on the nose, 
the phasing control can be varied ±10 
degrees rotation without appreciably 
affecting the output. Peak up the if trans- 
formers. Repeat the procedure to double 
check the alignment A couple of hints: use 
no more coupling from the signal generator 
than is needed for a good output indication 
so the // chain won*t be overloaded; also, 
short the antenna binding post to the ground 
binding post to prevent the reception of 
spurious signals which may interfere with 
the desired signal from the generator. 

Before disconnecting the alignment set- 
up, try testing the action of the phasing 
control in nulling out a weak signal near the 
peak frequency. Detune the signal generator 
about 1 khz higher than the alignment 
frequency. Slowly tune the phasing control 
until the output drops drastically. This 
adjustment is very critical and takes a fine 
touch. You should get at least 15 — 20 db 
attenuation as the signal drops in the rejec- 



tion slot. Try other offsets from the align- 
ment frequency; at least one setting should 
result in almost infinite rejection as the 
phasing control is tuned through it* 

When operating the receiver in the "single- 
signal" mode, the phasing control is usu- 
ally set so audio images fall in the re^ 
jection slot, That is, the bfo is set to a 
desired pitch that corresponds with the 
crystal filter peak frequency; Then, the 
receiver is tuned to the same pitch on the 
other side of zero beat The phasing control 
is then adjusted to eliminate this signal (the 
audio image). In this way, half the potential 
interfering signals are automatically elimi- 
nated whenever the desired signal is tuned in 
on the crystal filter peak. 




90e 9L0 9I£ 914 916 



916 9S0 ^ZZ 



Fig. 10. The before and after if response 
curves. 

The proof of the pudding is, of course, in 

the ability of the receiver to dig that rare DX 

out of the pile-ups. Using a homebrew 

converter which translates 10, 15 and 20 to 

the 80 meter band on the BC-348, we 

worked 20 new countries in two weeks- For 

the more scientifically inclined brethren, the 

"before" and "after" if response curves are 

shown in Fig, 10, Need we say more? 

. . . W2LT 



OCTOBER 1969 



61 



^ 




Grounded 




Ralph S. Yeandle, W2IK 

P. 0. Box 252 

Schoharie, New York 12157 



Filament Chokes 



During the course of const ruction of my 
linear amplifier employing two type 4-400 A 
tubes, the market price of a 30 ampere 
filament choke was suddenly raised from 
about $9 to around $25, Whether this was due 
to the high price of copper, the enamel on 
the wire, or because a beautiful doll needed 
a new diamond, did not interest me one iota. 
It was high time for ingenuity to be sum- 
moned forth. 

A look at the driving impedance of those 
tubes in this type of operation indicated a 
value of 300 to 500 ohms or thereabouts, 
which was halved for two tubes in parallel 
This meant that the choke impedance at the 
lowest frequency to be used should have a 
value of, say, five times this in order to 
maintain a low r/loss through the choke. So 
we are then talking about a choke imped- 
ance in the order of 1000 ohms- One could 
wind this kind of a choke with his eyes 
closed unless he considered the current 
requirement of the tubes. This required a 

very heavy wire, size No. 8 or No, , 1 0, and 
even then a good fraction of a volt could be 

lost between the filament transformer and 
the tubes. When a coil takes on these 
proportions, there must be a better way than 
rolling your own. 

The solution was easy. Mount the trans- 
former on insulators at least Va" thickness, 
thus isolating it from all chassis grounds. 
Then connect the secondary directly to the 
tubes using wire of sufficient size to prevent 
any appreciable drop in voltage to the tubes. 
If you find that the transformer has an 
electrostatic shield, as did mine, discormect 
it and let it float. The secondary center tap 
may be connected through a choke to 
ground by employing one of those small 
multiple-Pi types, but if you are particular 



about getting too much dc resistance in this 
circuit, and about wasting a good high 
impedance choke where it is not needed, 
then here is a place where a simply con- 
structed device can be used. One of quite 
adequate characteristics can be made on a 1" 
diameter form about 3" long, wound with 
about No. 30 wire. A primary choke in the 
110 volt line was wound in bifUar fashion 
with No, 24 wire, T* diameter and about 
4¥i^ long. The heavy capacitance existing 
between primary and secondary, coming 
about either by direct coupUng or via the 
core, indicates that there is little difference 
in the magnitude of the rf voltagje on either 
winding and therefore the same amount of 
choke impedance is needed for each. 
Formex insulated wire was used on the 
bifilar and no indication of breakdown 
between adjacent turns has been evident in 
the three years of use* If preferred, two 
separate line chokes may be used in the 
primary in which case each can be physically 
smaller than the bifilar, A .01 mfd by-pass is 
used from each side of the line to ground, on 
the line side only. The above dimensions are 
approximate and have served well in my 
amplifier throughout 80 to 10 meters. They 
were duphcated more or less for another 
amplifier using 2 type 8 1 3 tubes. Of course a 
high quality coil form may be used, but in 
this case the circuit impedance is sufficiently 
low to allow an old broomstick, hammer- 
handle, or a dried out sapling to be 
used - even at 1 meters. 

So the $25 with which I almost parted 
was used for much more important thin^. 
Come to think of it, I believe that I bought 
an anti-gravity machine from a door-to-door 
salesman, 

. . W2IK 



62 



73 MAGAZINE 






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n 



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63 



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with Style 



Most experimenters and homebrew equip- 
ment builders settle for commercial cabinets, 
boxes and chassis to house their electronic 
creations. This article will describe a method 
of building cabinets that are simple and 
stylish and that can be built in a wide range 
of sizes. These cabinets have minimum cost 
and yet have the good appearance necessary 
to make your radio room and workshop 
look highly professional. 

The solution to the cabinet problem is to 
build wooden cabinets like those shown in 
the photographs. Considerable development 
has gone into these cabinets. At this point I 
feel that maximum simplicity has been 
achieved without sacrificing utility and style. 

The accompanying drawings and the text 
that follows describes a **type" of cabinet 
rather than a specific cabinet. If this type of 
cabinet is attractive to you, a little fore- 
thought is in order so that you may adapt 
the design to your own needs and to the 
most readily obtained materials. The width 
dimension will vary depending on the equip- 
ment that is to be housed. On the other- 
hand, perhaps you will want to standardize 




T 





ri 



l/Z 



. I 

r1 



' 1 

1 L ± 



r 



TOP UtEW 
- W 



T 




fSOMETRfC 
VIEW 



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± 



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1~ 
1/4" 



^ . 



3/4" 



t/4" 



T 



2} 

3/4 15^41 1*1^4" 
RftNEL STOPS 




FROWT VIEW 



SIOC VIEW 



SCREW INTO 
PANEL STOP 
(If l«CE5SARYy 



PANEt ATTACHMENT 
SCREWS 




REAR COVER 
AS APPROPRIATE 



SECTIONAL VIEW 



on the height and depth of your cabinets so 
that they will present a uniform appearance. 
The quarter-inch plywood recommended for 
the sides of the cabinets will provide plenty 
of strength for even relatively large cabinets. 
However, if you have a source of another 
thickness or another material, it can proba- 
bly be used. 

Building Suggestions 

The quarter-inch plywood sides and top 
and a three-quarter-inch pine or fir base 
materials appear to be an ideal combination 
of availability and usefulness. It is suggested 
that these materials be cut on a table saw if 
one is available- A table saw will provide 
square, relatively smooth edges that can be 
assembled without further furnishing. So 
little cutting is required that any friend who 
has a saw should be glad to make the pieces 
for you. Cut the sides and top from a single 



64 



73 MAGAZINE 



piece that has been cut to the finished depth 
dimension. This will assure that the top and 
sides are aU the same depth and that they 
will match perfectly when assembled. 

The panel stops in the upper corners may 
be glued to the top of the sides as the first 
assembly step. Use white glue and half-or 
three-quarter-inch brads to fasten the various 
parts. Next, attach the sides to the base and^ 
last, attach the top- Use the white glue 
generously, but wipe any excess off exposed 

surfaces with a damp rag. When the glue is 
dry — about an hour, the exposed surfaces 
should be sanded to eliminate any ridges 
between the sides and the top and to provide 
a smooth surface for finishing* A belt sander 
is handy for this operation, but hand sanding 
is easy and adequate. 




The assembled cabinet should be sealed 
with shellac or a commercial sealer. It can 
then be spray painted using one of the 
quick-drying enamels or lacquers that come 
in spray cans. Build up three or four coats. 
Each individual coat should consist of sev- 
eral light sprays with special attention (re- 
sprayings) being given to any spots that 
tend to soak up the paint. Allow at least a 
half-an-hour between coats even though the 
label will claim that the paint ''dries in 
minutes". The last coat should provide a 
high-gloss finish that will be an asset to any 
shelf in your house. 

Nothing has been said about choosing the 
color for your cabinets and very little will be 
said. However, don't overlook the possibility 
of choosing one or more bright colors that 
wlQ fit with your decor. I use a "mix- 
and-match" scheme. In the workshop, 
cabinets are "color coded'*. Power suppUes 
are red and test instruments are black. The 
speaker that goes with the commercial re- 
ceiver in the radio room is black like the 



negatives for 

p. c t 




BIGELOW ELECTRONICS 
BLUFFTON OHIO 45817 



receiver. 

Panels may be metal, wood, "hardboard 



»i 



or a plastic such as Bakelite depending on 
the needs of the equipment to be housed in 
the cabinet. Hard Masonite with a couple of 
coats of a sealer like Firzite makes an 
attractive looking panel that is easily worked 
using wood tools. 

Panels for speaker cabinets can be made 
from perforated metal or with openings and 
grill cloth in the accepted manner. The back 
of a cabinet may be left open; closed tightly 
with wood or metal; or it may be closed 
using perforated metal or screening. 
Openings in the back and sides may be 
provided for cooling. Heating of the cabinet 
top can be lessened by cementing a piece of 
aluminum foil to the inside of the top. 

The front panel can be mounted in most 
cases by using three-quarter-inch round- 
head-wood screws through the panel into the 
three-quarter-inch base. The panel stops at 
the top will prevent the panel from being 
pushed in. If added security is desired, wood 
screws can be used in the upper panel 
corners. If an extra long cabinet is built, it is 
recommended that an additional panel stop 
be installed on the inside of the top at the 
center of the cabinet- 
Uses 

Cabinets of the sort described herein may 
be used for many types of devices. 
Power Supplies 
Timers 
Speakers 

Signal Generators 
Bridges 
Clocks 
Chargers 
Meters 
Receivers 
Transmitters 
Standing Wave Meters 
Intercoms 

The list above is just a fraction of the use? 
that can be found- These cabinets free the 
equipment designer from size limitations 
and, at the same time, provide him with a 
source of easUy made cabinets that wil 
enhance the appearance of his equipment. 

...WIOLF 



OCTOBER 1969 



65 



Richard X Zach WB2AEB 
33 Pike Place, RFD'4 
Mahopac, New York 1 0541 



VHF - FM : 



Part 




Advantages and Practices 



When you operate, what do you want in a 
system? You may say reUability, quality of 
equipment, as well as ease of operation. 
Perhaps you have as insatiable tliirst to 
tinker with equipment to get the absolute 
best performance, VHF-FM can satisfy all 
these requirements and more. 

As you may know, VHF-FM is growing 
faster than any other mode. Why has such a 
relatively new concept enjoyed such popu- 
larity? Perhaps we can answer this by asking 
still another question. What is VHF-FM? Of 
course, you could say that you FM a VHF 
transmitter. But VHF-FM (or just ^TM" 
from now on) is also an enthely different 
system of communications. 

About 75% of aU FM activity is operated 
from the mobile. The rigs are surplus gear 
taken out of commercial service (taxis, 
police cars, fire trucks, etc). When you 
purchase these rigs, they come with aU 
accessories . . . transmitter, receiver^ power 
supply, mike, speaker, control head and 
cables, but less crystals and antenna. They 
seldom run over 60 watts, with most rigs 
running 30 watts or under. Antenna 
polarization is always vertical, FM deviation 
is usually wide-band (±15 khz) but there are 
a few scattered narrow-band outfits (±5 
khz). The trend today is toward narrow- 
band operation, though. You can get a 
complete rig for as little as $25, but the 
usual price runs between $40 and $90 when 
obtained from a dealer. The possibility of 
obtaining the used equipment directly from 
the commercial user should not be over* 
looked. 

As noted, just about all FM activity is 
crystal controlled and hence, operates on 



'channels.'* Because of accepted channels, 
repeater stations can be utilized. Such 
repeater stations, usually located on high 
ground with higher power, receive signals on 
one frequency and simultaneously retrans- 
mit the received signal on a different 
frequency. Going through a repeat er, you 
can cover a 50 mile radius using just a one 
watt walkie-talkie. However, in speaking 
with other hams, I find that there is one big 
misconception about FM, It seems that quite 
a few people think that you must go through 
a repeater. Quite to the contrary. As a 
matter of fact, m southeastern New York^ 
most FM activity is "direct/' without the aid 
of a repeater. 

Another advantage of channelizing is that 
most stations can, and do monitor. When an 
FM'er gets out of work, on goes the mobile 
rig- When he gets home, on goes the base 
station. After a while, you know when 
the different stations are monitoring. You are 
now approaching the reliability of the land- 
line via ham radio. 

Emergency communications is one of 
FM's strongest points. The fact that all 
stations are always on frequency and FM 
receivers are not susceptible to lightning or 
ignition noise provides for an extremely 
reliable situation. With some repeaters, if the 
commercial power fails, an emergency 
generator automatically kicks in. The abun- 
dance of mobile and portable equipment as 
well as the fact that much of this was 
designed originally for emergency use, gives 
FM the upper hand in most any emergency. 

Operating procedure on channelized FM 
is somewhat unique. In some parts of the 



66 



73 MAGAZINE 





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country, the commercial "lO-code" is used. 
This does provide for quicker QSO's, but 
this aspect of operation has not been used to 
any extent in the New York City area as well 
as many others. "CQ" is never heard on FM^ 
since there is just no need for it. All stations 
are on frequency, so no long call is needed. 

You might simply say, "This is WB2AEB 
monitoring nine-four/' and that's it. If 
anybody wants to gab, theyll answer. Since 
the channels are well known, when referring 
to them you simply say the numbers to the 
riglit of the decimal point. Thus when you 
refer to 146.94 rahz you say "nine-four." 
When referring to 52,525 mhz you say 
"five-two-five.** 

Even where six-meters AM may reign king, 
two-meters is often where the FM ham stays. 
On a national scale, two-meters is also the 
most popular channelized FM band. 146,94 
is the national two-meter frequency with 
other side channels such as 146,76, The 
national 6-meter frequency is 52.525 mhz, 

m 

There is also a national ten-meter frequency 

and this is 29.6 mhz. There are about 300 

hams on this frequency and more are joining 

every day. This band is popular because the 

skip comes in more often than the VHF 

bands. To get on ten-meters FM, you simply 

tune the rig down to 29.6 mhz instead of 

52.525 mhz. The low-band rigs tune from 25 

to 50 mhz often with few modifications. 

As for UHF^ the % meter band is popular 

for your own "secret" repeater. To the 

FM'er, six-meters is called *iow-band," 

two-meters is called ^*high-band," while the 

% meter band is called **450" or simply 

'^UHF," 

As you can see, FM is different. 



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MH 



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I 



I 



OCTOBER 1969 



67 



1^ 



MMH 



Bring Back 



Robert L. Greneli; ex WSRHR 
3926 Beech Street 
Cincinnati, Ohio 45227 





Multiplier 



Some fifteen or sixteen years ago, in 
another amateur publication of which 
Wayne Green was editor at the time, the 
Q-Multiplier was introduced. It ijnmediately 
caught on big, and Heath began marketing a 
kit version which went tJturough several 
models before it was recently dropped from 
their line. Except for its use in certain 
receivers as a notch filter, it has now just 
about gone out of style with the ham 
fraternity. 

It*s too bad that this has happened^ 
because a Q-MultipHer can still do things no 
other circuit can for the same price. It is 
capable of a variety of functions which 
would otherwise require much more compli- 
cated and critical (and expensive!) circuitry- 
No other single circuit of such simplicity and 
low cost offers such a desirable combination 
of functions: L Single signal cw selectivity; 
2. Tunable rejection notch; 3, Continuously 
variable selectivity; 4. Bandpass tuning. 

How It Works 

If all this sounds good to you, let's take a 
minute to examine the Q-Multiplier's prin- 
ciples of operation. Normally, more or less 
by tradition, the Q-MultipUer has always 
been set up to work with a 455 khz if. 
However, with proper modifications to the 
tuned circuit, it can be made to operate well 
at any frequency under 10 or 12 mhz. 

The principle .of the Q-Multiplier is 
similar to a suck-out trap, but considerably 



more sophisticated. When used to peak a 
single signal, the high-Q tuned circuit in 
parallel with the receiver's first if stage is 
regenerative because of positive feedbacks 
This narrows the receiver bandpass. Effec- 
tively, the triode amphfies the high Q of the 
tuned circuit. A signal passing through the if 
at the tuned circuit *s resonant frequency 
sees a very high impedance, and thus passes 
by the Q-MultipUer more or less unaffected* 
A signal slightly off resonance, however, is 
sharply attenuated, since it sees a low 
impedance, and is shunted to ground. 

In the notch or rejection function, nega- 
tive feedback is introduced by the second 



.005 



^3^hr 



27K 



SIA 




RCUR 

1ST if 



1 dFf 

2 BRQAD 
4, fl EJECT 




4TK 



2tj3 



SELECTIVITY 



lOK 

NOTCH DEPTH 



Fig. 1. The Greneli Q-multiplier. LI & L2 
can be either the Heath coils, if you rebuild, 
or Miller numbers 4414 and 4409 respec- 
tively. 



68 



73 MAGAZINE 




triode, causing the impedance/frequency re- 
lationship to be reverse d* Thus, a signal at 
the resonant frequency sees a low imped- 
ance, while those not at resonance pass 
through unaffected by the high impedance 
they see. The sole purpose of LI is to tune 
out the capacitive reactance of the coaxial 
cable used to connect the Q-Multiplier to the 
receiver if. 

With the function switch in the sharp 
peak position, selectivity down to about 200 
hz is available for CW reception. In some 
installations, it may be possible to obtain 
1 00 hz selectivity. 

How to Use It 

The peak can be tuned across the if 
passband of your receiver to sort out a maze 
of signals very effectively. Using the Q-Multi- 
pher in conjunction with a selective audio 
filter is just about the ultimate in effective 
CW reception. You really shave those signals 
close! 1 omitted the broad position in my 
installation, since the selectivity of my 
75A-2 is set by a Collins 2,1 khz filter; but 
for those lacking a filter, the broad position 
is pretty effecth^e for SSB reception. 

In extremely crowded band conditions, it 
is possible to use the Q-MultipUer to separate 
SSB signals. With the selectivity advanced as 
far as necessary, carefully tune across the if 
passband. You'll find you can peak up the 
most essential voice frequencies of the signal 
you're trying to haul out of the mess. Under 
these conditions, the audio is very restricted, 
but you can copy! With a little practice, 
you*ll find that you're able to slice away 
SSB QRM just as effectively as you can in 
the CW mode. 

The rejection function should be famJUar 
to most of you. It works just like a T-notch 
filter or the rejection function of the old 
style crystal filter. Tuning for the notch is 
very critical, and must be done slowly. It is 
also important to adjust the selectivity con- 
trol for the deepest possible notch. This does 
not correspond to the setting for maximum 
selectivity, but falls around the middle of 
the control's range^ The obvious use for the 
notch is the elimination of interfering 
heterodynes and adjacent CW signals. How- 
ever, adjusted for a slightly broader notch, it 
wiU do a fine job of reducing QRM from 
adjacent SSB signals, as weU. In the process, 



you*ll probably notch a good chunk out of 
the signal you're trying to copy, but - again, 
with practice - you'll find it quite effective. 

Building One 

A few months ago, I picked up one of the 
old Heath Q-MultipHers from a local ham, 
tore it down, and rebuilt it in a comer of my 
75A-2. The schematic shows the final cir- 
cuit, except that it does show the broad 
position, which I omitted, for those inter- 
ested. The original circuit used two 
pots — one for peak, and one for reject 
Since the two functions cannot be per- 
formed simultaneously, I used only one pot 
on the panel, and put the pot for the reject 
position under the chassis, since it only 
needs to be set one time, I also changed the 
tuning capacitor from a 100 pfd unit to 50 
pfd to obtain better bandspread within the 
passband. The 100 pfd variable tuned about 
5 khz to either side of the center frequency. 
Those who will be using the broad position 
may want to retain the 100 pfd variable. 

The Miller coils specified will work nicely 
in place of the Heath coils I used. The circuit 
layout is less critical than you might 
imagine, and point-to-point wiring is OK, 
Before making the connection to the plate 
of the first if amp, be sure your receiver is 
accurately aligned. With the Q-Multiplier off, 
adjust LI for maximum signaL Do not 
re peak the receiver if, or you'll degrade the 
Q-Multiplier*s performance. 

With the tuning capacitor at mid-point 
and the Q-MultipIier in the sharp peak func- 
tion, adjust L2 for maximum signaL Repeak 
LI with the Q-Multiplier off and L2 with it 
peaking about 3 or 4 times, as there is some 
interaction. Now check for the performance 
of the rejection function. The tuning point 
of maximum rejection wiQ be just slightly 
different than that for maximum peak 
because of the capacity of the second triode 
switched in the reject function. 

That's it* You should be ready to roU. 
You'U find the Q-Multiplier to be a valuable 
addition to your receiver. 1 hope these ideas 
wiU stimulate some new interest in this most 
useful and versatile gadget. Since Wayne 
Green was responsible for introducing it, it's 
most fitting that he should have a hand in 
re-introducing it ! 

. , . W8RHR 



OCTOBER. 1969 



69 



Gerald Price VP2AC 
Care of Antigua Star 
P, O. Box 114 
St, John% Antigua 
West Indies 



Activation in VP2 



Both in the American phone band and 
the DX section, hams continue to say the 
only VP2s that we have not worked are 
Anguilla and the British Virgin Islands. 
Meanwhile several hams would like to take 
along their rigs while holidaying in the 
Caribbean, Because of this I am writing an 
account of my recent DXpedition to the 
islands. 

A request to VP2MY Frank, the man- 
aging director of Leeward Islands Air Trans- 
port (LI AT) J for a complimentary flight to 
the islands was answered with an immediate 
roger, Frank is a patron of the Antigua 
Amateur Radio Club, 

My next move was then to get a license 
and permission from the St. Kitts Govern- 
ment to operate on Anguilla island, Anguilla 
was a ward island of St, Kitts, but has since 
seceded in June, 1967. 

A telephone call from my home QTH in 
Antigua to the telecommunication officer in 
St, Kitts resulted in my learning that the 
officer had QRT to Canada on business and 
that I should write to the Chief Minister of 
St- Kitts for license and permission. 

A hurried letter to the Chief Minister was 
answered by the Minister of Communication 



1 § ? f ¥3 




Jerry VP2AC making first stop in St. Kitts 
to get government permission to operate on 
Anguilla Island. The rig here is an HW-32 
with a Hustler vertical* 



requesting evidence of my Brit^h nationality 
before consideration of the license could be 
given. 

My scheduled time of departure was too 
short for correspondence, therefore it was 
necessary to call at his office in St. Kitts; 
and after routine inspections of my Antigua 
license, etc., I paid for my VP2K license and 
I was given the call VP2KC* 

About 15 days before leaving on the 
DXpedition, Hurricane Inez destroyed my 
Hygain vertical which was slated for the trip 
with my Hot Water-32. 

An immediate request to New-Tronics 
Corporation in Ohio for a Hustler vertical 
brought a donation of a 4-BTV Hustler 
which I received five days after the request 
via Amateur Radio Center in Miami, Florida, 

On St* Kitts island it was necessary to 
transfer to a smaller aircraft which would 

fly to Anguilla, about 60 mUes north. This 
created an immediate problem — the 6 foot 
by 1 14 inches pipe and the vertical which was 
telescoped to 5 feet 8 inches could not fit 
into the small aircraft, and with only 15 
minutes before QRT time, I hurriedly 
bought a hacksaw blade, quickly cut off 18 
inches of the pipe, reduced the antenna to 
about 5 feet and scrambled into the six- 
seat er. 

On Anguilla island, I booked in at Lloyds 
Hotel, the most elevated location in The 
Valley — the capital or chief town. The hotel 
was the only place too that a generator 
could be rented at a moderate price - there 
being no electricity on the island, 

Anguilla is a fascinating island in the 
northerly Leeward group of the Lesser 
Antilles in the tropical waters of the eastern 
Caribbean- It is a flat island stretching 
eel-like for approximately 15 miles. Prob- 



p 



70 



OCTOBER 1969 




»-* I - 



ill .illlllllllll 



lirfTTfTtpiiMiiiiiiinn 
iiiiiiiilbumiiiuUtii 



Hustler antenna rs being cofinected on top 
of the hotel room in Anguilla Island, From 
this location about 600 contacts were made, 
incfuding WAC and 65 countries. 

ably named L* Anguilla by the French who 
first owned the island, which in now popu- 
lated by about 7,000 people. 

The antenna was ready shortly after I 
arrived, and it was placed on the roof of the 
hotel From here the sea was visible from all 
directions way out to the horizon. In the 
distance 12 miles away was the French- 
Dutch island of St. Martin silhoiietted by the 
sun. 

The generator was set into motion, 
voltage check— 118 volts ac. The HW-32 
loaded ok&y. The American phone band was 
crowded and QRM plus plus. I gave several 
CQ*s which resulted in no reply. 

In the DX section the first station 
logged was VE3BWY Ham with 5x9 sigs 
both ways. Second day on Anguilla the first 
stateside station logged was W2RSJ and then 
the pile-up. AU districts in U. S. A. were 
worked except the 7th district during the 
five-day stay on the island. 

Several VK's were worked every day, in- 
cluding my good friend VK4HR, Harry, who 

was on the lookout for the DXpedition; and 



among the 600 contacts on Anguilla was the 
ever-popular PY2PS, Eva. 

From this QTH WAC was logged and 
surprisingly the Russians were contacted 
long after 1300 Zulu unusual at this time in 
our neck of the woods. 

We regret* that several of the DL*s were 
not worked when they were coming in 5 x 9 
plus about 2000 Zulu, but the generator 
stopped and it took sometime before we got 
it going again. Then conditions to DL land 
had changed, and the DX section was prac- 
tically dead- 

But the American Phone Band was a 
bee-hive of activity. Several stations were 
logged before I found out that I was 
sandwiched between two other DXpeditions, 
VQ9AA Don on Aldabra and FH8JF Hosay 
on Comoro island who were working just 
about 30KC apart 

Tortola in the British Virgin Islands was 
the next QTH of the DXpedition, but before 
QRT from Anguilla I observed that the local 
government was preparing to install 220-240 
volts AC in The Valley. The next DXpedition 
to Anguilla may be much more comfortable 
for the operator. 

To get to Tortola from Anguilla it was 
necessary for one to enter St. Thomas in the 
American Virgin Islands if one wanted to 
travel by air; While booking for St, Thomas 
it was discovered that my certificate of 
vaccination against small pox was missing, 
possibly left in Antigua. 

A quick check with the only doctor on 
the island and I was revaccinated and given a 
certificate. In St, Thomas swift motor vessels 
and sea planes travel to Tortola, and to cut 
down traveling expenses, I packed the equip- 
ment in one of the vessels, and I was happy I 
did because I made a good study of the 
islands. I was amazed with their number and 
proximity. Here, there and everywhere were 
islands — Virgin Gorda, Anegada, Jost Van 
Dyke, Salt Island, Peter Island, Cooper 
Island, Norman Island, Marina Cay, Guana 
Island and many other islands ranging down 
to mere rocks rising from the blue waters. 
We sailed through Sir Francis Drake's Chan- 
nel and tied up to the pier in Road Town 

Harbour. 

The Tortola customs insisted that I pay 
duty on my equipment, but after some 




« 



73 MAGAZINE 



71 



explanation, I was allowed to pass through 
free of duty, pending some further investiga- 
tion into my true mission. 

On Tortola island, the Administrator, the 
Telecommunication Officer and the Inspec- 
tor of Police gave me every assistance to get 
up the station. Thanks to to the Chief of 
Police in Antigua, Mr. Edmund Blaize, who 
sent letters asking for assistance and reco- 
mendation to the DXpedition. Mr. Blaize is a 
patron of the Antigua Amateur Radio Club. 

The capital Road Town is a true valley 
completely surrounded by high mountains 
with an opening from the sea. To my mind 
this location was not ideal for a DXpedi- 
tion — and 1 had decided to QRT to Marina 
Cay three miles away, but this would neces- 
sitate renting another generator for electric- 
ity - and enough money was not available 
for this, therefore I set up station in Road 
Town, and after 5 days operating here 560 
stations was logged. 

Tortola is the largest island in the British 
Virgin Islands with a population of about 
8,000 people who have a strong inclination 
to be Americans, and are greatly influenced 
by their neighbours, the American islands St. 
Thomas, St, Croix and St. John. 

First station logged from Tortola was 
YV2GT sharply followed by WICLX and 
the pile-up bounced in over the mountains 
with amazing 5x9, Another popular YL 
logged in the pile-up was WIRLQ Grace who 
was worked at all the stops as well as from 
the QTH in Antigua, 

Several Africans were worked every day 
after 2000 Zulu- The SM's were constantly 
logged and several HB9s were buried in the 
QRM. My good friend VP7NA Harold from 
the Bahamas was logged and we chewed the 
rag for a few minutes. All the Canadian 
districts were worked, and at the end of the 
Tortola operation WAC was again logged and 
65 countries worked* 

My QSL Manager WA4AYX Pete was 
constantly monotoring the operations 
through the islands, and the courtesy of the 
American hams was indeed commend- 
able — while my QSL Manager and I were in 
QSO, they were all QRX until he was 
through. 

And another commendable factor of the 
Stateside hams was the orderliness in which 



the boys came in when caEed in districts- 
Being transcieve I had to call in the stations 
by districts because of the tremendous 
pile-up. 

My next stop was the island of Barbuda, 
and I had first to return to Antigua. Flights 
to the ward island 40 miles north of Antigua 
were all booked until one week later Having 
only 25 more days of vacation I decided to 
move immediately and boarded a fisMng 
vessel for Barbuda. 

I was the sole passenger and after six 
hours' sailing we anchored m the placid 
lagoon of Codrington Harbour. 

No electricity was available on the island 
and therefore I set up station at the PoHce 
Departmeht with the kind permission of the 
Chief of Police in Antigua, 

The police generator delivered 230 volts 
ac and we stepped down the voltage to 1 16 
volts to power the Hot Water - 32. The 
police officers, some were my schoolmates, 
helped me get up the antenna. We went 
on the air immediately and first worked 
K2CWQ who is believed to be the first ham 
to work Barbuda; there being no record of a 
station being set here before. 

Station K7TNE Meg was worked and this 
was the first and only station logged in the 
Seventh District through the entire DXpedi- 
tion* After 5 days of spotty operation, 480 
stations were logged with a new bird FP8 AC 
on St, Pierre Island, At this moment a YV5 
broke on the frequency and wanted to taJce 
over operation, but I would have none of it. 

Barbuda is a very flat island with high- 
lands up to about 200 feet in the northern 
section of the 62 square mile land. It is 
almost all of coral formation with a very 
large lagoon on the western side which leads 
to the main and only village, Codrington, 
where 1,200 people live like one big family. 

It is one of the few islands where wfld 
deer are still found, and the only island in 
the Caribbean with beaches of pinkish-white 
sands stretching for more than 1 5 miles. 

My QSL Manager Pete has been and is 
still handling the QSL cards for Anguilla, 
Tortola, and Barbuda DXpedition. 

My next DXpedition is being planned for 
Dominica (VP2D), St. Lucia (VP2L) and St. 
Martin (FM7). 

. . . VP2AC 



72 



73 MAGAZINE 




Arnold J. Cain, WB4FDQ 
375 Ruff net Road 
Melbourne, Florida S2901 






It seems now, that my two-meter antenna 
has been up there for ten years, but on 
checking the log, I find it has only been a 

little over two. Of course^ it may only seem 
that way because, in this neck of the woods, 
a lot of hurricanes and high wind conditions 
have tested their strength on this rather frail 
looking piece of gear, I am happy to report 
that it's still doing what its supposed to, in 
spite of them ail! 

The closest we have come to disaster was 
last fall. During a three- week down-range 
trip (I was working at Cape Kennedy as a 
cameraman at that time) Melbourne was 
sideswiped by a small, freak, tornado* On 
my return I found that the two-inch, 
thick- walled aluminum conduit extension 
mast that supports my rotor and hf antennas 
(and which is guyed, top and bottom) at the 
top of my tower was bent at a forty-five 
degree angle from the vertical, leaving the 
antennas facing the ground but otherwise 
intact. 

This small twister had demolished quite a 
bit of valuable property in our town, 
including a beautiful tri-band array at the 
QTH of W4JHM, only a hundred and fifty 
yards west of us* It took me exactly 
thirty-five minutes to saw off the five-foot 
bent portion and get everything back up in 
the air. So much for the rugged ness of this 
kite. 

As you will see, this antenna, even if you 
don't scrounge (as 1 do) but buy all of the 
component parts^ wiU cost almost nothing. 
As for efficiency, I'm sure there are antennas 
you can buy or build that wiQ give you more 
gain, greater front-to-back ratio, etc. 
However, for simpUcity, rugged ness ^ ease of 
construction and compactness, plus broad 
handedness and, last but not least, cost, you 
will have to go far to beat this one. 

One more word on efficiency. I, like most 
of our breed, do not have access to 
high-priced lab equipment, but I do have, as 
you do, friends and fellow hams. K4JKX 




lives about fifteen miles away. Using a 
nineteen-inch ground plane at his QTH, he 
was copying me at less than one half S unit 
on his SR42, while I was transmitting on a 
turnstile at about fifty feet of altitude. After 
switching to my little CR beam, he reported 
S 5-6, a gain of 4^2-5 S units. If this isn't 
good enough performance for you, you*ll 
have to experiment with one of your own. 
So, to work! 

The basic materials for this rig are a 
ten-foot length of 3/4 or 1-inch aluminum or 
steel mast, two six-foot and one eight-foot 
lengths of one-by-two-inch cedar, a 100-foot 
coil of aluminum clothes line, (you will have 
about 25 feet left over) 40 inches of yi-inch 
aluminum tubing, and assorted bolts, nuts 
and insulating material. The 3/4-inch or 
1-inch aluminum tube will be the mast (I put 
my turnstile for local ragchewing, on top). 



OCTOBER 1969 



73 



J 



t^imm 




tOUCAN PUTYOOR 
TURN STILE HERE 



RCFLECTOR ELEMENTS 

H^* EA 

SPACED MAX OF 8' 



ALL WOOD PARTS 
1X2 CEDAR 




50 OHM 
COAX 



3/4''0R I" ALUM. 



Fig. 1. Corner reflector construction. 

Drill holes in the tubing for bolting the 
58-irich lengths of cedar, approximately ISVi 
inches either side of center and drill the 
same size holes (to pass i4 x 4" bolts) in the 
584nch cedar strips about 39y2'* from one 
tnd of each strip (the ends that will form the 
apex). Drill holes, for force fitting the 
aiuminum clothes line reflector elements in 
the cedar strips every 8 inches, measuring 
from the apex or corner end (you may put 
an additional element at the apex if you 
wish — 1 never got around to it). Straighten 
the clothes Une by anchoring one end to a 
tree or other firm object and tugging gently 
but firmly with a car on the other end. You 
will wind up with a nice, straight piece of 
aluminum wire from which to cut your 
49-inch reflector elements. Force the ele^ 
ments into the holes in the cedar strips until 
they are halfway through. I put a drop of 
weld wood glue on each side of each element 
and have never touched them since. 

An important thing to remember at this 
point: don't put the reflector elements in 
until you have layed this out on the ground 
with the reflector frame strips loosely bolted 
to the mast, because you will have to driQ 
another hole in the mast for a bolt to 
support the boom. The boom will be made 
in two pieces so that the director elements 
will be in Une (horizontally) with the driven 
element, and the driven element in line with 



the apex of the comer reflector. To have 
these parts line up accurately, the bolt hole 
will have to be a bit below the center and it 
is much easier to do this with the whole 
assembly laid out on the ground. Once you 
have your holes drilled and are sure of your 
alignment, you may proceed with the 
assembling which wiQ go rather quickly. 

For final assembly, I fastened the mast up 
vertically and bolted the reflector frame to it 
with the elements glued in place and ran a 
thin bolt through the back end of the boom 
and the reflector frame* I put the drive 
element on last. Make sure that you bolt the 
wood strips all on the same side of the mast. 
It looks awfully furmy the other way. 

Finally, the driven element — I must say 
at this point that I make no claims for 
originality concerning any portion of this 
rig — and the drive element is no exception. 
However, in self defence, I have found that 
combining these various components in this 
particular way may be a bit original. The 
driven element has been written up before, 
under different titles. Finding it to be all it 
was ever claimed to be, I am using this feed 
on all of my antennas. Construction is 
ample, quite weather proof and gives me an 
SWR of 1.5-1 across most of the band. The 
whole element consists of a half wave dipole 
of^ Vi inch aluminum tubing fed by a 
transformer consisting of a ^4 wave piece of 
RG8U coax-shorted (center conductor to 
outer braid) on each end and weU taped, 
after which the outer insulation is cut at the 
center. The shield braid is cut at the center 
and separated by about 1 inch and soldered 
to about a four-foot length of RG8U. One 
side to the braid and the other to the center 
conductor of the feed line. All joints are 
taped with plastic tape to weather proof and 
then the % wave piece is slipped into the ^A 



COAK 



ORfVEN ELEMENTS 
(/a"XJ9"ALUM TUBES 

f 



t 



/ 



WOOD SCREWS 
BOOM 




LUCITE OR OTHER 
tNSULATING MATERIAL 



3 



t/4k TRANSFORMEU 
tIPISlDE DRIVE JMELEM.I 



COAX 



SOLDER a TAPE 
BRAID 



^^ RG: 

^^ 'fn, 



RGS/U 



TRANSFORMER 




PIPE CLAMPS 



SHIELD 8RA10 SOLDERED 
TO CENT COND 
TAPE WELL WtTH 

PLASTIC tape;- 



BRAID 



CENTER 



1/4 ^ 

OR )9 2* AT t45MC 



Fig, 2. Detaifs of driven element. 




74 



73 MAGAZINE 





wave dipole leaving the four-foot section of 
coax for feed line. 

You can solder your coax feed directly 
without the four- foot piece, but I like the 
convenience of a short length for testing and 
pruning purposes. When I built mine, I made 
each driven element about 19 3/4 inches 
long and mounted them on a piece of scrap 
Va inch plexiglass. Any good H. F, insulating 
material will do, even bakelite, but I prefer 
the high poUsh of the plastic for our salt and 
weather conditions. After mounting the 
driven element, I prune it to 145mhz using 

my grid dipper^ an impedance bridge, and a 
cheap (95c) tubing cutter. The final touch 
up was made by sUding the element back 
and forth for lowest SWR and doing the 
same for the directors for highest front gain. 
The sketches should make everything clear. 
That about does it. f'm sure that if you 
follow the pics and diagrams reasonably 
closely, you will wind up with as good a 
signal squirter as mine. Good hunting on *'2" 
and "73"s. 

, - , WB4FDQ 

References 

"Infinite Impedance Match/' 7S, March, 1963 

p. 20. 

J 965 ARRL VHF Manual, pp. 208 and 225, Figs. 

9-31. 



A Simple Code Oscillator 

This code keyer has a wide range of fre- 
quencies to please the tastes of anyone who 
wants to learn the code. It uses very few 
parts and can be housed in the base with the 
key* The circuit uses two inexpensive tran- 
sistors, one a PNP, the other an NPN; almost 
any type can be used- 



05tJf 




^1- 



330 



SN?33 0^ ANT 
GEN PURPOSE 
NPN TRANSISTOR 



AfyV GENERAL 
PURPOSE PhfP 
TRANSISTOR 



V " 


' < 


p> 


Y 




1 


K 


n 


J 

E 






^^- 


1 5v r 




K 





8 ONM 
SPKR 



M 



A stmpte code oscfUator 

The unit is assembled on a 5 x 214 inch 
piece of phenolic board. All the parts except 
the 1 megohm pot and 27 k resistor are 
mounted on the underside of the board* 

Ray EzeUe, WA8YWK 



CQ CQ CQ deB&W 



B&W 



Coaxial Dipole Antenna 
Connector . . . Rugged, 
Watertight 

Weatherproof^ strong. Aluminum 
liousing, rustproof parts, steatite 
insufation. Dependable connections 
under all conditions. 

#CC50 $6.60 



n 



Coax Switching Sure 
and Easy 

Single pole, 2 position, UHF-type 
connectors, radial mounted. 

#5S0A-2 $1 0.20 

Single pole, 5 position, UHF-type 
connectors mounted on back plate, 

#5906 S1 1.55 



TVI Low Pass Filter 1 KW 

Q5 db on TV bands, 52 ohms charac, imp., 
80-10 mlrs. 11"x3'x2^ 

#425 $22,50 



Write for complete catalog and prices 

Barker & Williamson, tnc. 

Canal Street, Bristoi, Pa. 19007. (215) 7S8-5591 



NEED CRYSTALS? 




Whr. 

DELIVERY 



SPECIALS 






Color TV crystal {3578, 545KHz) wire leads 


$1.60 


4 for S5.00 


lOOKHz frequency standard crystal tHC13/U) 


4.50 




lOOOKH^frepuency standard (HC6/U) 


3.50 




Any CB crystal irammit or receive 


2.25 




Any amateur band crystal {except 80 meters] 


1.50 


4 for S5,00 


Any marine frequency (HC6/U) 


2.85 




8Q metef cyrstals in FT243 holders 


2.50 





We have in stock over six million crystals 
which include types GRIA/AR, FT243, 
FT241, MC7, FT249, HC6/U, HC13/U 
etc. Send 10^ for our 1970 catalog with 
oscillator circuits, listing thousands of fre- 
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(Add 10^ per crystal to above prices for 
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with check or money order to 

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to Jobbers artd Dealers 




CRYSTALS 



2400B CryiUI Dr.. Ft. Myert. Fla. SSMr 



OCTOBER 1969 



75 



^ 



Th 



e 



ARRL 




A. David Middelton W7ZC 

Box 303 

Springdale, UT 84767 



and Amateur Radio 



The Anniiul tnecting of ilic ARRL Board was 
held in New Orleans on May 2^ 1969. following 
several days of informal gatherings, commiltce 
meetings and socializing, 

A serious attempt was made in the early *50s to 
iiold every other Annual meeting in a place away 
from tlie sliadovvs of the Ivorv Tower in the 
Hartford area. Denver '54 and Montreal ^65 are 
two locales of this meeting of the Board and tlie 
no entourage. Tliere may liavc been other travels 
for this important (to amateur radio) affair where 
tlie fate of AR may be decided or at least 
influenced. However, most such meetings arc held 
jiear UO- 

Present in New Orleans were fifteen directors 
and one vice director acting for his ailing director. 
Also present: a clutch of VPs; the General Mana- 
ger-Secretary, the Treasurer and four vice directors 
(who did not get their expenses paid by ARRL) 
and a bevy of HQ personnel. Missing from the 
roster was ARRL's Public Relations Counsel (Item 
101 of the 1966 minutes requests that a study be 
made of retaining PR counsel to attend all Board 
and Executive Committee nieetingsK Also missing 
-any representative of HQ/s technical staff* 

In reporting tlie activities of this meeting, 
material has been placed in associated areas, each 
listed in a tentative '"order of importance'' related 
to the present and future of both AR and ARRL- 
References are made by Item number and are not 
in the order found in tlie mineoed minutes 
prepared and dislributed by the Secretary. Cate- 
gory headings were selected by this reporter. 

Public Relations-A motion (Item 12) passed 
(11-4) that a study of, and recommendations be 
made for, a form of Field Organization which will 
provide contact between HQ and those members 
whose Interests do not presently coincide with the 
interests of the Communications Dept, 

What ever became of the request for a field 
Organization setup -made by a previous Board a 
few years ago? Such a 1". 0. is long over due and 
badlv needed to brins ARRL to the field! 

After extended discussion, during which it was 
almost tabled, Item 39 requests (13-3) that a 
suitable publication be written by ARRL (after 
consultation with reading specialists) directed at 
the 12-16 year old group. 

The idea is commendable. The negative votes 
are inexcusable. 

A unanimous aftlrmative vote (Item 41) in- 
stnicted the General Manager to take steps leading 
to the addition of an 'Introduction to Amateur 
Radio'' course to high school and adult education 
classes, 

TIris too is an excellent idea, but it will require 
heavy follow-up. 

A unanimous vote f after discussion -Item 44) 
instructed the General Manager to periodically 



publish m CJST information on ARRL\ structure, 
including direciors and SCMs, and to include a 
glossary of ham terminology, 

TMs will be excellent PR and should enhance 
relations between ARRL and the AR bod v. All too 
few licenses know what ARRL is all about and 
many care lessl Such indifference does not always 
involve personalities but is often related to ignor- 
ance of basic ARRL concepts, aims and goals. With 
new blood coming into AR, and with the ever 
expanding fields of endeavor in A R, ARRL should 
do a better selling job of itself. 

According to Item 60, a unanimous vote 
requested the General Manager to have the PR 
Counsel prepare material for distribution to pro- 
spective members that will convey the tangible 
value of ARRL affiliation to the individual. 

This idea, together with that immediately pre- 
ceding it, may make ARRL membership more 
meaningful to amateurs, litis PR work is in the 
ri*iht direction since HO has failed to do its iob on 
this- Follow-up is necessary, if it is to succeed. 

Item 81 states that W4GSX will be presented 
with ARRL*s 1969 Technical Merit Award for his 
analysis of typical amateur antennas using modern 
computer techniques, 

\V4GSX's work will be awaited impatiently by 
many who have been looking for a typical antenna! 
Maybe he has the answers! 

Tills reporter (the originator of ARRL's Merit 
Award) is always delighted and proud to see tliis 
Award made b^ some times the Committee has 
passed it over being unable (?) to find anyone 
worUiy of the Award. It should be noted tiiat the 
original motion creating this Merit Award included 
HQ actions to properly circulate news of tiie 
Award to non-artiateur media in order to obtain 
tlie greafest possible PR from the amateur's work, 
which resulted in Ms Award. Such PR has not been 
properly done and much of the value in the 
non-amateur PR- world has been lost. 

The General Manager was requested (Item 87) 
to "'continue an advertising campaign in magazines 
wliich might be read by individuals who are likely 
to have an interest in becoming radio amateurs, in 
an attempt to attract more individuals into the 
amateur service*" 

Such advertisements should be of great value to 
AR and to ARRL. The word ^'continue'* implies 
that such advertising! has appeared. This reporter 
would be grateful for clippings of sucli ARRL- 

placcd ads as so far tliey liave escaped his notice 

with one exception- 
Defense of Amateur Radio Frequencies -The 

Dec. 31, 1968 ARRL financial report indicates 

under ''Reserves -for defense of amateur frequen- 

cies-S62,413.52." 

This is the balance of a SI 00,000 fund tiir- 

nished ARRL's President Hoover. W6ZH, some 



76 



73 MAGAZINE 




years ago and which had become depleted witli PR 
studies and other expenses* 

Item 30 states "on motion of Mr. Chapman, 
unanimously voted {Messers Spencer and Thurston 
abstaining [italics supplied -ADM]) that, in view 
of an announcement of a forthcoming conference 
of the International Teleconimunications Union, 
the Board replenishes the $100,000 fund for the 
defense of amateur frequencies." 

Althougii little has been heard from the original 
SIOOK or the nearly $37K spent to date, this fund 
could become a vital weapon in the battle to 
preserve and protect our frequencies in a world 
that seems determined to take over all low and 
medium high amateur bands in their obnoxious 
spreading of tlieir own brand of propaganda. 

All amateurs should be keenly interested in 
what ARRL does and what it accomplishes with 
this SIOOK fund. Tliis reporter has seen Uttle of 
the results except the Stanford and Waters reports. 
The latter, at leasts was worth it! That, plus some 
HQ staff junkets to foreign lands is what has been 
seen in QST. 

ARRL can afford to spend almost its entire 
resources in order to effect suitable safeguards that 
will help preserve and retain our useage of all 
bands, SIOOK, if properly expended, can do a great 
deal of good for AR! 

ARRL Membership- Item 42 orders that a 
postpaid insert inviting membership be included in 
selected ARRL publications and in QST, once a 
year. 

The necessity for such a Board directive escapes 
this reporter. HQ should have been doing this for 
years. Such a motion, or the need for it, raises the 
question -does ARRL HQ really want ARRL to 
have more members? More members --more work- 
remember? How about an ARRL membership 
contest-with prizes? This idea (Item 42) should 
bring results— if it is followed up, 

QST -A motion to include a propagation 
column in QST was lost when it was tabled (Item 

66) by a vote of 12-4. 

Some will argue that this information appears 
in other publications. True, and some have wide 
circulation, but what about those die-hards who 
read only* QST— and need this information? ARRL 
should serve its membership regardless of other 
publications. 

Item 68 requests a study to secure more rapid 
delivery of QST in 6 -land, KH6, KL7 and all parts 
of US and Canada and requests that the results of 
this study (by the General Manager) be made not 
later than the next Board meeting. 

In by-gone days one could tell the date by the 
arrival of QST, This reporter believes that the poor 
delivery is not the fault of the QST and HQ staff, 
and offers a tliought that perhaps the postal 
employees are delaying QST by reading them 
before delivery! Could be potential amateurs? 
Maybe! If they were ARRL members they would 
get their own copy and thus perhaps speed up 
ours! 

ARRL-FCC Matters-This category is lengthy 
and somewhat confusing* An attempt will be made 
to shnplify the various proposals and their fate at 
the hands of the Board. 

Item 13 requests that ARRL petition FCC to 
permit Conditionals or higher in the KL7, KH6, 
KP4 and USA insular possessions to use phone on 
2L2 to 2L25 mhz» Also^ that ARRL consult with 
lARU regarding a future petition to FCC to permit 
phone on these same frequencies by Extras. An 



amendment withdrew the lARU bit, but the 
amended motion was defeated. No vote count was 
given. 

Item 14 would petition FCC to permit Techs to 
use 29.0-29.7 mhz. This was amended to read 
29.5-29,7. Vote- 14-1 with the Canadian director 
abstaining as is done in matters pertaining to FCC, 

The Planning Committee was instructed (Item 
19) to consider the feasibility of petitioning FCC 

Expand 75-fone to 3750-4000. 

Move SD-Novice to 3650-3700. 

Expand 40-fone to 7150-7300. 

Move 40-Novice to 7100-7150, 

Expand 20^fone to 14175-14350, 

Move 15-Novice to 21100-21200. 

This Item 19 also instructed that a report be 
made by the next Annual Board Meeting. This 
motion was amended to establish liaison with 
lARU to evaluate international aspects of these 
possible changes and to report by the next Annual 
Board Meeting. The amended motion was passed. 
A large follow-up tag, please. Miss Blue! 

IF Item 37 is followed tluough and IF FCC acts 
favorably, devotees of the art of EME, MS and 
other valued VHF/UHF pursuits will be granted 
higher power. 

Note the IFs in that statement. High power 
would tremendously aid important work being 
done by pioneers in the most valuable facet of 
amateur radio yet encountered and which may well 
become our only area of activity in the near future. 

Item 53 requests FCC to make 144-148 avail- 
able for Technicians instead of 145-147. ARRL 
win so petition FCC, 

After aU somebody has to use those highly 
valuable 4 megs! It is assumed the Techs would 
have the same fone-cw regs as others. 

If FCC agrees with the motion made in Item 
55, potential Extras will only have to wait one year 
to take the Extra exam instead of the current two 
years- 
Note the IF. This is a good idea, and let's hope 
FCC likes it. Novices and Technicians wiU benefit 
if the intent of Item 55 is OK'ed by FCC and 
permission is granted for Techs to obtain a Novice 
license without surrendering their present license 
and waiting one year. 

An excellent proposal will be made to FCC that 
a typewriter (provided by the amateur) be permit- 
ted in copying code exams. Item 73 (always a good 
number) covers this but its originator, the well- 
known contester and triple-A CW op» W4KFC, 
overlooked petitioning FCC to permit headphones 
over the ears of aspiring examinees! Any trembling 
gun-shy neophyte will welcome a mill and maybe, 
someday, headphones again^ 

Item 74 (which was passed) requests FCC to 
assign 1x3 (preferred) calls to Extras who request 
and pay the fee, such calls to be assigned on a 
random basis. 

If tliis idea gets FCC*s nod, some Extras may 
get desirable calls. Oh, for the old days of 
call-swapping and initials in your call and aU that 
sort of thing, sans computers! 

MM boys will be pleased if ARRL's support 
(Item 95) leads to FCC*s approval of MM on 7 to 
7.1 mhz. 

AR will benefit if MM is so allowed, as 
MM-working is both exciting and valuable for 
contactees. 

RTTY addicts will probably rejoice if FCC 
grants RTTY operation on 28-28.5 mhz (Item 96) 



OCTOBER 1969 



77 



but this is not likely to be favored by non-RTTY 
ten- meter ops! 

This same Item 96 asks FCC to move *'CW 
only" operation from 1475-148 to 144-144,1, It 
should liave been there long ago. ARRL endorsed 
FCC*s docket 18508 covering tliis item- 

Aithough belatedly^ immigrants to our shores 
will be permitted ham licenses (after filing their 
fust papers) if K7UGA*s bill S-1466 and SJ Res 27 
become law: ARRL approves this (Item 97) bill as 
should all other American amateurs. Reciprocity 
works wonders! 

ARRL HQ Station WIAW-HQ was ordered by 
Item 15 to establish beacon stations on one or 
more VHP bands, as soon as practical, to operate 
at regular hours and on a published schedule. 

This recognition by the Board of the impor- 
tance of VHP in the ARRL programj altliough 
belated, will be appreciated by all amateurs who 
realize the necessity for heavy HQ participation in 
VHF research if ARRL is to keep up with the state 
of the art and advance VHP/UHF; Tliis reporter 
firmly requests that ARRL put an EME station on 
the air, without delay! ARRL HQ should lead the 
way -not foUow the crowd! 

Item 21 would have moved ARRL*s WlAW 
code practice and bulletin transmissions out of the 
Extra Class portions of the bands, but the motion 
was defeated* 

WlAW should be operated on the border (in 
the opinion of this reporter and others) between 
the high and lower class segments, where practicaJ- 
ARRL's argument that WlAW is not a frequency 
standard station may be true, but p^haps the 
Comm. Dept. should investigate I969*type high- 
stability transmission possibilities. Few stations are 
equipped with 25 -khz markers (even if they have a 
c^brator) and WlAW could help them know 
where these borders lie. ARRL could not be held 
responsible for a legal WWV-type frequency ac- 
curacy, but being near the border (a no-mans land 
for the holders of the lower classes of Ucense) 
could be a boon for all. 

Item 49 (debated and finaUy adopted -vote 
14-2) calls for WlAW to make a six months trial 
run of a repeat of the 0230 GMT scheduled code 
practice at 1300 or so, five days a week. 

Why would any director (two did) vote against 
such an idea? Maybe these two did not wish to rise 
at 1300 to improve theij code. 

The ARRL Board has consistently persisted in 
using an irritating practice of "referral to a 
committee for study/^ or other delaying tactics 
when faced witli a sticky problem with vvhicii they 
did not wish to cope or make a firm decision. 

Item 67 is just such a delaying tactic as it 
authorizes a committee to work with the OSCAR 
group and Foothills College in California to investi- 
gate the estabhshment of a joint ARRL/OSCAR 
station at OSCAR HQ, 

Is tliis to be tlie "west coast official ARRL 
station" mentioned in League Lines, June, 1969 
QST or is this to be the $1500 ARRL Space 
Station? 

The Electronics group (plus able volunteers 
from industry) demonstrated their many capabili- 
ties and abilities in the well-executed OSCAR 
pro-ams to which ARRL gave lip service, some 
QST space, and the ARRL Technical Merit Award, 

This reporter believes that a joint 
OSCAR/ARRL station would be Mke the infamous 
"horse-rabbit" meatloaf, made of equal parts, one 
horse and one rabbit. Name the horse OSCAR, 



The idea of a west coast location for either a 
WlAW-type operation or a Space station is merit- 
orious and should implemented without further 
delay! Yes, Virginia, there IS a west coast! 

If this is the HQ's answer to the 1957 (Item 24) 
directive allotting $1500 for an ARRL Space 
Station J then why wait any longer? 

The director of the Pacific Division (in which 
OSCAR HQ is located) is to be commended for his 
fortitude and success in getting a *'study'* ordered. 
But, why a study on a west coast ARRL station? 
There has been a dire need for such a facility for 
many years and it will be welcomed by all who live 
west of the Hudson! 

The Board recognized AMSAT (see June QST) 
and OSCAR by (Item 99) appointing liaison 
directors to these timely and vital programs. 

However J by their omission of N AS TAR they 
indicated eitlier their indifference to the placing of 
a ham repeater on the Moon, or their ignorance of 
NASTAR, or both. 

$1500 for an ARRL Space Station? Many 
VHFers have antennas that cost that much- 
ARRL's stated worth (Dec, 31, 1968) was 
$1,244,288.45! Is ARRL reaUy interested in VHF 
or not? 

ARRL and VHF Repeaters- the modus oper- 
andi of the Board can not be more clearly 
demonstrated than in the progression of a good 
idea to a weak one-as shown in Items 20, 38, 51 
and 89. 

Item 20 (tabled) comprehensive reporting of 
and an interest in VHF repeater operation by HQ 
personnel and in QST space. Item 20 also called for 
a section of the ARRL H-Book to cover VHF 
repeaters and their operations. This motion was 
well organized, vitally needed by those who get 
their Icicks form this newest facet of ham radio, a 
phase that is rapidly growing in popularity and 
usefulness. 

Item 38 (tabled by a vote of ARRL^s President, 
after a tie vote by the directors) called for a 
separate VHF REPEATER handbook to be written 
and published by ARRL. 

In Item 51 the director who made the proposal 
in Item 20 (apparentiy in a desperate effort to 
salvage something from his good idea) amended his 
original motion, albeit emasculated, to request 
QST to carry news of VHF repeater activities in a 
principle subsection of The World above 50 MC: 
This amended motion was then passed. 

The same director then proposed (Item 89) that 
ARRL include a section on VHF repeaters in the 
1970 H-Bk- This motion passed- 

Note that Item 89 calls only for a section in the 
70 H'Bk, 

Your attention Is called to Items 20-38-51 and 
89 as a study in Board procedure, when faced with 
HQ opposition and Board indifference! This study 
should be entitled-'*how to have a good idea 
ruined without really trying!" The reporter is sure 
that ardent VHF repeater fans will have less than a 
huzzah for the Board on this matter. 

Item 61 authorizes the General Counsel to file 
comment and to petition FCC to impliment the 
report of the VHF Advisor>' committee with 
consideration given the status of various related 
rule-making procedures now pending with FCC. 

ARRL-RTTY Matters-ARRL approved (Item 
17) FCC's Rm 132 (pending) permitting RTTY 
operation at 60, 75 and 100 wpm. Good thinking! 

Director A flairs --Several motions were made 
regarding directors, their duties and other matters. 



78 



73 MAGAZINE 



Item 11 called for procedure of impeachment of 
any office holder elected pursuant to the Articles 
of Assoc, the By-laws and the responsibilities of 
his office. This motion passed. Perhaps we may 
now have a method of ridding ARRL offices of 
incompetents, 

At last (Item 58) ARRL directors (not vice 
directors) are authorized to attend ARRL National 
conventions with expenses incurred chargeable to 
authoiixed division aUotmen ts. 

It might be noted that the 1969 ARRL 
National Convention was scheduled for Iowa, the 
home state of ARRL's president. Any connection 
purely coincidentaL 

Why has it taken until *69 to get such a 
worthwhile measure passed? Not many directors 
have the wherewithal to travel on their own 
expense and few can arrange "business trips" to 
permit their attendance at ARRL's own national 
event This motion is worthy and this reporter 
trusts that all directors will take fuM advantage of 
it* 

Item 36 (which passed) is of extreme impor- 
tance! It is also highly significant of what may be a 
new progressive spirit in the Board, 

A Special ARRL Board meeting is called for 
Nov, 1, 1969 to consider or act upon the follow- 
ing - 

1. Actions pending before FCC. 

2p Reports and studies of HQ staff- 

3* Amateur band occupancy, 

4. Committee recommendations. 

5. Establishment of an ARRL Foundation, 

6. Recommendations of Counsel regarding 
amendments to provide for two meetings of the 
Board each year. 

This item also states that any other matters to 
be placed on the agenda may be added up to and 
including Oct. 22, upon concurrence of at least 
nine directors, 

Note that a majority must concur even to get 
an item on the agenda. However, the agenda is 
potentially loaded! 

Item 36 also urged directors to arrive at the site 
of the meeting as far in advance as possible and 
reasonable for committee and informal confer- 
ences. 

This is SOP, allowing several days for informal 
(non-reported in QST) conferences at wliich most 
items are fairly well firmed-up and prepared for the 
''formal*' reportable meeting. This May meeting 
was not marred by *^committee of the whole" 
tactics. Several recesses were called for the purpose 
of discussion, off the record, and other necessary 
rest periods* 

A second meeting each year, if made official 
and acted upon yearly (after '69)^ will be one of 
the most lasting and beneficial acts of the May 
meeting. The ARRL has long suffered from a 
communications gap with a year between meetings. 
This has often resulted in permitting the Exec. 
Co mm. (which meets frequently) to act without 
referral to the full Board or to handle matters 
which should be Board-controlled. 

A single yearly meeting for a megabuck corp- 
oration, is less than justifiable. This demand for a 
second meeting is commended. It is truly a step 
forward in directorship. If directors meeting in 
November wiU study the minutes of the May 
meeting as well as those of recent years and 
foilow^thru on some of the unfinished business 
(tabled or otherwise) something of value may be 
achieved. 



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OCTOBER 1969 



79 



f 




The agenda of the November meeting contains 
controversial items and the meeting should be most 
intriguing! 

rtem 76 lists budgets for administrative ex- 
penses of directors for '69. These amounts are set 
by the individual director v^ho may request any 
amount deemed necessary to spend in the interests 
of ARRL in his division. These amounts range 
from $1000 to $3200. 

With the high cost of travel and printing, it 
appears that these figures are (for the most part) 
puny. There would be no objection if any director 
raised his expense figures although when this 
reporter was a director there was some effort on 
the part of many directors to see just how cheap he 
could be in his directorship, rather than see what 
was needed to really do a job of representation and 
request sufficient money to do the job. 

Many directors must spend money out of their 
own pockets to fulfill their responsibilities and this 
does not seem proper when the ARRL gross 
income is large (1968 -SI, 498,5 74.62) and the 
need for better and more extensive communication 
between director and member is so prevalent. With 
larger budget authority each director could more 
effectively represent ARRL in the field. 

Item 34 provides vice directors with advance 
copies of QST each month. Now, that is a 
magnanimous gesture on the part of the directors- 
At least vice directors get that much out of their 
almost non-existent duties. ARRL officers receive 
no salary. 

One of the motions that can usually be counted 
upon at each Board meeting is contained in Item 
92. This motion called for authorization to permit 
vice directors to attend (at League expense) one 
Board meeting during a two-year term of office. 
This long-needed authorization was defeated by a 
vote of 9 no -7 yes! 

The thinking of those nine directors must be 
fuzzy. Why would not they welcome the presence 
of vice directors at the Board meeting so they 
could see what goes on, first hand, at these 
meetings. Many cannot afford to do this. Vic^ 
directors can only monitor the meetings anyway, 
and have little or no voice. 

Vice directors, could if allowed and encouraged 
to do so, become a vital part of the activities of 
ARRL pohcy-making- But NO! Not only are they 
excluded from such opportunities they are forced 
to either pay their own way or obtain funds 
elsewhere to attend a convention or meeting. It is 
time that vice directors were recognized and 
brought into the ARRL political picture and 
activity to the fullest extent. Their talents are 
badly needed in the field! 

Ironical as it may appear the ill-fated motion in 
Item 92 was followed by a unanimous vote of 
appreciation by the Board for the several vice 
directors present-ad nauseam! Such a motion 
seems rather puerile and in the case of nine 
directors, penurious! 

Electioneering-Items 10 and 70 provide an- 
other example of Board stalling by referral to a 
committee of a sticky problem* 

Item 10 caUs for procedure wherein candidates 
(for director or vice director) would furnish HQ 
written information concerning his qualifications 
(not more than 200 words) and a list of his 
amateur radio affiliations. This material was not to 
contain any derogatory (by innuendo or directly) 
statements regarding any opponent for the office. 
This material to be prepared with a phpto (if 



supplied) in a standard size sheet for each can- 
didate so furnishing the information, and pub- 
lished, with no HQ editing, then enclosed with the 
ballot sent each potential voter. The same item 
provided that no lists of names and addresses or 
addressed envelopes be supplied to any candidate 
or his committee or to anyone for electioneering 
purposes. This motion was tabled by a unanimous 
vote. 

Another stall was made when in item 70, the 
same director presented an almost similar motion, 
albeit shortened, with the same motive. Another 
amendment assigned the matter to the Planning 
Committee for study. This amendment passed 
10-5, The whole idea was then demoted to a 
"study of election procedures by the Committee*' 
by another unanimous vote. 

A uaiform electioneering literature release, with 
the ballot, would be beneficial and would save 
much expense on the part of electioneering groups, 
provided, of course that HQ did not censor or edit 
such material submitted and that no difficulties 
arose as to what constituted '^derogatory remarks/* 
etc. All candidates would therefore have the same 
opportunity for exposure, at less expense, than 
with the present method wliich is unfair in that it 
gives a break to any candidate able to raise 
sufficient funds to widely advertise and also 
deprives candidates not so fortunate, who may be 
just as quahfied for the office. Holding any ARRL 
office should not be contingent upon how much 
money a candidate or liis supporters can raise. 

This reporter hopefully looks for this reform at 
the earliest opportunity. And, that the intent of 
the original motion be preserved, in toto! 

Item 46 is a somewhat confused attempt to 
secure redress through a committee of teUers for 
unfair, unethical or otherwise undesireable action 
by, or on behalf of an opposing candidate. Such 
complaint to be made in writing. A move to table 
was lost as there was no second. After more 
discussion, anoliier tabling motion passed, 12-4, 

The thinking behind tliis motion may be well 
founded but the intricities of handling such a 
complaint would challenge the mind of a Solomon. 
Regardless of that fact* tabling such a motion 
solves nothing and is an indecisive way of handling 
a hot potato but indicative of the lack of direct 
action displayed by the Board on such occasions* 
Sort of reminds one of the Congress! Sweep it 
under the rug, boys, and forget it! 

Communications Department- In Item 59, the 
Board created a five-band WAS award to be 
initiated by the Comm. Dept, and effective after its 
availability. 

This is an excellent award idea and should 
create a lot of interest in domestic operation but it 
is hardly a matter for deliberation by the directors 
of a megabuck corporation. 

Why did not the Comm. Dept. just up and 
create this miracle and put it into use? Perhaps it 
was not their idea at all, and it does mean more 
work for the Comm, Dept J 

Those seeking credit for their personal net 
accomplishments will be pleased to learn that 
ARRL's Comm. Dept, will now recognize (a) net 
check-ins; (b) net control duties; (c) net liaison 
duties; (d) Emergency Corps participation; (e) 
phone patch operation- Points are to be estabUshed 
and reported in QST by SCM$. This motion was 
unanimously accepted in Item 65. 

This reporter is fully aware of the importance 
of certam types of net operation and the training 



80 



73 MAGAZINE 




value contained in some nets and does not belittle 
such activity. It does appear that QST space could 
be better occupied with articles on net operation 
and net concepts of general information to all, thus 
stimulating more interest in and understanding of 
the motives and practices of the better class of 
nets. 

The point standings could be better handled in 
the Comm, Dept. voluminous bulletins sent to 
those interested rather than take away QST space 
from technicaJ and other valuable material. Only a 
few QST readers have interest in traffic matters. 

What a comedown for the Co mm. Dept. to have 
to recognize phone patching and to have to issue 
points for it. Wow! 

Stand by for a cut in readable QST space and 
an appropriation for computer rental! 

The Board, after deliberation, established the 

ICAO phonetic alnhabet (Item 63) as approved 
Now to get the lads to use it-or any other 

standard phonetics. It is unlikely that ARRL 
approval is going to reduce or change the silly 
practice followed by so many with their inane and 
confusing self-established phonetics* 

Item 82 will change the rules -to require that 
candidates for SCM must have been a Full Member 
of ARRL and, to have held a General, Conditional 
or higher license, for two years. 

This is a good move designed to insure better 
qualified persons in this important, unpaid and 
difficult task of being an SCiM, 

Item 83 places the determination of the stand- 
ards of quaHfications for an 00 to be the 
responsibility of the Comm. Dept. Manager. 00- 
— Official Observer-a volunteer Grand Island-type, 
with no authority or back-up to cause operators to 
"fly right." SCM- Section Communications Mana- 
ger-a volunteer unpaid local representative of 
ARRL at state or geographical levet Reports in 
QST and bandies traffic matters for his area. 

Contestees will delight in Item 33 and all others 
(a majority) wiU climb the nearest wall! This item 
proposes a Comm, Dept. party once a year in 
which members are invited to work the Leaguers 
official family of officers or appointees. 

There used to be a similar type contest called 
LO Nite (League Officers Night) and it is sunnised 
that this new bit of QRM-making ** togetherness" 
may be in addition to LO Nite. 

This reporter wonders if certain League officials 
will answer pointed questions during these QSOs? 
Let's find out! 

SCMS and the Board -Item 18 instructs the 
General Manager to furnish each SCM (at his 
request and at ARRL expense) a set of training and 
operating manuals- The SCMs are perhaps the 
hardest working members of the L(3, and they 
must be a real hardy breed! 

ARRL and its AffiUated Clubs-Item 16 (which 
failed to pass due to no second) would have 
furnished a free sub to QST to any affiliated club 
who could produce ten members of ARRL who 
would sign such a request. The loss of this motion, 
due to failure of a second, is lamentable and sure is 
poor PR! 

ARRL and the DXCC-The Board again delved 
into petty non-Board deliberations when (in Item 
47-passed) it permits DXCC members to submit 
QSLs in increments of 10 after 250 countries have 
been credited* A worthy idea-but hardly a matter 
for Board consideration. 

Item 56 attempted to secure a unified countries , 




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list. After several amendments and much deliberd- 
tion the following was adopted -"that the Presi- 
dent and General Manager study the feasibility of 
implimenting preparation of a countries Mst jointly 
prepared by lARU societies." 

This will solve nothing! Many of the important 
countries lists (and awards) are made by groups, 
organizations or publications who aie not lARU 
members. The original motion was well-organized 
and important. Read it in QST and see for 
yourself. It should have been passed without 
debate. Now sometime we may have an lARU list, 
which will be dominated by ARRL's DX clique^ 
and it will be ineffectual! 

In the *50s this reporter advocated and fought 
for a DX committee with representatives of leading 
ham organizations, DX clubs and publications. Tliis 
idea was defeated. Result— utter confusion in the 
DX ranks as to what, where* when is a country. By 
the beaid of TOM-tliis IS a Rotten Mess! 

ARRL Foundation-Item 28 instructs the Gen- 
eral Manager and Counsel to promulgate the 

establishment of the ARRL Foundation, as a 
separate non-profit corporation. Objectives and 
purposes to provide ways and means for perma- 
nently establishing authority to utilize special 
funds and property of the Foundation and income 
therefrom under restrictions as might be imposed. 
(The motion is long and wordy and does not 
coinside with the version given in League Lines 
June QST), The Foundation would be managed by 
a Board consisting of the ARRL President^ Treas- 
urer and Secretary plus other director-elected 
members. 

The basic idea appears to be a means whereby 
ARRL can receive funds (gjfts, bequests, etc.) and 
expend them as a separate corporation from ARRL 
Inc. The outcome of tliis excellent idea will be 
forthcoming in November. 

It is hoped that the Foundation will not be as 
miserly as is the official body of the parent 
corporation when it comes to advancing the state 



of the art of amateur radio and stimulation 

thereof! 

ARRL and Assistance to Foreign Amateurs - 
Item S2 voted unanimously that ARRL continue 
its program of assistance, etc. 

There is no quarrel with this motion except 
that ubiquitous word continue. Study of past 
ARRL affairs reveals little that has been done in 
this line and to continue along the present path of 
'*assistance" does not seem to be of much value to 
anyone, ARRL could and should do a great deal in 
this line-but like many, this reporter believes that 
charity begins at home. Perliaps a communications 
gap exists between HQ and the reader-membership 
or perhaps it is another example of the familar 
phrase— credibility gap! 

Conspicuous by its absence was reference to the 
ARRL Space Station ordered installed under Item 
24^ 1967 minutes J unless Item 67 can be so 
construed as to that station to be located at 
OSCAR HQ. No mention could be found in the '68 
minutes of the Space Station- 

Another matter not mentioned in *69 minutes 
was the ARRL out-going DX CJSL bureau as 
discussed in Item 37 of the *67 minutes, A study 
and report was ordered (Item 17 -'68) and was 
given to the Executive Committee Jan. 1, 1969, 
meeting 325. The committee unanimously voted 
against the establishment of such a bureau conclud- 
ing "that it would be in the best interests of 

amateur radio not to expand the existing system," 

The existing system is that of HQ receiving 
incoming QSLs and sending them to unpaid volun- 
teer bureaus who mail cards to those having 
envelopes on file in the bureau. 

This incoming system is excellent due to the 
hard-working and tireless group of volunteers but 
ARRL (the largest and most wealthy) amateur 
radio organization in the free world should long 
ago have established an outgoing DX QSL system. 

The Executive Committee decision appears to 
be another example of abrogation of responsibili- 
ties by the Board who passed the buck to the Exec. 
Comm. whose record in the past has been toward 
the reactionary side. 

There are at least two out-going QSL bureaus 
doing business at this time. Perhaps DXers are 
better off dealing with "private enterprise" than 
with an agency* especially if it does not want to do 
the job. 

In addition to the above items the Board 
considered and acted upon various other matters in 
one way or another. Most did not seem of 
sufficient import to be reported here, 

A sincere effort was made to preserve the intent 
and meaning of each motion discussed. Although 
some were paraphrased for brevity, in no case was 
any idea or motive deliberately distorted or taken 
out of context. 

Deliberations and decisions of the ARRL Board 
of Directors (as well as those of the Executive 
Committee) affect ALL amateurs and AR. You are 
urged to carefully study the minutes in July QST 
and, with this commentary at hand, attempt to 
reach your own conclusions as to the results of this 
meeting. 

A ball-park estimate of the items in the entire 
proceedings resulted in a tally of 38 that were 
beneficial, in one way or another, to AR, and there 
were 16 that were considered negative. You can 
make your own tally after digesting the minutes. 

. . . W7ZC 



82 



73 MAGAZINE 







Ear! Spence K4FQU 
1413 Davis Drive 
Fort Myers, FL 33901 





Power 




Many of the transceivers on the market 
oday are packaged separately from the 
lower suppUes. The easiest way out is, of 
ourse, to pay the $100 (or so) and buy the 
»ower supply along with the transceiver. 

But if you happen either to be obstinate 
ff hold that $100 in a little more awe than 
eems to be average these days, you might 
/ant to follow my lead and build your own 
>ower supply. 

First, let us examine what is needed in a 
rower supply capable of powering an SSB 
ransceiver of the NCX Class. Most similar 
igs utilize about the same voltages and 
urrents. We find that my rig required a final 
ilate voltage of about 700 vdc at 300 ma 
^hich is maximum current under load. A 
lias of 80 vdc negative at 6 ma, 280 vdc 
upply at 200 ma, and of course filaments, 
nake up the balance of the needed voltages, 
This is not a lot of power and can easily be 
urnished with a good husky TV trans- 
or men The transformer is the most expen- 
ive portion of a power supply and, natu- 
ally, the most important, so care should be 
aken in choosing it. Test the one you select 
o make certain it will deliver under pro- 
onged load without overheating. It is far 
:asier to check before than after the supply 
s finished. Keep in mind that the trans- 
brmer has to produce fuO voltages under 
*EP conditions so the full drain even at top 
oad is not extremely heavy. Therefore don*t 
>verlook a transformer just because it is not 
IS big as a bread box. 



My junk box produced a number of likely 
looking transformers, but none had just the 
light voltages. A Uttle scrounging in a 
friend's junk box turned up one which did. 
It was center-tapped, produced about 750 
volts across the winding and was large 
enough to gamble on its providing the 
needed current. It also had three filament 
windings which are used for the bias trans- 
former and the filaments. The bias trans- 
former is a cheap 6.3 volt fUament trans- 
former and is run backwards off the 5 volt 
winding of the power transformer to 
produce about 100 volts. 

The output high voltage of the power 
transformer was a little over 700 volts using 
a solid state bridge rectifier and the center- 
tap was used for the low B+ supply. Al- 
though theoretically the center-tap should 
have produced about 350 volts, this one 
only ran 300 and dropped under load to 285 
volts • . . just about on the nose. 



1 shows that the circuit is clean and 
straightforward and not of unusual or new 
design. It should be quite easy to under- 
stand, even to those of us with limited 
knowledge. Notice the bias supply in par- 
ticular; This is an easy method of obtaining 
negative voltages and has been used in many 
similar circuits. The output of the reversed 
filament transformer is rectified by a single 
diode of the same type and ratings as those 
in the bridge network. Although I included a 
variable pot in this bias supply^ it is not 




»CTOBER 1969 



83 



SOOvcF 

dt 30O(TH3 

J 



liqVAC 



■xTip- 




+ 700 VDC 
c 



■<r\j>— ' j^ 



T'\ 



+ Z80V0C 



JOflt 
450 V 




fN740 



IIOV 
T-2 



£OMt 
200V 



5K 



O-0OVDC 
— O 



25W 



Uav 



6.3V 



-* iaeV FILS. 



-COMMON 

1 



Fig. 1, The schematic for the cheap and easy power supply- 



needed for the NCX-5 as it has a pot for this 
on the rear apron. Mine was included, since 
the supply is used on occasion as a bench 
supply. You may elect to do without it. 

Physically the supply is small though 
quite heavy (about 35 pounds) due mostly 
to the transformer and the two chokes. It is 
built ona2x8xlO inches aluminum chassis 
with the transformer and two chokes mount- 
ed on the top along with the bridge network. 
It has enough room to include the speaker if 
you wish. Control circuitry, filters and bias 
transformer are mounted under the chassis 
with lots of room for large fingers* All con- 
nectors are brought out one end of the chassis 
and include a nine pin Jones connector, an 
RCA phono plug for the speaker lead, the bias 
pot and the ac line. No switch is required in 
the ac line as this is done in the transceiver; 
however* I have one buUt in for bench use 
which is left in the on position when used 
with the rig (not shown on the schematic). 
The ac line should be fused in each leg per 
standard safety measures. 

The heart of the unit is the diode bridge 
network and a few words are in order about 
the subject. All diodes are the top hat 
variety and are readily available in most local 
supply houses at about 50 cents each. They 
are rated at 400 volts PIV and 750 mil 
capacity. This is a full wave bridge using 
three diodes in each leg or twelve in alL Each 



diode is protected by a re^stor and capacitor 
in parallel across it. Surge resistors are used 
ahead of the bridge in each leg; without 
them you might soon be replacing diodes* 

Mount the bridge network on a small 
piece of Vector board about 2x4 inches. This 
board should be the type on which the lugs 
go through the board on both sides. Mount 
all the diodes on the top side of the board 
running around the board so that it is fed 
from the center on both sides. Ground and 
the dc will be from each end of the board. 
Mount the resistors and capacitors on the 
under side of the board making sure that 
they do not short across the board. Bore a 
hole in each corner of the board and mount 
on 1" stand-off insulators. Be certain that 
nothing shorts to ground or you will have 
smoke! 

The rest of the supply is common sense 
and so nothing more will be said about it. 
Make a cover with Reynolds perforated 
aluminum and paint to match your rig. Take 
care so you can be proud to say that you 
built it. This circuit and supply is not 
offered as the perfect solution to your 
needs, however it will suffice with minor 
alteration for almost any modern 200 watt 
SSB transceiver, 

I have been- using this power supply for 
about a year now without a moment^s 
trouble. It ran the NCX-5 for 24 solid hours 



84 



73 MAGAZINE 





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during last field day and was cold to the 
touch at all times. It just recently ran the SS 
contest and ran cold even after a brief 
exchange with W2NSD/1. The transceiver 
can be loaded to about 60 mils over maxi- 
mum so it is evident that there is plenty of 
current, Plate voltage under full load runs a 
hair imder 700 volts. On the air reports are 
good and it has no noticeable bogies. 

Total investment for all parts that the 
junk box did not supply came to about $18. 
Included among these parts were all the 
diodes, chassis and a filter capacitor. It^s a 
far cry from the $110 plus tax for a 
commercial supply. 

, . . K4FQU 



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i 

I 



OCTOBER 1969 



35 



Getting Your Extra 
Class License 



Part IX 



Modulation 



73 STAFF 



One factor which all forms of communi- 
cations share is ^'modulation." While we 
use the word, in radio, to refer to a specific 
process involved in generating a signal for 
transmission^ it^s used elsewhere with much 
wider meanings - as for example in the 
phrase "he has a weU-modulated voice/* 

Even if we limit ourselves to the meanings 
of "modulation" involved in radio, it's a 
most important subject. A m^or group of 
questions in the Extra Class license examinar 
tion study list deals with various specifics of 
modulation - and that*s our subject this 
time. 

The FCC*s study questions which we'll 
cover are: 

1, What are sideband frequenci^? 
During 100% sinusoidal amplitude modula- 
tion, what percentage of the average power 
is in the sidebands? How is the sideband 
power related to the percentage of modula- 



2, What do the modulation envelopes of 
amplitude* modulated waves with 75%, 
100%, and greater than 100% modulation 
look like? 

18. Define the deviation ratio in a fre- 
quency modulated signal. 

19. What type of signal will be produced 
when the output of a reactance modulator is 
coupled to a Hartley oscillator and multi- 
plied in frequency? 

56. What is a grid-bias modulated ampli- 
fier? Should the source of. fixed bias have a 
high or low internal resistance? Explain, 

63. How are reactance tubes used? 

As is our usual custom, we won*t answer 



these six specific questions directly, Instead^ 
we'll paraphrase them into four questions of 
much broader scope which will cover the 
details involved in the official questions* 

For a starter, we'll attempt to find out 
"What is modulation?** After all, we can't 
very weU examine the details of anything 
until we know what we're trying to examine. 
An adequate definition of modulation , also, 
may help to put the rest of our discussion 
into a proper framework. 

Having defined "modulation," we can 
then ask "What can we do to a signal to 
modulate it?*' This wfll sort out the various 
forms of modulation into appropriate groups 
and, along the way, wfll define the major 
classes of modulation types. 

When we know what we want to do, the 
lo^cal successor in our list of questions is 
how. That's our third one: **How can we 
modulate a signal?" 

And finaUy, having seen how to produce 
modulated signals using any of the major 
classes of modulation which are in wide use 
by hams, we need to examine the charao 
teristics of these modulated signals. Our last 
question this time will be "What are the 
characteristics of a modulated signal?" 

WeVe got a lot of ground to cover to 
answer those four questions; we're on our 
way! 

What Is Modulation? As we observed 
back at the beginning of this installment, 
* ^modulation'' is a word with many 
meanings, and only a few of them are 
applicable to radio communications in gen- 
eral or to ham radio in particular. 



86 



73 MAGAZINE 





For radio usage, tiie word has been 
defined many times in many ways — and 
then applied with some new meaning which 
has made the older definitions obsolete. 

An example: In 1938, the Institute of 
Radio Engineers published an official defini- 
tion of "modulation" as being "the process 
of producing a wave some characteristic of 
which varies as a function of the instan- 
taneous value of another wave, called the 

wave." 

This definition was adequate until the rise 
of telemetry, in which the modulating signal 
is as likely to be a dc level as it is to be a 
"wave" (whatever a wave may be). When the 
modulating signal is a dc level, however, the 
1939 definition must be interpreted rather 
liberally to be appHed, 

Neither does it adequately cover the 
concept that what we call CW is actually 
ampUtude modulation (see last month's 
installment for a discussion of this 
idea) — and when RTTY is involved, it gets 
downright difficult to visualize the FSK 
signal as being the product of a "modulating 
wave"; the definition had to change. 

Another definition of "modulation" is 
that given in the Radiotron Designer's Hand- 
book^ fourth edition, page 1401; "The 
process by which the amplitude, frequency, 
or phase of a carrier wave is modified in 
accordance with the characteristics of a 
signal" 

This one, too, is a bit short in view of 
modern practice. No SSB or other sup- 
pressed-carrier signal could satisfy it, but no 
one would deny that a SSB signal is modu- 
lated. Neither could any type of pulse 
modulation qualify as modulation, under 
this definition. 

Note that neither of these definitions 
dted as examples is completely wrong; the 
trouble is that they^re merely incom- 
plete — and being incomplete is an unfor- 
givable sin in a definition. 

What's needed is a definition broad 
enough to include not only the types of 
modulation used in communications today, 
but hopefully aH future types of modulation 
as welL WeVe had to generate our own to 
get one that broad, but we feel that it 
accomplishes the goal and define modula- 
tion in such terms that we can move on to 



more specific details. 

Modulation, as we use the word in this 
installment at any rate, is the transmission of 
information by variation of some charac- 
teristic of a transmissible signal (which we 
will call the carrier) in such a manner that 
the original information (modulating signal) 
may be recovered from the result (modu- 
lated signal) by a definable process without 
prior knowledge of the original information. 

This does not require that the carrier be 
transmitted as a part of the modulated 
signal; elimination of the carrier itself may 
be one of the variations used to accomplish 
modulation. Just so long as information is 
transmitted in a manner which permits its 
recovery, that's modulation. 

Note that this definition is so broad that 
a conventional land-line telephone circuit or 
intercom qualifies as a "modulation" 
system* The sound waves which are the 
original information vary the current flow in 
the connecting wires; if we consider the 
at-rest current as "the carrier," then the 
change in current flow when sound strikes 
the microphone provides "modulation," and 
when the earphone or speaker changes this 
current flow back to sound waves, that's the 
**definable process" which demodulates the 
signal. It's hard to get much broader than 
that while remaining specific enought to be 
useful 

In practice, though, we don't deal very 
much with intercoms or land-lines, We*re 
radio operators, and we deal primarily in 
radio signals. Our "carrier" signals, then, will 
most often be radio waves. 

Our definition of modulation permits us 
to vary any characteristic of our carrier in 
order to apply the modulation. Let's see 
what characteristics of a radio signal we can 
vary in order to modulate that signal. 

What Can We Do To A Signal To Modu- 
late It? We've agreed that our carrier signals 
are^ most often, radio waves, and our defini- 
tion of modulation permits us to vary any 
characteristic of the carrier to apply modula- 
tion just so long as we can recover the 
original information from the modulated 
signal by some definable process. 

So the first step in deciding what charac- 
teristics of a radio signal we can vary to 
apply modulation is to decide just what 




1 



OCTOBER 1969 



87 



characteristics a carrier has in the fust place. 

A conventional ./ carrier is a single 
frequency radio wave; some attempts have 
been made to apply modulation to non- 
coherent or "noise" earners, but that's far 
from general practice (and no one has 
publicly reported any success in these 
attempts so far as we have been able to 
learn). Such a single- frequency if wave has 
three major characteristics: amplitude, or its 
strength relative to some scale of measure- 
ment; frequency, or its timing relative to 
itself i and phase, or its timing relative to an 
arbitrary starting time. 

In addition to the three m^or charac- 
teristics of ampEtude, frequency, and phase, 
there's an even more fundamental charac- 
teristic of its existence at all. If the wave 
does not have the characteristic of "exist- 
ence," it has no other characteristics at all. 
This might appear to be a merely philo 
sophical point — and at this level of 
examination it is. But if we accept "exist- 
ence" as a characteristic, we can then extend 
this idea to accept a **pattern of existence" 
as a special form of the "existence" charac- 
teristic; and this opens the door to the 
exotic forms of pulse modulation which 
convey information, not by the frequency or 
ampUtude of the carrier involved, but by the 
patterns in which the carrier either exists or 
fails to exist. 

We won*t labor this point very much, 
because pulse modulation is illegal on the 
most popular amateur bands, and we have 
more than enough to attempt to cover 
without getting into pulse work too deeply. 
We must, however, note it in passing in order 
to be complete. 

The three m^or characteristics which are 
varied in the most popular types of modula- 
tion are illustrated in Fig. 1 . 

When we vary any one of these charac- 
teristics to modulate our carrier, the re- 
sulting signal is identified according to the 
characteristic which we vary. If we vary the 
amplitude, we produce amplitude modula- 
tion or AM. Both SSB and DSB are special 
cases of AM, in which amplitude is varied 
but in addition the carrier itself (and in SSB, 
one sideband as well) is suppressed from the 
final modulated signal. If we vary the fre- 
quency, we have frequency modulation or 



AMPtiTUDE 




(FREOUENCY) pHASE 



Fig. t. The three characterUtics of an ac 
slne-wave signal which may be varied to 
produce modulation are shown here. AmpH- 
tude refers to the peak -to peak strength of 
the signal and may be measured in either 
volts or as current, so long as all references 
are consistent. Period is the time between 
two points of similarity in the waveform, 
such as the two zero-crossings shown; fre- 
quency is the reciprocal of period and is 
simply the number of cycles per unit of 
time. Phase is the timing between the signal 
itself and some arbitrary reference of tdenti- 
cdl period or frequency. 

FM. And if we vary the phase, we have phase 
modulation or PM. 

Fig* 2 shows a theoretical circuit which 
can be used to illustrate the differences 
between AM, FM, and FM, This circuit 
consists of an ac alternator driven by a dc 
motor, together with separate controls for 
the power appUed to the dc motor and to 
the alternator's field coils (the power level in 
the field coil of an alternator or a generator 
controls the power level produced by the 
device). 



DC 
1*1 PUT 




AC OUTPUT 



ALTERNATOR 



DC MOTOR 



Fig, 2. Th?s motor*alternator circuit illus- 
trates the differences between the major 
types of modusltion; it wouldn't work in 
practice because of the inertia of the moving 
parts, but it gives an idea of the principles 
involved* 

Before we use this circuit to illustrate the 
three major types of modulation, let*s brush 
up rapidly on some of the most basic facts 
of ac power generation by means of alteraar 
tors* After all, it's not one of the things we 
usually concentrate upon as hams. 

The major difference between an alter- 
nator and a generator is that an alternator 



88 



73 MAGAZINE 





produces ac while a generator puts out dc. 
This difference is accomplished by the 
absence of either a commutator or brushes 
in an alternator. Instead, the output is taken 
off directly through slip rings. (In practice, 
the "field** of an alternator is usually the 
rotating part, while the ^'armature" is 
stationary; this is done because a small 
amount of field power suffices to permit a 
large amount of armature power to be 
generated, and the d^gners want to mini- 
mize the amount of current which must pass 
through the slip rings.) 

Hie output power level, as we mentioned 
a few paragraphs back, is controlled by the 
amount of power applied to the field 
winding of either an alternator or a gen- 
erator. 

TTie output frequency of a generator is 
always dc, but ^the ac produced by an 
alternator most have some frequency. The 
altemator's output is virtually always pure 
sine-wave in form, and the frequency is 
determined by the speed of rotation of the 
alternator's shaft. The faster the rotation^ 
the higher the frequency produced. 

Now let^s look at the arrangement shown 
in Fig. 2y and imagine that the whole 
rotating system is so light and has so little 
inertia that we can change its speed of 
rotation almost instantly. For a start, 
though, let's adjust both Rl and R2 to their 
midpoints and take a look at the ac output 
With both Rl and R2 steady, the power 
level and the frequency of the output will 
remain constant, and the signal will look Hke 
that shown in Fig. 3. 



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Fig. 3. If both power controls in the circuit 
of Fig* 2 are left in mid-positron, the 
alternator's output will be constant in both 
frequency and amplitude, and will in conse- 
quence be a sine-wave sional such as that 
shown here. This corresponds to an unmod- 
uaited carrier stgnatp 

Now lefs vary Rl from minimuin to 
maximum and back regularly, thus varying 
the amount of power applied to the field 
coils of the alternator and in turn varying 




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the output power level, but leave R2 set at 
midpoint so that the signal is still of con- 
stant frequency; 




F!g, 4, If the speed control is left atone but 
the figid power control is varied regijlarlv 
from minimum to maximum and back 
again, the output of the alternator wift be 
almost zero when field power is minimum 
and will increase as field power Increases 
untti it reaches a maximum, then fall back 
as field power is decreased. The resulting 
waveform looks like this, and corresponds 
to amplitude modulation of a constant-fre- 
quency carrier signal. 

The result looks like Fig, 4, The period 
(which determines frequency) and the phase 
remain the same as in Fig. 3, but the 
amplitude varies from near zero to maxi- 
mimi and back down again as the field^coil 
power varies. This is amplitude modulation. 

For the next illustration, we'll leave Rl 
set at midpoint so that output power level is 
constant, but vary R2 at the same rate as we 
did Rl before. Assuming that the do driving 
motor can change speed instantly as we 
change the amount of power supplied to it, 




F»g. 5, When field power level is left con- 
stant, but the driving speed is varied from 
high to low and back, the alternator's 
output win be of constant amplitude but 
will vary in frequencv. This is shown in this 
waveform; the tick marks on the time axis 
are the times at which the waveform of Fig, 
3 crosses the axis, assuming that the left- 
most zero-crossing occurs at the same time 
for boht waveforms. This corresponds to 
FM. All of these waveforms have been 
traced from an X-Y plot produced by an 
electronic computer, using a carrier fre- 
quency three times that of the modulating 
signal in order to clearly show the actions. 
Normal practice is to use a carrier of several 
hundred to several million times the fre- 
quency of the modulating signal. 



and that the rotating system has so little 
inertia that it also can change speed 
instantly, our output signal in this case will 
resemble Fig, 5. 

The amplitude is constant, but the period 
and the phase both vary as R2 is varied. The 
tick marks on 'the baseline in Fig. 5 show 
where the waveform of Fig. 3 crosses the 
zero axis. You can see that as the dc motor 
turns faster and frequency rises, the period 
of the output signal shortens, and as it turns 




AC OUTPUT 



ALTERNATOR 




Fig. 6. If the circuit of Fig. 2 Is connected 
to a constant*frequency generator as shown 
here, frequency of the output signal will be 
locked to that of the second oenerator. 
Varying speed of the alternator now cannot 
produce permanent change in frequency^ 
but will produce change in phase of output 
signal while speed Is changing. Result corres- 
ponds to PM, and has same waveform as FM 
shown In Fig. 5; differences between FM 
and PM are largely a matter of definitions. 

slower, the period lengthens again. This is 
frequency modulation. 

We could perform the same actions again 
as we did to produce Fig. 5, but connect the 
output to a fixed-frequency generator 
through large series inductances as shown in 
Fig. 6. When we do this, the frequency is 
locked to that of the fixed-frequency gen- 
erator — but the phase will vary while the dc 
motor's speed is changing. This is phase 
modulation. We don't show a separate illus- 
tration of it, because for any single-fre- 
quency modulating signal, there is essentially 
no way to tell the difference between FM 
and PM at the output signal The outputs of 
each are identical. 

The functional difference between FM 
and PM lies in the fact that the amount of 
change in period or phase which occurs in 
the modulated signal is determined by 
different factors. When FM is employed, the 
amount of change is determined by both the 
strength of the modulating signal, and by its 
frequency. Lower-frequency modulating 



90 



73 MAGAZINE 



signals give greater change for the same level 
than do higher-frequency signals. When PM 
is employed^ the amount of change depends 
only upon the strength of the modulating 
signal. 

There is no practical difference between 
the two types of modulation, since any 
filtering of the modulating signal ahead of 
the point at which modulation occurs can 
compensate for the functional difference 
between FM and PM, and permit an FM-type 
output signal to be produced by a PM 
modulator, or a PM output signal to be 
produced by an FM modulator. Most com- 
mercial FM broadcasting uses an output 
signal which is about halfway between true 
FM and true PM characteristics. Almost all 
commercial two-way FM equipment actually 
uses phase modulation, in order to permit 
crystal control of center frequency. 

How Can We Modulate A Signal? Now 
that we have an idea of the basic charac- 
teristics and differences, if any, between the 
three major types of modulation — AM, FM, 
and PM — we need to know how we can 
modulate a signal with any of these types. 
The circuit of Fig. 2 is obviously not very 
practical for use at radio frequencies; we 
need something with a lot less inertia than a 
physical generator, and we must be able to 
control it with an audio- frequency speech 



Let's see just what we have to work with, 
and go from there. If we're going to modu- 
late a radio signal, we have some type of rf 
carrier generated by an oscillator and 
brought up to the output power level we 
desire by a series of r/ power amplifiers, and 
we have some sort of modulating signal 
which (except for TV) is an af signal. 
' To modulate that carrier, we must change 
its amplitude if we want AM^ its frequency if 
we want FM, or its phase if we want PM, 
Whichever of these characteristics we 
change, the change must be controlled by 
the af modulating signal. 

We can vary the amplitude of the signal in 
either of two basic ways. We can vary the 
amount of power supplied to one of the rf 
power amplifier stages, or we can vary the 
operating efficiency of one of those ampli- 
fiers. This can be done at any amplifier 
stage, but if modulation is appUed to any 



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OCTOBER 1969 



91 




amplifier stage except the one finally feeding 
the antenna, then special care must be used 

to keep later amplifiers from distorting the 
modulated signal — that is, all amplifier 
stages following the modulated one must be 
linear. 

We can vary the frequency of the signal 
by changing the operating conditions of the 
oscillator which originally generates the 
carrier. 

Phase of the signal can be varied by 
change of operating conditions in any of the 
rf amplifier stages, or by special processing 
very similar to the "phasing" techniques 
used to produce SSB. 

This all sounds simple enough, but for 
each of the three basic types of modulation 
an almost uncountable number of different 
ways of doing the job has been developed . 
To take AM as a partial example, we can 
apply the modulating signal to the plate, the 
screen, the control grid, or the cathode of 
the rf amplifier. If we apply it to the plate, 
we may connect it by means of a trans- 
former, an autotransformer, or a choke. We 
may also combine any of these connections. 
And each of these variations of AM has its 
own name, and its own set of rules for 
achieving the desired results. 

Before we explore any of the more 
specific details of the different techniques of 
achieving AM, let*s look at some points 
which all of them share in common* 

To do so, we*ll take two sine- wave signals; 
their waveforms are shown on the top two 
lines of Fig. 7. We're using a 3-to-l fre- 
quency ratio for these signals to make the 
illustrations easier to draw; in practice, the 
higher-frequency signal normally is several 
thousand to several million times the fre- 
quency of the lower. 

If we apply either of these signals by 
itself to the input of an amplifier, we will get 
approximately the same waveform at the 
amplifier's output - 

If we apply both at the same time to the 
input of an amplifier which is reasonably 
free of distortion, the output will look 
something Uke the waveform shown on the 
third line. The highei^lrequency signal **rides 
upon*' the lower, but except for that there's 
no interaction between the two. 

But if the lower-frequency signal is 




e 




Fig, 7, These waveforms illustrate modylat- 
or action. Top line (A) is carrier signat and 
b«low That (B) is the positive half-cycle of 
the modulating signal. If both are applied to 
a linear amplifier, output waveform win be 
that shown at C; carrier swings about the 
low%r-frequency waveform (dotted) rather 
than around the zero axis. Moduia tor's 
action is different (D); both signals swing 
around ^aro axis, but amplitude of carrier is 
controlled by amplitude of modulating sig- 
nal. Object of AM modulation circuits is to 
achieve waveform shown at D. 

applied to the ampMfier in any manner 
which causes the gain of the amplifier to 
change as a function of that signal, and the 
higher-frequency one is appUed to the input, 
then the output signal will resemble the 
waveform shown on the bottom Une. 

As you can see one of the major differ- 
ences between the lower two waveforms lies 
in the "zero reference" of the high-fre- 
quency signal. In the bottom waveform, 
both the low and the high frequency signals 
are symmetrical about the actual zero line, 
but in the next-to-bottom waveform, the 
"zero reference" of the high-frequency 
signal actually is the waveform of the low- 
frequency one, shown by the dotted line* 

A linear amplifier works to produce the 
effect shown on the next-to-bottom wave- 
form; a modulator produces the bottom 
waveform. 

Note that the requirement for producing 
the modulator-output waveform was that 
the lower- frequency signal — which repre^ 
sents the modxilating signal - had to rause 



92 



73 MAGAZINE 




the gain of the amplifier to change, while the 
higher- frequency signal - the carrier — was 
fed through from input to output in a 
normal manner. 

One of the simplest ways to change the 
gain of any amplifier is to change its grid 
bias. This -means that we should be able to 
feed the carrier to the amplifier grid as an 
input, and the modulating signal to the grid 
at the same time to vary the bias, and obtain 
modulating action. And, as a matter of fact, 
we can. 

Grid-bias modulation, as such a technique 
for producing AM is called, has a number of 
characteristics which make it preferable to 
any other for some types of signals, as well 
as other characteristics which make it unat- 
tractive for general use. 

Among its advantageous features is the 
fact that comparatively little power is re- 
quired in the modulating signal; all that's 
necessary is a voltage swing great enough to 
produce the desired change of bias. Another 
advantage is that this technique is capable of 
handling a wide frequency range in the 
modulating signal, since no transformers are 
necessary. This feature alone makes it almost 
the only way to apply a video-frequency 
modulating signal to a carrier, and grid-bias 
modulation is the standard technique in TV 
transmission. 

The same advantage is put to use in many 
receiver designs; any time a receiver uses a 
conventional triode or pentode as its mixer 
stage, with "control-grid injection" of the 
local-oscillator signal, a grid-bias modulator 
is at work. 

The disadvantages which make grid-bias 
modulation unattractive for general AM use 
include its requirement for critical control of 
operating conditons. The variation of bias 
introduced by the modulating signal must 
change the gain in a more or less linear 
manner in order to satisfy the modulation 
requirement that the original modulating 
signal be recoverable by a definable process. 
Thai is, if the positive peak of the modu- 
lating signal increases gain by say 20%, then 
the negative peaks of the same amplitude 
must reduce gain by the same percentage. 
Otherwise the modulator's output will not 
be a true representation of the modulating 
signal, and any process for recovering the 




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I 
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OCTOBER 1969 



93 




information won't get back exactly the same 
signal we started with. In more conventional 
terms J the modulation wEl be distorted. 

Adding to the problems of the grid-bias 
modulator is the fact that the modulating 
signal swings both positive and negative from 
zero, while the bias on a conventional 
amplifier must remain negative at all times in 
order for the control grid to retain control 
of the ampHfier's action. We can take care of 
this by supplying a source of fijced bias, 
which offsets the zero reference of the 
modulating signal to some fixed negative 
voltage. Then the actual grid bias will swing 
from moderately negative to less negative 
when the modulating signal goes positive, 
and from moderately negative to more nega- 
tive when the modulating signal takes a 
negative swing. 

Since this fixed-bias source is electrically 
in series with the modulating signal^ it must 
have low internal resistance. In fact, it must 
effectively be a dead short to ac signals at 
the lowest frequency present in the modu- 
lating signal, Grid4eak bias is not suitable; in 
practice, it*s usually necessary to provide 
voltage regulation for the bias supply in 
order to keep the resistance low enough. 

Other disadvantages to grid-bias modu- 
lation are that the modulated amphfier must 
be adjusted to produce only one-quarter of 
its maximum rated output in the absence of 
modulation; this is necessary because at the 
modulation peaks, the power output must 
be four times that at no-modulation levels* 
The modulated amplifier's grid imposes a 
varying load on tiie modulating-signal 
source^ which can cause distortion of the 
modulating signal before it ever actually 
reaches the modulator, and the rf driver 
supplying the carrier to the modulator must 
be capable of supplying two to four times as 
much power as is normaliy used, again in 
order to supply the drive at the modulation 
peaks. 

If a tetrode or pentode tube is used as the 
modulated amplifier, the modulating signal 
can be applied to its screen grid rather than 
to the control grid. Action is much the same 
as in pid-bias modulation, but adjustment is 
not so critical. Regulation of screen voltage 
is more customary than is that of grid 
bias — and in addition it's possible to achieve 



satisfactory screen modulation without 
regulating the voltages. The tolerances in 
screen modulation are great enough that 
many operators consider this the simplest 
and least critical type of grid modulation. 

Advantages of screen modulation are cir- 
cuit simplicity and the need for only a little 
modulating power. 

Disadvantages are the need for more 
critical adjustment (as compared to high- 
level modulation which we*ll examine a httle 
later) and reduced output power capabilities. 

All forms of grid modulation — grid-bias 
or control-grid, screen, or suppressor — are 
ways of varying the amphtude of the output 
signal by changing the operating efficiency 
of the modulated amphfier. Because of this, 
all of them must operate at below-normal 
efficiency in the absence of modulation, to 

leave room for modulation peaks when a 
modulating signal is applied. Most such 
modulating schemes operate at about 25% 
efficiency when there's no modulating 
signal, and produce their maximum rated 
output only during the relatively infrequent 
positive peaks of modulation. 

It's possible to operate an amplifier at 
nearly its maximum rated output in the 
absence of modulating signal, and produce 
up to four times the maximum rated power 
during modulation peaks. We can do this 
simply because the modulation peaks are so 
infrequent that the amplifier components 
aren't damaged during the occasional over- 
loads. To do this, though, we must stay far 
enough below maximum rating in the no- 
modulation or at-rest condition to permit 
average modulation levels to stay inside 
maximum ratings, and we must achieve our 
modulation by varying the supply power to 
the modulated stage rather than by varying 
its efficiency* Such a modulation scheme is 
known as high-level modulation, and it's the 
most popular form of AM in communica- 
tions use. 

High-level modulation is also called plate 
modulation, since the power variations occur 
in the plate circuit — but if the modulated 
state uses a tetrode, beam-power, or pentode 
tube the power to the screen grid must be 
varied right along with that to the plate in 
order to make things work. 

This type of modulation requires that the 



94 



73 MAGAZINE 





modulating signal be provided at rather 
hefty power levels; the modulating signal 
must supply half as much power as does the 
dc supply during at-rest periods. That is, a 
kilowatt amplifier that is to be plate modu- 
lated requires a modulator capable of 
supplying 500 watts of audio, and a trans- 
mitter operating with 100 watts input (dc) 
requires 5 watts of audio from the modula- 
tor. 

The audio power, at audio frequency, is 
combined with the dc power and the result 
is applied to the modulated stage. One of the 
most popular techniques for doing this is 
known as "series" plate modulation and is 
shown in Fig. 8; the ac from the modulating 



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Fig. 8. Series plate modulator, version. most 

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For such a scheme to work, the modu- 
lated stage's output power level must be 
determined directly by its dc power input 
level; the amount of input signal fed into its 
grid circuit must not be able to affect power 
output. As it happens^ a Class C amplifier 
that is driven slightly harder than necessary 
to saturate it fulfills this requirement. This 
fact makes high-level series plate modulation 
exceptionally simple to adjust. 

It isn't necessary to connect the modu- 
lating signal in series with the dc power 
input as shown in Fig. 8. There's another 
way of doing it that gets by with a little less 
in the way of components, but is somewhat 
restricted in other areas. 

This alternate way is actually an older 
technique. Instead of connecting the modu- 
lating ac and the power supply's dc in series, 
we can connect them in paralleL We must 
place a choke in series with the dc power 
supply so that it won't short the ac signal to 
ground. The result looks like Fig. 9, and the 
technique is known as "Heising** modula- 
tion. 




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Fig. 9. Parallef connection of nnodulator and 
modulated stage is a[$o possible. The circuit 
Is known as "Heising" rnodulatfon and has 
many variants. It is especiaMy popular for 
low-power equipment since it avoids need 
for bulky moduiation transformers and is 
capable of excellent modulation quafity. 
Disadvantage is that modualtor must be able 
to dissipate power equal to that supplied to 
rf stage. 

Heising modulation can be looked at in 
either of two ways. We'll try both: To 
compare it to the picture of series plate 
modulation which we've just presented, in 
the absence of modulating signal the modu- 
lated stage gets fuU dc power from the 
power supply. When the modulating signal 



goes positive, it adds to the dc power and 
the series choke prevents it from affecting 
things on the supply side of the choke, but 
the modulated stage gets more dc than 
before* Similarly, when the modulating 
signal goes negative it subtracts from the 
power level on the modulated-stage side of 
the choke, and the choke prevents the 
supply from making the level up. Thus the 
effect on the modulated stage is the same as 
with series modulation. 

The other way of viewing Heising modu- 
lation is based on the behavior of vacuum 
tubes. Both the modulated stage and the 
amplifier producing the modulating signal 
are fed from the same power supply, 
through the same series choke. When no 
modulating signal is present, both tubes are 
furnished the same supply voltage and each 
draws the current determined by its own 
operating conditions. 

When the grid of the modulating tube 
goes less negative, that tube draws more 
current The additional current through the 
choke produces a voltage drop and reduces 
the voltage available for both tubes at the 
same time. This cuts down the power avail- 
able to the modulated stage and so reduces 
its output. When the grid of the modulating 
tube goes more negative, the tube draws less 
current The reduced current through the 
choke releases energy from the choke's 
magnetic field and raises the voltage avail- 
able for both tubes. The modulating tube 
has no use for the increased voltage, so the 
effect is to raise the power input to the 
modulated state, and thus uicrease output. 

This second viewpoint indicates that a 
large part of the action of Heising modula- 
tion could be accomplished by using a large 
resistor instead of the choke - and this can 
be done. In low-power equipment where 
both space and cost are important^ Heising 
modulation with resistor instead of choke 
can be used. The percentage of modulation 
obtained when this is done depends upon 
the ratio between the current drawn by the 
modulating tube and that drawn by the 
modulated tube. If the modulating tube 
draws less current, modulation percentage 
remains comparativeiy low. If the modu- 
lating tube draws more current than does the 
modulated stage, though, it's even possible 



96 



73 MAGAZINE 





to overmodulate. 

Some circuits used for screen modulation, 
incidentally, amount to the application of 
the Heising technique to just the screen of 
the modulated stage, A notable example is 
that known as "clamp-tube*' modulation, 
which uses the Heising technique with a 
resistor rather than a choke. 

Cathode modulation, which is sometimes 
employed, is a cross between grid and plate 
modulation, because in most amplifiers the 
cathode is common to both the grid and the 
plate circuits. It shares most of the disadvan- 
tages of grid modulation and achieves few of 
the advantages of plate modulation^ and so 
has not found its way into general use- 
Now that weVe looked at the various 
ways to produce AM by varying the ampli- 
tude characteristic of the carrier, let's turn 
our attention to FM and PM. Since the 
output signals produced by FM and PM are 
so sLmHai, we'll look at these types of 
modulation together. 

We produce FM by varying the frequency 
of the carrier, and PM by varying the phase- 
However it's not possible to change the 
frequency of a signal without at the same 
time changing its phase^ nor can we change 
the phase without an accompanying chan^ 
of frequency. This makes the difference 
between FM and PM largely a matter of 
definition; the distinction normaUy used is 
that FM can be applied only to the oscil- 
lator, while PM is applied to the signal once 
its center frequency has been firmly estab- 
lished. 

The frequency of any rf carrier is estab- 
lished by a resonant circuit of some sort in 
the oscillator. This resonant circuit may be 
electromechanical, such as a quartz crystal 
which uses mechanical resonance to produce 
an electrical signal, or it may be electronic, 
such as a normal Ic tuned circuit. To vary 
the frequency, we must vary some factor in 
this resonant circuit 

One of the most convenient ways, today, 
to produce FM is to make use of the 
voltage-variable capacitor — a semiconductor 
device which acts as a capacitor, but the 
capacitance of which varies with the applied 
voltage. If one of these is included in an Ic 
circuit to provide a part of the tuning 
capacitance, the modulating signal can be 



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applied to it to change the tuning of the 
circuit in accordance with the variations of 
the modulating signal. This changes the 
oscillator frequency and produces FM, 

The voltage-variable capacitor is a rela- 
tively recent device, however, and a more 
conventional method of producing FM 
makes use of a special vacuum-tube drcuit 
called a **reactance modulator" or "react- 
ance tube" to accomplish the same purpose. 



OOI 





I— I osc 



Fig. 10. Typical reactance— tube circuit ts 
shown here. See text for details of opera- 
tion. 

The reactance modulator circuity a typical 
version of which is shown in Fig. 10, 
depends upon the phase relationships 
between grid and plate voltages and currents 
in a vacuum tube. Under most operating 
conditions, the plate current of a vacuum 
tube is in phase with the grid voltage applied 
to that same tube, without regard to the 
phase of the plate voltage. 

This means that we can place such a tube 
in a circuit where ac voltage is present upon 
the plate, and tap off some of this ac plate 
voltage. If we then shift the phase of this 
tapped voltage by 90^ and feed it to the 
grid, the plate current wiQ be 90** out of 
phase with the plate voltage. 

Such a condition defines the presence of 
reactance in the circuit. If the current lags 
the voltage by 90°, the reactance is induc- 
tive, and if the current leads the voltage by 
90^, the reactance is capacitive. 

In Fig, 10, resistor Rl and capacitor CI 
perform the voltage tapping and phase shift- 
ing actions, and cause the reactance in the 
plate circuit to be indue tive. 

The amount of reactance present depends 
upon the ratio of plate voltage to plate 
current, and the plate current is determined 
by the tube's transconductance (which is, in 
turn, determined by its grid voltage). If we 
apply our modulating signal to the control 
id, through rf choke RFCl which keeps 



the tapped-off plate voltage out of any 
earlier stages in our modulating-signal chain^ 
we can make it control the plate current and 
thus change the amount of reactance present 
in the plate circuit. 

And that^s exactly what we do in the 
reactance modulator. The net effect is that 
we have a circuit which acts as either a 
voltage-variable inductor or a voltage^ 
variable capacitor (to make it act as a 
capacitive reactance rather than inductive, 
we simply interchange the positions of Rl 
and CI to shift the grid voltage phase 90^ in 
the other direction). The resulting device is 
then connected across the frequency-deter- 
mining tank circuit of the oscillator. When 
the reactance tube changes the reactance 
present in the tank circuit, the ckcuit is 
instantly tuned to some different fre- 
quency — and the exact frequency to which 
it is tuned is determined by the modulating 
signal applied to the reactance-tube input 
terminals* 

If we connect a reactance tube, or a 
voltage-variable capacitor, to the frequency- 
determining tuned circuit of an oscillator, 
we can produce FM. This is notj however, 
the only application of the reactance tube. If 
we want more frequency stability than we 
can get with an Ic oscillator, and use crystal 
control^ to generate the carrier, then we have 
to xise PM rather than FM — and the react- 
ance tube can give us that, as well. All that's 
necessary is to connect it across a tuned 
circuit in the rf amplifier chain between 
oscillator and antenna. Its reactance varia- 
tions will detune the circuit to which it is 
connected, and this will change the phase of 
the signal to produce PM. 

The reactance tube also finds application 
in some receiver circuits, to provide auto- 
matic frequency control; the combination of 
a reactance modulator and a self-excited 
oscillator is sometimes called a voltage-con- 
trolled oscillator or VCO, The VCO is the 
heart of the advanced receiver technique 
known as ^^synchronous detection" or "phase 
locked reception*'; it*s also a key element in 
a TV receiver where it helps keep the sweep 
signals synchronized with those of the 
transmitter. 

Use of voltage-controlled circuit react- 
ances such as the voltage-variable capacitor 



98 



73 MAGAZINE 



or the reactance tube isn't the only way to 
achieve either FM or PM, Any practical 
oscillator circuit is, potentially, a frequency 
modulator, because the frequency of the 
signal it produces is affected by any change 
in circuit voltages. This is why we must 
regulate the voltages applied to the oscillator 
in order to keep frequency stable. If we 
want FM, we can simply reverse things and 
apply any of the amplitude modulation 
techniques to the oscillator itself. This will 
cause frequency changes which are deter- 
mined by the modulating signaL The ampli- 
tude changes which result can be wiped out 
by overdriving the following amplifier stages, 
so that only FM comes out at the antenna- 
We can produce PM by doing the same thing 
to an early amplifier stage, but it's more 
critical. 

These aren't the only techniques of 
achieving FM or PM; in the broadcast 
industry a special type of tube is often used 
which produces PM almost automatically, 

and one of the most popular ways of 
achieving broadcast FM is that invented by 
Major Armstrong and known as the *' Arm- 
strong method." It's used sometimes by 
hams, too, who are set up for SSB AM 
modulation using the phasing technique and 
want to produce PM as welL However, this 
method is based largely upon mathematical 
relationships and a knowledge of it isn't 
required in the Extra Class study questions, 
so well bypass it for now. 

Neither will we examine the production 
of SSB, DSB, or any of the suppressed- 
carrier modulation techniques at this point, 
since they are sufficiently complex to 
warrant their own separate discussion in a 
future installment. 

Whai Are The Characteristics Of A Modu- 
lated Signal? WeVe seen that modulation 
itself consists of any process for varying the 
characteristics of a carrier signal to permit a 
modulating signal to be transmitted, and 
we've looked at both the characteristics of 
the carrier which we vary, and at a number 
of techniques for varying them. How about 
the characteristics of the modulated signal, 
which results from this process? 

Like the carrier, the modulated signal 
possesses three major characteristics — am- 
plitude, frequency (or period), and phase. 



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OCTOBER 1969 



99 



^ 



iMai 




Unlike the carrier, though, the modulated 
signal never consists of only a single fre- 
quency - and so its characteristics are 
notably different. The difference is» in fact, 
what carries the information! 

It's only logical to deduce from this that 
the modulated signal's chajacteristics should 
be strongly influenced by the type of modu- 
lation used, and they are. Because the type 
of modulation employed has such an effect 
upon the various characteristics of the 
modulated signal, we'll look at the charac- 
teristics as they appear with different types 
of modulation separately. 

Amplitude modulation is still the most 
widely used type, and in addition we've 
considered it first all the way through this 
installment, so we'll examine the charac- 
teristics of an AM signal first and then turn 
our attention to FM and FM. 

In our previous installment we examined 
the how and why of mixer action, and 
discovered that when two signals of different 
frequencies are mixed (as opposed to 
linearly amplified) the result is not two, but 
four frequencies* The two original fre- 
quencies are still present in the output, but 
together with them are one new frequency 
representing the difference between the two 
(and so known as the "difference" fre- 
quency) and another new frequency which is 
the sum of the original pair (called the 
''sum" frequency). 

The process of amplitude modulation is a 
mixing process; any circuit which is capable 
of modulating a carrier frequency is non* 
linear, and when two or more frequencies 
are applied to a non-linear circuit, mixing 
occurs. 

Thus when we apply our carrier to an 
amplifier stage, and apply our modulating 
signal to that stage also, the output of that 
stage must contain at least four frequencies 
rather than just two. If the modulating signal 
is anything more complex than a simple 
single sine-wave, as it usually is, there are 
many more than four frequencies present in 
the output. 

Since the modulator does its job by 
mixing, the output must contain signals at 

each of the original input frequencies, at 
their sum, and at their difference. 

Normally, though, a modulator is used to 



apply audio-frequency information to a 
radio-frequency carrier. In this case, the af 
modulating signal will be at a frequency so 
far below that of the carrier that no trace of 
the audio signal itself can appear in the 
amplifier's output circuit; it's rejected by the 
tuned circuits. 

The sum and difference frequencies, 
though, are extremely close in frequency to 
the carrier If we're modulating a l-mhz 
carrier with a lOOhz audio signal, then the 
difference frequency will be at 999.9 khz 
and the sum will be at 1000.1 khz. These are 
so close to the carrier that most tuned 
circuits which accept the carrier will also 
accept the sum and difference frequencies. 

Since these two new signals lie very close 
to, and on both sides of, the carrier, they are 
known as '*side frequencies." The name 
dates from the early days of radio, before it 
was generally realized that modulation and 
mixing were one and the same effect. 

When a band of many frequencies com- 
poses the modulating signal — the normal 
case with voice signals — then the sum and 
difference products alongside the carrier are 
no longer called "side frequencies"; instead, 
they are known as "side bands." Within the 
past several years, the two words have 
blended into one, and we know these parts 
of the modulated signal now simply as 
"sidebands." 

The lower sideband corresponds to the 
difference frequencies, and the upper side- 



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Fig, 11. Side frequencies are generated by 
mixing or modualtion whenever two input 
signals are so widely separated in the spec- 
trum as are af and rf, Differpnce signal is 
lower in frequency than carrier, and sum 
frequency is higher. When an audio band, 
rather than a single spot frequency, is 
applied to mixer or modualtor, output 
consists of carrier and two sidebands. Lower 
sideband (LSB) corresponds to difference 
frequencies, and upper sideband (USB) to 
sums. Total signal bandwidth extends frorn 
lowest frequency in lower sideband to high- 
est frequency in upper srdeband, or twice 
the highest frequency in the original audio 
band. 



100 



73 MAGAZINE 




>and to the sum frequencies, produced by 
nixing the carrier with each component of 
:he modulating signal. Fig, 11 shows a single 
pair of side frequencies (top) and a typical 
set of sidebands (bottom) as they might be 
/iewed on a wide-range spectrum analyzer- 

In passing, we noted in our previous 
instaOment that mixing action comes 
through a multiplication of one signal by the 
other If each of the signals applied to a 
modulator (the carrier and the modulating 
signal) are described by their equations, the 
result in each case is a mathematical expres- 
sion involving the sine of the amount of time 
since **zero time." If the two are multiplied, 
the trig relationships involved in multiplying 
one sine function by another produce an 
equation with one sine term and two cosine 
terms; the sine term turns out to represent 
the carrier, and the cosine terms represent 
the sum and the difference frequencies. All 
of this math was worked out in the mid- 
1920*s-but at the time the "side fre- 
quencies*' and resulting sidebands were 
thought to be a mathematical fiction. The 
experts felt that they couldn't possibly 
exist, but they were necessary to make the 
math work out properly. 

Then in 1927 John Carson demonstrated 
the physical existence of the sidebands^ and 
took out a patent on a system of single 
sideband transmission* The math was vindi- 
cated; unfortunately, it*s still not an 
accurate picture of what goes on, because 
the mathematical expression fails to account 
for the original modulating signal. 

Much later it was realized that modula- 
tion and mixing are two names for the same 
process (at least so far as AM is concerned), 
and the body of theory developed to 
describe mixer action was applied. Many 
college-level engineering texts still, however, 
teach modulation without going into its 

connection with mixing. 

The references generally available to most 

hams, though, are even less cle^, because 

many of them leave the impression that the 

amplitude of the carrier is varied to produce 

amplitude modulation. 

In fact, we've even implied as much 
ourselves — and its time to correct that idea. 

We saw just a few paragraphs back that 
the sidebands lie very close indeed to the 



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101 



carrier in the frequency spectram. For all 
practical purposes, the two sidebands and 
the carrier together constitute a single signal, 
because most receivers are not sufficiently 
selective to strip out any part of this 
combination from the rest of it. 

But when this composite signal is applied 
to any electronic circuit, there's only so 
much energy present in that circuit at any 
specific instant. That is, the energy present 
in the circuit is the net total of that 
contributed by the lower sideband, the 
carrier, and the upper sideband , all at the 
same time. If the energy in the sidebands is 
of just the right amount and polarity to 
completely cancel the energy of the carrier, 
this net total will be zero, and on the other 
hand if the same amount is contributed but 
with polarity to boost rather than buck the 
carrier level, the total will be twice as much 
energy or four timw as much power as with 
the carrier alone. 

The variations of net energy in the total 
signal produced by the amplitude and 
polarity changes of the sidebands relative to 
the carrier are called the *" modulation 
envelope^' or simply the "envelope" of the 
signal — and in amplitude modulation it*s 
the amplitude of the envelope rather than 
that of the carrier which varies. 

The distinction is more theoretical than 
practical, because as we said, it's almost 
impossible to separate parts of the com- 
posite out with most receivers, A "selectable 
sideband" receiver, though, has the ability to 
accept or reject a single sideband of an AM 
signal, and the whole art of SSB is based on 
the fact that all the modulation information 
is contained in the sidebands, and that the 
sidebands are mirror images of each other so 
that only one is necessary to carry all the 
information. 

Fig, 12 shows the envelope of an AM 
signal over a half-cycle of modulating signal* 
This is not typical since only a 3-to-l ratio 
between carrier and modulating frequencies 
was used J in order to permit easy vision of 
the relationships between net energy in the 
composite signal (dotted Une) and the 
envelope (sohd). Normally the frequency 
ratio is much higher. Like all the other 
waveform illustrations in this installment, 
this figure was traced from a plot produced 




Fig, 12, Envelope of AM corresponds to the 
peaks of the energy levels present in the 
connbined carrier and both sidebands (dot- 
ted waveform). This iUustration shows a full 
cycle of modulating signal from negative 
peak to the next negative peak^ with six 
cycles of carrier/sideband. 



by an electronic computer. i 

The relationship in strength between 
either sideband and the carrier is a measure 
of an AM modulation system's effectiveness. 
The stronger the sideband, as compared to 
the carrier, the more effective the system. 

This relationship is usually expressed by 
engineers as the "modulation index" of the 
modulated signal, but hams and the FCC 
refer to it in a slightly different form caUed 
the "percentage of modulation/' This^ again, 
is a carryover from the days when only the 
envelope was considered - and as a result 
the definitions of modulation percentage 
make very little sense when applied to a 
suppressed-carrier signal, and none at all 
when applied to FM or PM. 

For "percentage of modulation" is deter- 
mined by the ratio of peak envelope voltage 
(or current) to the carrier voltage (or cur- 
rent) without modulation. Fig, 12 shows 
these parts of the envelope. The carrier level 
is indicated by the dotted line. 

Percentage of modulation may be dif- 
ferent for "upward modulation," which is 
the half-cycle of the modulating signal which 
produces the positive modulation peak, than 
for "downward modulation" which pro- 
duces the negative modulation peak. For 
sine- wave modulation both are the same, but 
for voice the two are normally different The 
larger of the two figures is customarily used 
as the modulation percentage of the signal. 

In the case of upward modulation, the 
modulation percentage is 100 times the ratio 
of the positive modulation peak (above 
carrier level, as shown) to the carrier level. In 
Fig. 12, both are equal and the ratio is 1/1, 
so the modulation percentage upward is 
100%, 



102 



73 MAGAZINE 



CAf?RiER 
LEVEL 




F1g> 13. Key factors invofvad In calculdtlng 
percentage of modulation are identified 
here. Wave form repre^nts tOO% modulated 
enverope (carrier cycles are not shown) as 
described in text. Carrier level furnishes zero 
reference for envelope; envelope's outline 
dupficates modulating signal on both edges* 

For downward modulation, the per- 
centage is 100 times the ratio of the negative 
modulation peak (below carrier level) to the 
carrier level. In Fig. 12, again both are equal 
so the ratio is 1/1, making the percentage 
again equal to 1 00%, 

FCC regulations limit modulation per- 
centage of an AM signal to 100% in either 
direction. There's very good reason for this 
in the downward direction; 100% modu* 
lation justs cuts off the envelope at zero 
energy. Anything in excess of 100% modu- 
lation represents an effort to make the 
envelope less than zero; it doesn't work. 
What happens is that the negative modula- 
tion peaks are highly distorted, and this 
distortion produces spurious signals which 
clobber communications over a wide spread 
of the frequency spectrum. See Fig. 13. 

Modulation percentage is relatively inap- 
plicable to SSB or DSB, since these signals 
have no '"carrier level'' to m^isure against 
We'll find out why it*s not applicable at all 
to FM or PM a little later. 

When you understand how modulation 
percentage is defined, it*s not too difficult to 
visualize the envelope of a sine-wave-modu- 
lated signal at any prescribed percentage of 
modulation. Simply establish a carrier with a 
peak voltage of, say» 10, and then sketch in 
the modiilating sine-wave along the carrier 
level Positive peaks of the modulation 
envelope will rise above carrier level by the 
modulation percentage times the carrier 
level; that is, with a 10-volt carrier and 50% 
modulation, positive peaks wiU rise to IS 
volts. Negative peaks will drop below carrier 



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level by the same amount; m our example, 
to 10-5 or 5 volts. 

If the percentage exceeds 100%, positive 
peaks still go up in the same way, but 
negative peaks cut off at the carrier zero 
reference line to produce a distorted 
envelope. 

We have seen how all of the information 
content of the envelope is produced by the 
sidebands, in AM, We have also seen how the 
sideband energy levels produce the envelope 
of the signal. It shouldn't be too surprising 
to learn that all of the power furnished by 
the modulating signal goes into the side- 
bands. 

Strictly speaking, that's true only of plate 
modulation, because that's the only type of 
modulation we\e examined in which the 
input powef is varied to produce modula- 
tion. But with plate modulation, that is what 
happens. The amplifier treats the carrier the 

same at all times, whether modulation is 
present or absent When modulation is 
applied, the modulating-signal power pro- 
duces the sidebands. 

We adso saw that 100% modulation is 
produced when the sidebands have just the 
right amount of energy to completely cancel 
out the carrier energy at the negative modu- 
lation peaks. Because of some rather com- 
plicated phase relationships^ this occurs 
when each of the two sidebands has pe^ 
voltage equal to half that of the carrier. 
Then tiie two sidebands each contribute 
half, and the total exactly balances out the 
canier. 

With half the voltage in each sideband, 
tlm means that each sideband must contain 
1/4 as much average power as does the 
carrier m order to attain 100% modulation 
with a sine-wave signal. To put 1/4-carrier- 
power levels into each of two sidebands 
requires that the modulator supply pow^ 
equal to half that in the carrier. 

Should we reduce the modulation per- 
centage, the amount of power required in 
the sidebands would also be reduced. Should 
we use something other than a sine wave as a 
modulating signal, as for example normal 
speech, we could also get by with less power. 
As a rule of thumb, though^ most designers 
try to furnish half as much audio power as 
there is gQing to be rf power in the carrier. 



This offers a safety margin, and also permits 
speech processing such as clipping and com- 
pression without running short of modu- 
lating power. 

Because the carrier level remains constant 
with plate modulation, which is the most 
popular kind, many people believe that 
carrier level is always constant with modula- 
tion. This is not necessarily so. 

When AM is achieved by varying effi- 
ciency of an amplifier, as is done in all types 
of grid modulation, it's simply the designer's 
choice as to whether carrier remains con- 
stant, or varies with modulation. Many 
designers of such systems have attempted to 
produce output indistinguishable from that 
produced by plate modulation — and in 
these systems, carrier remains constant. 

Other designers, though, have chosen to 
control the carrier level AH controUed- 
carrier systems (a notable example is a 
Heathkit design originally introduced about 
1955 and still cuiient) produce carrier levels 
which vary with the intensity of the modu- 
lating signal. 

Even in these, though, the ratio of power 
between carrier and sidebands remains fixed 
by the modulation percentage. 

Now that weVe given AM signal charac- 
teristics a thorough going-over, let*s see how 
FM and PM differ 

For a starter, the envelope of an FM 
signal carries no information. In fact, a legal 
FM or PM signal has no envelope variations 
at all, because that would constitute AM and 
the rules don*t permit mixing the types. 

FM and PM signals do, however, have 

m 

si#bftn4s — many more sidebands than are 
pro4uced by AM at the same modulation 
index. Moft texts drop into a deep and 
somewhat muiky study of Bessel functions 
when they attempt to discuss the distribu- 
tion of $ideb»nds in FM signals. Since we 
don't, at this point, need all that infoi^ 
mation, let's 9kip the details of how they are 
produced and simply note that the visualiza- 
tion most of us cany of an FM signal - a 
aingile carrier which wande^^ about in Ire* 

qu^liqy around a "center*' frequency, and 
whose wan4«ruigs carry the modulating 
signal information - is np more accurate in 
detail than 19 the conventional view of an 
AM signal as one whose strength varies with 



104 



73 MAGAZINE 




modulation. See Fig. 14. 

In both cases, it's the envelope charac- 
teristics which vary rather than those of any 
specific components within the signal. 

This comes about because a signal of any 
one frequency cannot be at any other 
frequency — and it can't get from one fre- 
quency to another without getting to one in 
between first. When it*s necessary to analyze 
in detail how a modulation system works, 
it*s more convenient to view the si^al as 
being made up of many signals each of 
specific frequency and strength^ which are 
either present or absent^ than it is to try to 
consider one signal of varying frequency or 
strength. 

Since the advent of SSB^ it's become 
necessary to examine AM in this amount of 
detail. When looking at FM, we can get by 
with studying only the behavior of the 
envelope; we don't have to break down the 
various components within the envelope. 

The FM signal is characterized by its 
center frequency, strength, and the amount 
of deviation above and below this center 
frequency. The deviation may be expressed 
either as an absolute frequency difference in 
hertz or khz, in which case it's called 
"swing/' or as the "deviation ratio," which 
is the ratio of the maximum carrier-fre- 
quency deviation to the highest nlodulating 
frequency. The effectiveness of the modula- 
tion is measured by the *' modulation index," 
which is the ratio of the carrier frequency 
deviation to the modulating frequency. That 
is, a 3-kliz swing* with a l-khz modulating 
frequency would produce a modulation 
index of 3; the same swing with a 6-khz 
modulating frequency would produce a 
modulation index of O.S, and if the 34c hz 
swing were the maximum employed in the 
system, and the 64:hz signal the highest 
frequency^ then the deviation ratio would 
also be 0.5. 

In ham use below 52,5 mhz, the maxi- 
mum bandwidth which an FM signal is 
permitted is 6 khz (the same as a state-of- 
the-art AM signal). If frequency response is 
limited to 3 khz, then the deviation ratio 
would be 2; the modulation index would 
vary with the modulating frequency, from 2 
at the high-frequency limit up to 20 at a 
300-hz modulating signal 




Fi(|. 14. This composite view shows an FM 
signal's waveform (solid line), compared to 
that of an unmodulated carrier of the same 
center frequency {dotted} and to the modu- 
lating sine- wave (also dotted)^ Sine-wave 
shape of carrier and modulated-signat wave- 
forms has bean simplified to straight line 
connecting peaks and passing through a^is 
at proper zero-crossing time. 

In AM, modulation index is the ratio of 
modulation peak level to average carrier 
level — the same quantity which we multiply 
by 100 to obtain modulation percentage. A 
100% modulated AM signal has a modula- 
tion index of 1,0, Modulation percentage is 
sometimes defined^ in fact, as 100 times the 
modulation index. 

This is part of why modulation per- 
centage has no meaning in FM work. Modu- 
lation peaks are always at the same level as 
the average carrier level, and by conventional 
definitions aU FM has 0% modulation. But if 
100 times modulation index is used, then 
the modulation percentage of a legal ham 
FM signal may vary from 200 up to 2000%, 
depending upon modulation frequencies 
present 

In practice^ the deviation ratio is used to 
measure FM in the same way modulation 
p^centage is used for AM. 

But while it*s possible, physically, to 
overmodulate an AM signal and produce 
splatter, this cannot be done with FM. An 
FM signal with more swing than a receiver is 
designed to accomodate will sound distorted 
on that receiver - but will be fine on any 
receiver which can handle the maximum 
swing of the signal. The limits on swing of an 
FM signal are administrative, while those 
upon modulation percentage of AM are 
physical. ... 73 Staff 



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OCTOBER 1969 



105 




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73 MAGAZINE 



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Peterborough. N. H. 03458 



OCTOBER 1969 



107 



■^1^^ 



Ed Gribi VJB61ZF 
229 Vivian Street 
King City, CA 



Hi 



am 



Jamboree 



Editor Wayne waxed eloquently in July 
73 about the need for attracting newcomers 
into our hobby. One of the largest groups of 
ready*made potential newcomers are the ten 
million or so Boy Scouts around the world. 
There are a number of points of contact 
between scouting and amateur radio, but 
one of the best is the annual "Jamboree On 
The Air," 

What is Jamboree Or^The Air? Let me try 
to describe its background, purposes, and 
format for you from a very personal stand- 
point, I had the good fortune to be one of 
the operators at K7WSJ, the official amateur 
station at the World Scout Jamboree at 
Farragut State Park, Idaho, in August^ 1967, 
Those ten days were one of the high points 
of my 43 years. Meeting Lady Powell, the 
night the entire Australian contingent jam- 
mod our shack as we worked VK after VK 
(no third party traffic, please!); the colors of 
the tents and banners against the green 
Idaho forest; the Belgian Scout who brought 
his sleeping bag into the shack in the hope 
we could work an ON; the myriad of 
colorful uniforms and thousands of smiling 
faces thoroughly enjoying one of the great 
experiences of their Mves, These and hun- 
dreds of other thrills and pleasant memories 
will always be with me. 1 made many lasting 
friendships from a dozen different countries 
and still exchange letters with several of 
them. But I was one of the lucky ones. 
Fewer than 1% of the Scouts are able to 
attend a World Jamboree or one of the 
greatest national or regional jamborees. 
Therein hes the reason for the development 
of Jamboree On The Air, 







Scouts at Geneva, Switzerland, Operator is 
Len Jarrett, HB9AMS, Director of Adminis- 
tration, Boy Scouts World Bureau^ 

A number of Scouts operating the ama- 
teur station during the World Jamboree in 
England in 1957 were concerned that so few 
Scouts of the millions could actually partici- 
pate in the face to face building of interna- 
tional friendships. Perhaps radio could ex- 
tend the reach of the brotherhood and 
involve more Scouts, even if vicariously, in 
such events, Les Mitchell, G3BHK, con- 
ceived the idea of a Jamboree on the air and 
the first formal JOTA was in May^ 1958, 
The idea has mushroomed with the aid and 
abettment of enthusiastic Scouts, Scouters, 
and amateurs so that now thousands of 



108 



73 MAGAZINE 




stations from every Scouting country parti- 
cipate in the event every year. 

The primary purpose of J OTA, therefore, 
is to enable Scouts everywhere to talk to 
other Scouts across town or around the 
globe by radio, A secondary purpose is to 
give them exposure to amateur radio which 
may help a boy discover a latent career in 
electronics or some allied field , or perhaps in 
amateur radio as a hobby. It has undoubted- 
ly encouraged many a boy to work on 
related Scouting accomphshments such as 
radio and other merit badges. 

The 12th annual Jamboree On The Air 
will occur October 18 and 19, (GMT), 1969. 
Participating stations with Scouts and Scout- 
ers in their shacks will be calling **CQ 
Jamboree** on aU bands and modes during 
that period. There are no rules nor points to 
count "-tills is not a contest! The theme is to 
let Scouts talk to Scouts wherever they may 
be. There are no formal fixed frequencies, 
but the Boy Scouts World Bureau has 
recognized traditional operating practices by 
noting the following as ''World Scout Fre- 
quencies": 

3,590 khz. -CW 
3,740 khz, — European phone, 

U. S. Novice CW 
3,940 khz, - U, S. phone 
7,090 khz, — CW, European phone 

14,090 kliz, -- CW 

14,290 khz. — phone 

21,140 khz. - CW, U. S. Novice 

21,360 khz. - phone 

28,190 khz, - CW 

28,990 khz, -phone 
In addition, U. S. amateurs have found 7290 
khz to be a good frequency and 7190 khz a 
good CW frequency for novices. 

If you, as an amateur and/or Scout or 
Scouter are not already involved, then per- 
haps this should be your year for Boy 
Scouts, You might contact a local Scout 
office or executive or, even better, a Scout- 
master or Den Mother or Patrol Leader. 
They may not be familiar with the event 
unless they are avid readers of "Scouting," 
"Boys Life,*' or **World Scouting." You may 
have to explain the purposes and what they 
might reasonable expect from participation 
(remeniber, though, that propagation may 
not cooperate). In many areas amateurs talk 



to Scout Troops several weeks before the 
event to explain such things as how we're 
able to communicate hundreds or thousands 
of miles, typical terminology involving 
equipment and operatmg, and perhaps even 
to arrange a preliminary visit to a station. 

During the event get your amateur opera- 
ting exchanges out of the way as briefly as 
possible. Then turn the boys loose and let 

them talk to other Scouts. If they're a little 
totigue-tied at first, encourage them to talk 

about such things as themselves and their 
own personal involvement in Scouting; tlieir 
Patrol, Troop, Post, or Den; their camping 
and other activities; their home, town, area^ 
and its culture and environment; and, of 
course, to ask similar questions of those on 
the other end, DonH feel like you have to 
hurry off to make more contacts or to let 
them talk to some exotic DX Scout station. 
It is much more meaningful and closer to the 
purposes of the event to have a two-hour 
ragchew with a gang 100 miles away than it 
is to exchange signal reports with stations in 
ten countries. I've hstened in on some 
marvelous QSO's during past events where, 
for instance, a couple of Patrol Leaders in 
different parts of the USA exchanged notes 
on their summer camp experiences or Ten- 
derfeet talked about their first hike. On the 
other hand, if conditions are favorable it can 
be a real thrill for them to talk "live" to a 
Scout in some foreign country. The language 
barrier is no barrier when international 
friendsliip is involved. 

When it's all over the very least you'll 
have is a lot of satisfaction in having 
associated with a fine group of young men, I 
know it always restores my faith in the basic 
good sense of our youth whenever 1 get 
around a group of Scouts, Beyond that there 
are several things that can be done that will 
extend the interest period and firm up the 
relationships begun. Encourage the Scouts to 
make up and send QSL cards to the groups 
they talk to and perhaps to initiate corres- 
pondence or exchange of photos. Many 
permanent overseas links between Scouting 
groups have begun this way. And by ail 
means send a note regarding your JOTA 
activities (including contacts and critique) to 
your National Organizer (in the United 
States it's Harry Harchar W2GND, Boy 



I 



OCTOBER 1969 



109 





Scouts of America, New Brunswick, New 
Jersey- 08903) with a copy to the World 
Organizer^ Len Jarrett HB9AMS, Boy Scouts 
World Bureau, Case Postale 280, 1211 Gene- 
va 11, Switzerland, Len is an enthusiastic 
participant in JOTA's and will again this 

year be operating from 4UIITU until a 
permanent World Bureau station can be set 
up. World Scout Bureau will send you a 
handsome QSL-sized ceritficate of participa- 
tion in return for your courtesy in telling 
them of your own activities. 

So youVe done all these things but it stiU 
seems like the contact between amateur 
radio and Scouting- should be more than a 
once-a-yeai thing, I always have that feeling 
myself. There's no reason why you couldn't 
continue the relation with a particular 
Scouting group with such diverse projects as 

teaching them code, providing communica- 
tions at a Camporee or camp, or maintaining 
schedules with someone contacted during 
JOTA. There are several nets devoted to 
Scouting in various portions of the world, 
G3BHZ and HV3SJ operate on 14290 khz 
on Saturdays at 0930 GMT, mostly with 
other European participants. World Scout 
Net operates on 21360 khz at 1800 GMT on 
Saturdays. Bob Hallock WA7G00, is the 
prime mover in this group. Bob was an 
operator at K7WSJ in 1967 and at the 
National Jamboree station this last July, Bob 
is an Eagle Scout from Boise, Idaho, and has 
injected a lot of enthusiasm into the WSN. 
These gBOUps are devoted to the furtherance 
of the ideals of Scouting via amateur radio 
and as such deserve support and participa- 
tion by aH with similar aims. 

I have one suggestion regarding JOT A 





Australian Scouts 

1968 JOTA. 



at VK2BW during the 



At Baden Powell House, London— English 
Scout headquarters. 

Operation this year that I haven't even 
cleared with Len Jarrett at the World Bur- 
eau, Let*s try using these World Scout 
Frequencies as calling frequencies during 
JOTA instead of ragchew frequencies* In 
other words J call "CQ Jamboree" on the 
frequency, then QSY up or down for a QSO. 
That way there would be much more effi- 
cient utiltization of frequency space and 
much less random calling. Perhaps we could 
even have net control stations active on one 
or more of the frequencies, particularly 
21,360 khz. I imagine Bob WA7G00, could 
organize two or tliree net controls to pick up 
breaks, periodically call a list of stations and 
localities on the frequency, and help stations 
who wish to QSY for a chat. Til see if 
something 4ike this might be arranged by the 
time this appears in print. During other 
times these frequencies should make natural 
frequencies for any stations interested in 
Scouting to get together. 

So there you have the story of Jamboree 
On The Air* If youVe interested in young 
people and in the health of amateur radio, 
this should be a regular event for you. If you 
feel as I do that once a year just whets your 
appetite, then you might follow some of 
these other suggestions that could lead to a 
Jamboree On The Air tlie year round. 

r* x^ • . . WBoIZF 

Reference: 

"Scouting and the Radio Amateur/* QST, July, 
1967, p,52, WB6IZF 



110 



73 MAGAZINE 





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transceiver. Write to Varitronics^ 3835 North 
32nd Street, Suite 6, Phoenix, AZ 85018. 

More Power for FM'ers 

Varitronics Inc. has come out with two 
new linear amplifiers for users of their 
deluxe FDFM-2 transceiver. 

For the mobile enthusiasts, the com- 
pletely solid state FM-20M mobile rf linear 
amplifier can be had for $150.00, weighs but 
a pound, requires 12*5 vdc and can boost 
your nere 2 watts to 20 watts input and 10 
watts rf output. For those using the FDFM-2 
transceiver as a home station, you might 
look into the new FM-2OBM5 available for 
$235.00. It weighs 6V2 pounds, is completely 
solid state^ has a built-in ac power supply 



requiring 117 vac, and like the FM-20M 
mobile model, can increase 2 watts input to 
20. For further in forma tion, write Vari- 
tronics Inc., 3835 North 32nd Street, Suite 
6, Phoenix, Arizona 85018. 



,.+rtl^' '^ vr « i^-r 



r M ^ 4\wir - ^*_4r ^# ^ ^> ^ « 



A ^ 4 J .# 




Now the HA^SOO 

Lafayette introduces the new completely 
solid-state, model HA-800 six-band SSB/ 
AM/CW amateur receiver. This 80-6 meter 
amateur receiver has a built in dual solid 
state power supply permitting either 117 
volts ac or 12 volt dc operation with zener 
regulation. The receiver section sports 3 
FET's and 2 mechanical if filters to assure 
high selectivity with superior noise suppres- 
sion* An S meter, product detector and 
crystal calibrator (less crystal) are among the 
other features. Specifications: sensitivity: 
better than 1 uv on 80, 40, 20 meters, ,5 uv 
on 15, 10 meters and 2,5 uv on 6 meters; 
selectivity: -6db at ±2 khz, -60db at ±6 khz; 
intermediate frequencies! 1st if 2.608 mhz, 
2nd ?/ 455 khz; BFO frequency: 455 khz 
±2-5 khz; image rejection: better than -40db; 
audio output impedance: 50 ohms; power 
requirements 105-120 volts 50/50 hz ac, 12 
volts dc (negative ground); size: 15w x 9%d 
X 8!4h. For additional information, write 
Lafayette Radio Electronics Corp., Ill 
Jericho Turnpike, Syosset, L.L, NY 11791. 




FMT-1 FIVI Transceiver 

VHF Associates, Inc., is now offering a 
six channel, 5 watt input FM transceiver for 
$289.95, It operates with a dc input voltage 
of 1 2 to 15 volts and weighs but six pounds, 
being fully transistorized. ICs are used in 
the if and audio circuits for superior perfor- 





OCTOBER 1969 



111 



mance and reliability and the receiver is dual 
conversion. The transmitter has a 20 khz 
maximum deviation and has a frequency 
range of 142 to 149 mhz. For further 
information, write VHF Associates, Inc., PO 
Box 22135, Denver, CO 80222, 

Arcturus 

Arctunis Electronics Corp. has been lucky 
enough to acquire 9800 obsolete tubes, circa 
1925-1930, to add to their considerable in- 
ventory of the same hard-to-obtain types. 
Listings plus prices of thousands of other 
items are included in their recently published 
Mid- 1969 Catalog, which they will be glad to 
send to you without any obligation on your 
part. Write direct to Arcturus, 505-22nd St., 
Union City, N J. 07087. 





Cassette Albums Available 

Now that more and more of us are using 
cassette tape recorders to tape our friends 
and unusual DX contacts, the problem of 
storing those little cartridges begins to in- 
trude. They are a terrible size to store and 
they soon rattle around in the desk drawer. 
Robins Industries, College Point, N.Y. 
11356, has come out with a nice album. 
Each cover holds six cassettes and each 
compartment has a built-in stop to keep the 
tape from going slack! The cost is $3.30 
each. A bargainl 

Microf lect Towers 

Aluminum towers may be harder to 
manufacture, but they sure have a lot of 
advantages for the fellow who has to put 



them up and use them. 

First of all, of course, they weigh but a 
fraction of what we are used to with steel 
towers . . . about one third as much, A ten 
foot section weighs only 12y2 pounds! This 
may not mean a whole lot to you when you 
are dawking it around on the ground, but 
when you are putting the sections one on 
top of the other up in the air you will bless 
every last pound that you don't have to 
struggle into place. 

The weiglit makes an enormous dif- 
ference if you have your tower hinged at the 
bottom for easy work on the beam and 
rotator. It's the difference between walking 
a 72 pound, sixty foot tower into place and 
walking a 212 pound monster into place. 
One man vs, maybe three to do the job. 

Some towers are just terrible for climb- 
ing. Those diagonal struts hurt the feet and 
are dangerous if at all damp. The Micro fleet 
tower is different. Some genius thought 
ahead a little bit and decided that it would 
be a good idea to build flat step segments 
into each brace. The result is a tower that 
you can walk right up. 

Aluminum towers can't rust, of course, 
and never need any paint. They look great 
when you put them up and look just as great 
years later. 

For a catalog and prices send to Micro- 
fleet, 3575 25th S. E,, Salem, OR 97302. 

73 Tests the Gfobeplotter 

One of the cleverest ideas for beam 
aiming at DX to come along in recent times 
is the Megert Globe Plotter, Tliis consists of 
a six inch world globe sitting up on a 
pedestal with a beam-path indicator. 

To use this gadget all you have to do is 
turn the globe so that your station location 
is beneath the locating circle on the top of 
the stand. Then* as you turn the pedestal, 
you can read the beam heading of any city 
that falls under the beam-path indicator. 
Charts and regular world globes are all well 



112 



73 MAGAZINE 




^ 



and good, but there is absolutely nothing 
like having a globe mounted with your home 
on its axis. For the first time you will be 
able to see how the great circle paths really 
swing.,, and how your signals travel. If youVe 
ever wondered why your beam heading is 
almost the same for Brazil as it is for South 
Africa, the question will be dispelled when 
you swing your Globe Plotter around. 

Andj since the globe is not permanently 
fixed in place (unless you glue it to the three 
pillars that hold it to the pedestal) you can 
easily swing it around to any other location 
and get the beam heading from there to any 
other spot in the world. If a station in 
Germany is working New Zealand, do you 
think he could here you? The plotter will 
tell you immediately. 

You don't have to scrunch over to see 
what the other side of the world is iike.„GP 
has a built-in mirror for looking at Australia 
and environs. 

The Globe Plotter is just under 10" high 
and is mounted on a nice looking base. Price 
is $17.95 by mail order from Megart^ Box 
2097, Des Moines, Iowa 50310, 



Does Math scare you? 
"Simplified Matli for itie Ham Sliack" 

One of Us books will make it easy. 
Order today, only 50c. 



PROPAGATION CHART 

J, H, Nelson 

October 1969 



SUN 


MON 


TUE5 


WED THUft 

©0 


FHI 

3 


SAT 

4 


0® 


7 


S 9 


10 


© 


@ 


@ 


@ 


©@ 


17 


@ 


@ 


i@ 


21 


@@ 


@ 


25 


26 


27 


@ 


@@) 


® 





Legend: Good O Fair (open) Poor D 



EASTERN UNITED STATES TO 



CttT: IM VI U4 



tie. 



ii'i 



m 12 



14 



li 19 za 22 



ALASKA 


^ 1 


U 


7A 


1 ■*- 


^ 


■r 


1 


L 


14 


HA 


21 


21A 




AHtit.STtS^A 


'2 ■ 


H 


14 


1-s 


7 


7A 


TA 


I4A 


£1a|2:\ 


2lA 21A 




At*£iTftALtA 


2IA 


H 


7A 


m 


TB 


70 


TB 


TB 


14 


1 t 


?tA 2B 




CAPITAL ZOSE 


H 


N 


14 


7A 


7 


7 


1 


14A 


2H 


2tt 


2a 


21 A 




F; N L A N D 


7 


7 


7 


7 


7 


7A 


7A 


14^1 


atA 


21A 


^t 


M 




1 [ A W A 1 J 


11 


U 


7» 


7B 


7 


1 


7 




14A 


2tA 


2H 


2H 




INDIA 


ll\ 


W 


7[l 


7B 


7B 


IB 


m 


£4 


H 


14 


1 14 


TB 




JAPAN 


H 


H 


1413 


7B 


IB 


1 


7 




7d 


7B 


I4e 


21 




M£XtCCi 


TV 


H 


14 


7 


T 


7 


r 


14 


21A 


2)A 


21A21A 




PHJLiPPI^itS 


21 


14 


14B 


TB 


7B 


7B 


TB 


TB 


14 


14 


14fi 


14 




l^t'EHTO HICO 


H 


7A 


T 


7 


7 


7 


7 


14A 


21 


21 


21 


21 




SOUTH AFRICA 


14 


14 


H 


14 


IB 


14 


14 


2tA 


2:^ 


2a 


21A 


21 




U- 5, i. H. 


7 


1 


7 


t 


? 1 


7B 


75 


14A 


21 


14 


If 


-^B 




WEST COAST 


2\ 


14 


H 


1 ''^ 


7 


' 


-p 


7 


2; 


21 


2 LA 


21A 




















CENTRAL UN 


IT 


ED STATES TO: 


















A L A ii K A 


21 


H 


14 


£ 


7 


7 


1- 


■; 


1 T 


21 


21A 


21A 




ARGENTINA 


21 


14 


H 


14 


7 


1 


3 4.A 


lb 


21A 


2IA 


21A 


21A 




AUSTKALIA 


za 


21 


H 


7A 


7G 


7B 


7B 


14B 


14 


14 


21A 


28 




C A S A L I a?i E 


2\A 


U 


14 


H 


■T 
•1 


7 


1 
14 


21A 


28 


?* 


3B 


2S 




ENCiLA^*0 


7B 


1 


7 


1 


7 


'IB 


t4 


21 1 


21A 


2JA 


14 


14 




KAWAtl 


2& 


n 


14 


7A 




7 


i 


7 


14A 


2JA 


38 


S@ 




INDIA 


]4 


14 


7A 


7B 


70 


1[\ 


TB 


14 


H 


14 


14 


14B 




JAPAN 


21 


H 


H 


TB 


7B 


7 




7 


7B 


7H 


H 


2t 




M F X i C O 


11 


14 


7 


7 


7 - 


7 


7 


14 


21 


n 


21 


21 




PHlUPPlN tS 


21 


L-1 


\'\ 


TB 


713 


7B 


TB 


70 


14 


M 


14 


21 




PUERTO KICO 


2\ 


M 


7A 


7A 


7 


7 


14 


ai 


21A 


2tA 


21A 


21 




SOUTH AKtttCA 


H 


H 


14 1 


7B 


7B 


7B 


14.4 


2\ 


2« 


M 


?1A 


^i 




U. S. S. R. 


TH 


7 7 


f 


T 


7B 


7B 


14 


_Li^ 


1^ - 


14 


7B 






WESTERN UN 


IT 


ED S 


>Ti 


\TES TO: 




















ALASKA 


z% 


14 


14 


7 


1 
t 


7 


7 


T 


14 


l4Aj 


l\ 


31 




ARGENTIJ^A 


21 


21 


14 


H 


14 


TA 


TB 


14A 


21A 


2iA 


2tA 


21A 




AUSTRALIA ■ 


U 


2S 


£1 


M 


14 


14 


71) 


7 n 


H 


14 


2iA 


?fi 




CANAL ifiONE 


21A 


21 


14 


14 


7 


7 


7 


14A 


S|A 


2ti 


26 


28 




ENGLAND 


IB 


7M 


7 


7 


7 


75 


7B 


H 


21 


21A 


H 


H 




RAWAtr 


26 


2E 


21 


14 


H 


7A 


7 


I 


Mfi 


21A 


2{Y 


3P 1 




INDIA 


14 


t4A 


14 


7B 


f^ 


7D 


7B 


7H 


14 


14 1 


14 


141 




JAPAN 


21A 


21 


14 


TB 


_Ifi 


7 


T 




? 


7B 


H 


ZlA 




MEXICO 


21 


2t 1 


14 


1 


, 


7 


7 


n 


21 


2! 


21 A 


?,]fk 




PHtLlPPlNES 


ZtA 


21 ] 


14 


1 
TB 


71^ 


TBi 


7B 




11 


14 


H 1 


n 




PUERTO RICO \ 


n 


H : 


14 1 


■ 


7 


^ 


- 


jAi 


2IA 


2h 


26 


^lA 




SOUTII AFRICA 


14 


14 1 


[4 


IB 


,B 


m 


_1E_. 


14 


21 


21 


SIA 


21 




U, a. fi. R, 


"B 


VM 


■ B 

i 


TB 


7H 


Tt^ 


Tp 


IR 


H 


14 


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\\ ! 


14 1 


4 


7 


7 


-J_ 


J 


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21 


21 


21A 


21A 





A-Next higher frequency may be useful this period 
B— Difficult current this period 



OCTOBER 1969 



113 



used to coat 



Across 

1 . Also called a ham* 

4. Electronic path be- 
tween 2 or more paths 
providing a number of 
channels, 

7, Type of tree. 

8- Logarithniic expres- 
sion of ratios of 
power. 
10. Ampere, Abbr. 

12. Electromagnetic unit. 
Abbr, 

13. A generator that pro- 
vides field current for 
an AC generator. 

14. Organ of sight, 

15. Megohm. Abbr. 
17. Basic unit of work in 

the cgs system. 

19. Period immediately 
before some event. 

20. Surrounding. 
23. Used in T.V, receivers 

to supply high DC 
voltage required by 
the second anode of 
cathode-ray tubes, 

26. Chemical compound 

recording discs. 
28. Audio amplifier frequency equal to the 

square root of the product of two 

half-power frequencies. 

30. Maiden name. 

31. International Radio Association, Abbr, 
33, G.l. club. 

35. Affirmative side. 

36. A type of battery, 

37. To move with pressure and friction. 

38. Short sleep. 

40, Surface between two adjacent grooves 

on a recording disc. 
42- Period of time. 

43, A device that introduces inductive 
capacitive reactance into a circuit. 

44. Process of entering information 
answers via the agency of a printer. 

Down 

1. A means for radiating or receiving radio 
waves* 

2. Short wires used to connect open-line 
wires to insulators. 

3. Stepping relay actuated by an arma- 
ture-driven 

4. Prolonged undesirable opening and 
closing of elecrtical contacts. 

5* Used in mechanical push-button tuning 
systems. 




or 



or 



6. Speaker designed for treble frequencies. 

8. Worthless person. 

9. A section or branch of a component or 
system, 

10. Unit of surface measure in the metric 
system. 

11. A sliort pin or bolt. 

16. End section of a transistor. 
18. Also called diamond antenna, 

21, Male nickname, 

22, Partner of bolt. 

24. Weekday, Abbr, 

25. Indefinite period of time. 

26. A fitting designed to change the termi- 
nal arrangement of a jack, plug or 
socket. 

27. Sometimes called matrix, 

28. Absolute unit of pressure. 

29. A type of dipole antenna. 

31, Atom which has fewer or more elec- 
trons than normal, 
iJt^ oinaKe. 

33. Stations capable of direct communica- 
tions on a common channel. 

34. A globe or sphere. 

39, Discharge of electricity through a gas, 

41, Also. ^,, ^ , ^ 

. . , Michael Kresila 

SoluVion on p^qB 122 



114 



73 MAGAZINE 




The ESSCO Mode* TU-7 Teleprmter 
Deinodulator is a completely assem- 
bled, ready to run system, fufly wired 
with loop supply, connectors, tuning 
indicator, reversing switchi modufar 
tracks, scope outputs, 50 ua 2ero 
center meter, function switch and 
famous ESSCO solid state modular 
plug-in units. 



*0»ii 



■♦■^^^ 



ESSCO's Complete 

SoUd St<sUe 



RTTY DEMODULATOR 



TU-7B DUAL CHANNEL KfT 

TU-7 (As above) Factory wired, tested & guaranteed 

TU-7C SINGLE CHANNEL KIT 

TU'7D (As atx}ve) Factory wired, tested & guaranteed 



$138.25 
$163.00 
$132.25 
$156.25 



Model TU-7C 



'* uelet^e SpecialiAts' 

324 ARCH STREET CAMDEN. N. J 



Phan«: (609) 36S-6in 



a dollar a copy? RIDICULOUS I 



It may be rrdfculous, but it is also not far in 

the future. The dollar won't make us rich, either. 
We hope that it will bring us back into the black, 
and thaf^s about it. 

What happened to bring on this substantia! 
increase? Two things. First and foremost was the 
July increase in postal rates. This was the biggest 
rate increase yet for us , . . and we are paying 
over 50% more in postage now than we were a 
year ago* The 5% profit we made last year just 
broke us even with inflation, so we found 
ourselves working like the devil to break even. 
Now, with the new postal rates, we will work 
ourselves sitly for a handsome net loss. Something^ 
has to qi\f& * . » and that means you, the reader. 



# • • 



NAME 



it fs not all g?ve and no take, by any means, 
however. Just look at the size of this issue of 73. 
We've been running 144 pages a month or better 
since May and intend to keep it up. When you 
figure that we are, month after month, bringing 
you more feature articles than all three other 
magazines combined, then the quarter extra isn't 
all that bad a deal. 

Of course there is still time to hedge against 
the increase by buying a subscription right now, 
before the subscription rates go up, too. We'll 
accept a three year extension of your present 
subscription at the current rates . . , but don't 
expect to be able to take advantage of this for 
much longer. By next month we may have to roll 
out the new subscription rates for you. 

CALL 



ADDRESS 

STATE 



CITY 



D I WANT THE $12 BARGAIN RATE FOR THREE YEARS 

D IXL TAKE ONE YEAR AT THE $6 RATE 

D THIS IS A RENEWAL 

D ENCLOSED IS CHECK. CASH OR MONEY ORDER 

73 MAGAZINE PETERBOROUGH, NEW HAMPSHIRE 03458 




OCTOBER 1969 



115 



man 



A. David Mtddelton W5CA/V/7ZC 

Box 303 

Springdale, UT 84767 






or The Tale of Two Kitties 



I should have realized what was going on 
when those QSL cards would not check out 
with my log! My memory did not include 
any recollection of QSOs with those 
stations, and there were no entries for them 
in my log book. 

Before getting any deeper into my 
problem, let me explain the W5CA station 
set-up. My garage-han>shack is a Santa Fe 
railroad boxcar, of the old wooden type. It 
is 44 feet long and makes an excellent garage 
for my Buick. By adding a partition 1 made a 
cozy hamshack and workshop in the end of 
the old box car. The shack has comfortable 
old chairs, a battered sofa and^ of course, the 
rig and workbench, plus tlie usual pile of 
surplus gear. 

The YF and I are cat lovers and have 
always shared our home and household with 
cats. Currently we have two furry friends; 
Golden Nugget 3rd, and Ebony, a jet black 
cat two years younger than old Nugget who 
is twelve. Both are fine cats and friends. 

Long ago, I thought up a convenient 
method of letting our cats in and out of 
their quarters. I cut an opening in an outside 
wall, overlaid with pieces of canvas to keep 
out the wind- unwanted dogs, and yet 
permit the cats to go in and out of their 
home without bothering us. Such a "cat 
door'* was placed in the tjox car wall so that 
the cats would have a snug, warm place to 
sleep or to hide out. The only human access 
to the shack is a door that is kept locked to 
protect the rig from "unauthorized usage". 
Or, so 1 thouglu! 

1 practice the old habit of leaving all 
filaments burning on the rig and the receiver 
fully fired up. All it takes to get on the air is 
to punch a push-button switch on the table. 



This energizes the input to the transmitter 
power supplies. A foot switch, when pressed, 
completes the relay circuits and the rig is on 
the air, subject to keying. With the fool 
switch up, the receiver is back in action. As 1 
said before, 1 should have known better! 

Looking back, I recall that Nugget spent 
an awful lot of time in the shack. 1 presumed 
that both cats slept there at night but, even 
in the daytime, there was usually a cat 
snoozing away on the sofa or in one of the 
old chairs. 

Nugget was also a frequent guest on the 
operating table. Tliis began when he was still 
a small kitten. He was fascinated by the 
IIRO dial and entranced when the colored 
pilot light jewels lit up. The Panoramic 
adapter 'scope pattern seemed to attract his 
attention and the wiggles of the 'scope 
pattern almost hypnotized the cat. He would 
sit by the hour and watch. As he grew older^ 
liis long whiskers would twitch as the CW 
screeched out of the cans perched high on 
my head. Ebony was not so impressed and 
gave the rig and its operation scant 
attention. 

Another thing I should have noticed was 
Nugget's staring at the QSLs pinned on the 
wall and ceiling. He'd sit by the hour, golden 
head cocked to one side, peering at the cards 
with their bright numerals and hitricate 
patterns. 

Then one day 1 added a new one- 
FEIINE. Shortly after this, things began to 
happen that were beyond my comprehen- 
sion. I have always, like most active 
amateurs, received a few QSLs that would 
not check out. Even inactive hams some- 
times receive them! Fd had my share of 
unknowns, but now there were more than 



116 



73 MAGAZINE 





normaL 1 pile up my incoming cardSj and 
some evening when the band is dead I sort 
them out, check them against the log, record 
their receipt and then fiU out answers. 

This one evening there were several cards 
which would not fit into my records. There 
were the usual W and K cards, many of 
which were from guys so anxious to work 
New Mexico that they overlooked making 
the^ necessary QSO first. But there were 
several DX cards in the pile and they did not 
show up in the log. This should have been 
warning enough, but as I said, I was not 
hep" not yet! 

I filed away those inexplicable cards with 
my collection of swl cards, sighing as I did, 
for there were some really rare ones in this 
new group of "unknowns**. 

A few days latex our 5th call area QSL 
Bureau sent me another batch, and with 
those cards was a scribbled note from Brad, 
W5ADZ, our QSL sender-outer and noted 
DXer. His note read-"OM, you sure have 
some goodies in this batch. This makes me 
drool to see such choice morsels go out to 
you. What special calling formula do you use 
at Tijeras, or is it merely the altitude? 
Lemme in on the secret/* 

I spread out this new batch of cards 
which had evicted a comment from blase 
Brad J who, I thought must have seen 
everything in the line of DX himself. No 
wonder Brad had mentioned these cards. 
Here is the list, just as I wrote them down on 
the back of a log sheet, ME^UW-URIKAT- 
CAITS" PU3SS- MJJUSE- YLIKIT- 
UPIPUS! I was sitting there mulling over 
these rare cards when I chanced to look over 
at the old sofa. Ebony was asleep but Nugget 
was obviously "playing possum". I could see 
his eyes gleam through narrowed lids. He 
was far from asleep.! I had been picking up 
the cards, one by one, examining them, and 
then I placed them face up on the table. 
Nugget looked as if he was watching me, so I 
tested him by holding up the colorful 
YLIKIT QSL. Nugget's long white whiskers 
twitched and I could see him drool, as cats 
do when they are pleased or excited about 
something. The look in the cat's eyes was 
enough to tip me off, but how dumb can we 
humans be? There was still another clue to 
the mystery but I muffed it, also. At W5CA 



I use an elapsed -time meter across the ac 
input to the transmitter plate supplies. This 
meter records the actual time -on-air of the 
transmitter. I took a look at the readings for 
the past few months. My figures showed that 
there was more time on the meter than a 
quick inspection tallied on the log. But, 1 
merely made a mental note to keep better 
records and put down the discrepancy as 
lousy bookkeeping. 

I continued to wonder about those 
"goodies" as Brad called them and regretted 
the fact that they could not be counted in 
any awards or totaL I did not even recall 
hearing such stuff as ME0UW, although 
there had been some really screwy calls 
issued in the past few years. Yet- there was 
something that bugged me about those 
QSLsf 

A few evenings later I got out those 
strange cards and spread them on the table. 
Nugget was sitting on the end of the 
operating table looking out the window, I 
noticed that he kept slyly turning his head 
to watch me lay down the QSLs. When I put 
down the pretty one from YLIKIT I saw a 
furry paw reach out and give the card a pat I 
The paw drew back lightning-quick as the 
cat obviously did not wish me to see his 
actions. He sat there- silently and with not a 
whisker twitching. Then he resumed looking 
out the window. 

Suddenly, as it so often does, the band 
came alive and KAITS came blasting in, the 
cans screeching out his call. The KA signed 
and I looked at Nugget. His eyes were open 
in a wicked fashion. His right front paw 
stiffened and reached out toward the key. 
The cat started to tap on the Navy knob! 
Shocked speechless and motionless, I just sat 
there. Nugget saw me stare at him and drew 
back his paw and began a careful inspection 
of the sheathed claws, completely indif- 
ferent to my bewildered glance as he took 
refuge in a routine cat-type operation- paw 
inspection. 

1 have been a ham for over forty years, 
boy and man, but what followed is the 
weirdest thing 1 ever had happen to me! 

Startled, I said out loud, "I'U be-'\ A 
furry paw shot out and I heard the key click 
out "BK BK*' as the cat manipulated the 
key. 





OCTOBER 1969 



117 



1 

•4 



Incredible thoughts raced through my 
brain- Could my pet understand what I say? 
To test liim, 1 spoke out firmly, "Look here, 
Nugget! Can you understand my speech? 
Can you send Morse code?" 

He did not hesitate. The cat's paw acted 
and the key clicked "C'\ 1 gasped and 
muttered, half to myself, "Oh, a traffic 
man!" 

"Not me, OM" came the clicked reply, "I 
just know all the tricks." The cat looked 
smugly at me as I sat there bewildered and 
amazed. 

As I sat there looking at my unbelievable 
pet he jumped from the table to the work 
bench where there was a transistor code 
practice set. He stood over it staring, until I 
reached for it and picked up the set and put 
it on the operating table. Nugget immediate- 
ly moved close to the practice key and sat 
there- waiting, 

I saif out loud, **Let's get this matter 
straightened out." I paused and continued. 
**So you understand when I speak to you?" 
Then came the answer that almost rocked 
me from my chair. "Sure, OM, Ail us cats 
dig English," The tiny loud speaker on the 
code practice set rang out this unexpected 
reply as the cat skillfully manipulated the 
key, 

"How long have you understood human 
talk?" J I quickly queried the cat, 

"That is the second most important thing 
we learn. First comes eating, and then comes 
language." The cat seemed very sure of 
himself as he pounded out the code in a 
precise fashion. 

"Why don't you ever speak to us?" I 
inquired, 

"We do, but you dumb clods can't hear 
us cats talking!" The golden-furred face bore 
a smirking look. I could see I was being 
forced into a corner, so 1 tried another angle 
of attack, 

'Took here, Old Cat, What about your 
operating on code? Isn't that unusualV^ 

'Well, OM. I am getting through to you 
on CW, Right?" 

**How about the rest of you cats?", I 
asked my pet- 
Nugget drew himself up proudly and 
replied in well-sent Morse: "That is a 
different story. Very few cats can pound 



brass. Most cats are 'tone men'. If you don't 
believe it, just listen in on any phone band 
and hear all the cat-calling and squeals, 
especially on AM fone." 

I muttered to myself, ''He*s got some- 
thing there!" But, being undaunted, I 
plunged in even deeper as I queried, "How 
did you learn the code?" 

^'It was this way. You always leave the 
receiver going full blast. Right? And, you 
know how some signals just seem to drift 
back and forth across the dial?" 1 knew just 
what he meant. 

The cat went on, **That is the way I 
started. I lay here trying to get some rest 
after a hard night out^ but that CW kept 
whistling in my ears, Vd hear a station call. 
Then another would answer him. I got so I 
could read letters. Then came whole calls 
that I could catch. Finally, 1 got so I could 
copy whole QSOs." The cat stopped and 
looked at me, but I said nothing so he went 
back to his brass pounding- 

"Soon as I got *over the hump' it was 
easy, OM. Later I found out about tuning 
and happened to tune in a code practice 
session. Then, I listened whenever 1 could 
hear Wl AW and W60WP. That is when some 
lid did not smother their code practice 
transmissions with QRM. Say? OM! Do you 
think I could get a Code Proficiency 
Certificate from ARRL?" The golden-haired 
puss looked up at me, with great pride in his 
huge yellow eyes, 

"Come now! You don't think I believe 
that you have qualified for a CPC." I did not 
give him a chance to reply but pushed right 
on into my next question. "How did you 
learn to send?" 

Back came a snappy answer in the form 
of another question. My cat was up to 
people-type tricks! "How did you learn?", 
he sent. 

Without thinking, I replied, **Why, all us 
Young Squirts learned by tapping out code 
on a desk or table with our fingers." I 
looked at Nugget who did not seem 
impressed, so I added, "We even had QSOs 
that way." 

"Why not?", snapped the cat, "IVe tried 
lots of times to raise you, but OM, you sure 
are slow on the up beat!" Then the cat really 
set me back on my heels as he told me his 



118 



73 MAGAZINE 





theory of learning the code, "Once my 
subconscious mind had mastered the code it 
was easy for it to transfer this ability to 
digital functions and what happened? I 
could pound brass as well as receive." The 
cat's face was full of smugness as he sat back 
and waited for my reply, 

"Was it you, Old Cat, who ran down the 
batteries in the code practice set?" I asked in 
an accusing tone. 

"Sure, I had trouble operating that little 
switch so I just left it on all the time/' 

"So- you learned to copy and to send 
CW, Now tell me, how did you work the rig 
and the receiver? What about the foot 
switch, Old Cat, how did you use that?" 

I looked so scornfully at my cat that he 
lowered his head but tapped out, "Ebony 
was my second operator and foot-switch 



mam 



ff 



1 looked around for the black pussy cat. 
Ebony, but he was not in the shack. The 
golden-furred paw went on and continued to 
send flawless code to tell me this amazing 
story, "I tried to get Ebony to learn the 
code so he could operate as weU as I, But he 
would not practice and he thought it was 
not worth the effort. Oh, he learned to read 
and to send calls, and he could even hold a 
simple QSO. But, let's face it* He was never a 
hep cat on CW-" 

"Tell me. Nugget, How did you work the 
rig? The foot switch? That takes coordina- 
tion!" 

"OM, I sit in front of the receiver, like 
this." The big cat moved over in front of the 
HRO and put one paw on the huge diaL This 
dial turned easily due to its well-wom 
smoothness through years of use. The cat 
moved the dial with practiced ease. He then 
returned to the practice set and sent, "That's 
the way I tune the receiver. Then 1 hit the 
key at just the riglit instant." 

"The foot switch? What about that?" I 
implored. "How did Ebony know when to 
press the switch?" 

**We cats have our own private means of 
communication and it sure beats electronics. 
Not a tube or even a transistor," The cat 
seemed to sneer as he manipulated the key 
with precisely-formed characters, 

I had no reply as that comment only 
substantiated what I had long believed about 



OCTOBER J969 



animal communication. 

The cat went on sending. "I tell Ebony 
when to press the foot switch and he knows 
from my sign off when to release it*" 

I had about reached the limit of my 
credulity and was about to blow my stack 
but 1 took one more chance and ordered- 
"OK! Old Cat, let me see an actual 
demonstration/* 

Nugget shrugged a whisker and reph'ed on 
the key, "Why waste the juice? You know 
the band is dead/* 

I was in no mood' to argue with a cat. 
**Never mind that. I want to see you operate. 
Dead band or live band. Hop to it! '* 

'OK, OM. If you insist- QRX one." 
Nugget jumped from the table and darted 
out the cat*s door to the outside. In a few 
minutes he was back close-herding a 
reluctant, paw-dragging Ebony, The black 
cat crouched on the floor beneath the 
operating bench, obviously st0 half asleep. 
Ebony looked up at me with a mournful, 
resigned look. This being drafted to help 
operate was nothing new to him and not 
very pleasant either, his sad eyes impMed, 

Nugget said something in cat talk to his 
assistant operator which, naturally, I could 
not hear. Ebony moved over and crouched 
near the foot switch. There he sat, 
Sphinx-fashion, paw on board, waiting a 
command. 

Let's see you cats raise someone. Any 
one!" 1 demanded. 

Nugget smirked at me, whiskers twitch- 
ing, but moved to the HRO and sat up on his 
hind quarters. With infinite patience and 
considerable finesse, he slowly rolled the dial 
by applying paw pressure to one side. 1 
heard a loud signal calling CQ< The paw 
stopped and the CQ ended. It was K9DOG. 
The signal was loud and clear. The cat 
ignored it and continued tuning over the 
band. Puzzled, I inquired, "Why not him?'* 

Nugget jumped to the practice set and 
repUed, "OM, we cats do have our pride." 
Then he strutted back to the HRO. Tuning 
around he brought in another CQ and the 
letters of the call were C A T. The 
cat-operator slipped a paw and nudged the rf 
gain control. The signal rose to a more 
readable level and the cans rattled out the 
code. Nugget raised up, pressed the spotting 



119 



C£' 





1 



1 




Micro-Switch on the vfo and, with his other 
front paw^ carefully tuned the variable 
oscillator to zero beat. Then he relaxed, paw 
on key until the stated signed- It was 
K8CAT. 

My two pets^ by their own communica- 
tion method undetectable by humans, were 
in contact and ready to go into action. The 
black puss was almost asleep, and relaxed, 
but at just the proper instant down went the 
black paw, the foot switch closed, relays 
clattered and W5CA was on the air! I 
watched speechless with amazement! 

Nugget tapped out a sharp 3 x 3 call and 
sent AR, His co-operator under the table 
raised his paw, the relays snapped over into 
"receive** position and I heard K8CAT come 
back with a good report to which he added, 
"You must be a visitor at W5CA. That fist 
does not have Mid's Lake Erie swing." 

1 could stand this incredible sequence of 
events no longer so I reached for the key, 
iust beating Nugget to the Navy knob by a 
whisker*s width. I sent/*rfti!T is Mid* The 
other operator was my cat." I stood by, 
TliciL was a long pause— 

"Did you say your c,a,t?" inquired the 
distant 8, 

*'Yes, OM." 1 repeated, "my cat." 1 
looked over at Nugget who was now engaged 
in a microscropic examination of his left 
paw. He showed only indifference on his 
golden face. I looked down at the black cat, 
Ebony. He was still crouched at the 
foot-switch with a paw in the "ready" 
position. 

K8CAT was still unconvinced as he asked ^ 
**You mean a feline animal? A pussy cat?" 

This time Nugget's paw beat my hand to 
the key and he replied^ "Sure— a cat. I am 
twelve years old, name is Nugget. I have a 
golden coat and a long fluffy tail BK." 

There was a vast quiet on the frequency. 
Then came a stuttering sound of characters 
incoherently formed. Finally the dots and 
dashes dribbled off into gibberish. Then— 
more silence and lots of it! 

Nugget looked at me and I am sure he 
shrugged his whiskers. His look said-well, 
that guy just could not take it. The cat 
seemed unmoved by the distant amateur's 
confusion, 

I reached for the log book to record the 



ill-fated QSO with K8CAT. Tliat action 
brought back a flood of memories and raised 
some pointed questions in my mind. What 
about those uncheckable QSLs? Such an 
event could have brought in QSLs from 
those "unknowns". 

Then the shack roof fell in on me! 
ME0UW-M?)USE and YLIKIT! Could it be 
that my cat operators were that selective? 

The golden cat moved over to the 
practice key and resumed our cross-band 
QSO in his excellently-sent code. "Only the 
good DX. Ebony worked some of the locals. 
He does not dig DX like I do. Besides, he has 
a lousy fist-1 mean paw. I don't let him 
operate often," 

I glanced at Ebony but he appeared to be 
sound asleep. Perhaps he was and had not 
heard Nugget's slanderous remark, or per- 
haps the code was just a bit too fast for him, 

"Perhaps, OC," I continued, "y*^^ wquld 
care to tell me how you learned about bX 
and what is choice DX?" My voice was mofe 
respectful as the awsome facts began to sink 
in. 

'i read QST's *HOW'S DX\ You always 
leave the magazine open at that page, OM" 
sent my intelligent pet, 

"Now, Nugget!" I said with triumph in 
my voice, "I've got you! It takes a 
magnifying glass to read that fine print in 
QST," 

"BK-" sent the cat, '"^you know that us 
cats are very proud of our keen eyesight, 
Why^ OM, I can even read the addresses 
listed in the call bookV^ Nugget was really 
smirking now. 

That did it! I realized that this discussion^ 
while enlightening, was not placing human 
beings in a favorable light. I leaned down 
and picked up the sleep -limp Ebony. I 
placed him by the practice key and said, 
"Let's hear your fist^ Ebony!*' 

Nugget must have said something to 
Ebony. The little black cat put out a stiff 
paw and slowly tapped out in uneven 
characters-"Ur s igshere 5 59Q T HTijer as 
Ne w Mexic o handlehereEbony how cpyb k 
toyou," Ebony relaxed in a heap beside the 
key. 

Nugget shot out a paw and sent briskly, 
"You see what 1 mean, OM He has listened 
to and worked too many Novices." The 



120 



73 MAGAZINE 




RCA TV-EYE. See QST Nov. 1962 for 

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PO Box 85, Longview St; 



golden-furred cat seemed almost ashamed of 
his companion's inept operating skill. '*But", 
the sending continued, **he is really a sharp 
foot-switch man/* 

i was chagrined at aU these proceedings 
but yet I was determined to add some 
reproachment for the cats 'actions. "Look 
here, you furry scoundrels. What about FCC 
regulations regarding 'unauthorized opera- 
tions'? What about Rule 12.1?" 

Nugget broke me on the practice key and 
replied. **You mean where it defines an 
*amateur' as a person interested in radio 
technique? The FCC cannot bother us cats. 
Cats are not persons!" 

I could think of no fitting response to 
that obvious truth so I pressed on to another 
point. "How come you never filled in the log 
or answere any of those QSLs?" My 
questions were almost a sneer. 

Nugget's reply was the coup de grace as 

he snapped back. "Who ever heard of a cat 

who could writeV 

. . . W7ZC 



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REOLINE Co., Box231,Jaffrey, NH-03452 






OCTOBER 1969 



121 



I 



Save That Manual 

Every ham who has been actively associ- 
ated with the hobby for any appreciable 
length of time has around the shack a multi- 
tude of rigs, rotors, and test equipment 
which requires occasional maintenance of 
one type or another. When the equipment 
was new^ the last thing on the owner's mind 
was a future need to refer to the instruction 
and /or service manual. All too often it is 
tossed into a comer and forgotten- Comes 
the day service is necessary or a sale immi- 
nent and the manual is not to be found. 

One excellent way to keep this valuable 
information at your fingertips is to place all 
such data in a three-nng notebook (threes 
ring because smaller manuals will still be 
held by two of the rings). The dime-store 
variety binder will do nicely. While there, 
also buy a set of inexpensive dividers^ and 
label each with a type of equipment. Having 
separate sections fox the various types of 
equipment will speed your progress when 
you need a particular manual. 

A second method, which I find to have 
advantages, is to buy a separate folder for 
each piece of equipment- The cardboard 
type with three double metal tabs is avail- 
able at your local stationery store in various 
colors- In this shack red indicates transmit- 
ters, black is test equipment, grey is anten* 
nas, rotors, and other outside hardware. A 
typed, gummed label on the cover indicates 
the exact contents. These folders may be 
neatly kept on a bookshelf where they will 
be easy to find* The uniform size and the 
color coding make the shack take on an air 
of neatness which could well become con- 
tagious. William P, Turner, W A0 ABI 







Solutio 


n to puzzle on page 


114 


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122 



73 MAGAZINE 





Kn igh t 



V-107 VFO 






Two Meters 



Just finished the Knight-kit V-107 VFO 
and it took me one hour to do it. Would you 
believe two hours? Honestly it took me 
three hours by my stop watch to assemble, 
wire and calibrate this VFO. Time was not 
essential, but I was anxious to see how long 
it would take to complete the kit and have it 
operating- 
Assembling the Knight-kit V-107 VFO is 
so simple that any previous experience is not 
necessary. The instructions in the manual 
make every step of construction easy to 
follow. The text and pictures show exactly 
where each wire or component fits in. Yes, 
the wires are even cut to length, stripped and 
ready for soldering- \% you are not an expert 
on soldering now, there are some exceUent 
lessons in the construction manual which 
will make you one. 

The V-107 VFO is usually sold as an 
accessory for the TR-106 and TR-108 
Knight-kit Transceivers but it can be used 
with any 2 or 6 meter transceiver or trans- 
mitten It uses the Clapp oscillator (some^ 
times known as Colpitts) for maximum 
stability and has a high L/C ratio in the tank 
circuit, resulting in less drift. The output of 
the VFO has a minimum of 20 volts RMS 
which is enough to drive most any trans- 
mitter for the 2 and 6 meter bands. A 
high-gain pentode, I2BK6, is used for the 
oscillator tube and a voltage regulator tube, 
0A2, is used to stabilize the voltage on the 
screen of the 12DK6. 

Cahbrating the V-107 is no problem if the 
step-by-step instructions are followed in the 
construction manuaL You will find it just 
takes three important adjustments, L-1, L-2 
and C-2, to calibrate the VFO for either 2 or 
6 meters. With these adjustments finished 
you are ready to work anybody on these 
bands and be on frequency of any station. It 
might be suggested that these calibration 
adjustments be made after a thirty-minute 
warm up to make sure they are correct. 



Ralph Steinberg K6GKX 
1 10 Aigonne Avenue 
Long Beach, CA 90803 



Power requirements are 200 volts DC at 
30 ma and 12.6 volts AC at 150 ma for the 
I2DK6 oscillator tube and can be supplied 
from the TR-106 or TR-IOS Knight-kit 
Transceivers. Should the VFO be purchased 
separately, power can be taken from the 
transmitter or transceiver of your choice. An 
outboard power supply with the same 
voltages win do as well. 

When the V-107 VFO was finished, "on 
the air" workouts were done to check drift, 
temperature and mechanical stability. On 
drift it was minor and in line with the 
specifications of the manufacturer, AUied 
Radio Corporation. For temperature, it was 
cool as cucumber and this is due to power 
levels kept at a minimum allowing for very 
little heat dissipation. The mechanical sta- 
bility can be said that the V-107 is mgged 
and designed hke the well known expres- 
sion . • . ''just like a battleship," 

Two different 2 meter transmitters were 
used for checks on this VFO and in each 
case there was plenty of drive and it operated 
the '*rigs" satisfactorily. Much of this was due 
to keeping the output cable of the VFO 
short, as recommended in the construction 
manual 

For the ham that has just a few crystals 
to operate on the 2 or 6 meter band, the 
Knight-kit V-107 VFO just cannot be beat at 
the price of $24,95, 

. ^ . K6GKX 
Technical Specifications 

Frequency coverage: 8.333 to 8.666 mhz for 6M; 

8.000 to 8.222 mhz for 2M. 

Frequency stability: +/-500 cycles per hour 

after 30 minutes, 

RF output: 20 volts rms minimum into 47K/30 

pf. 

Power requirements: 200 vdc ^ 30 nia; 12.6 vac 

fe 0.15 amp. 

Tube compliment: 12DK6 oscillator; 0A2 volt- 

age regulator. 

Cabinet size: 5Vr x 4-5/16" x eVi". 



^ 



OCTOBER 1969 



123 



Careers in the 




Sam Kelly W6JTT 

12811 Owen St. 

Garden Grove, CA 92641 



Looking for a way to combine a career in 
electronics with adventure and above average 
earnings? Want exciting work on a tropical 
island, a tracking ship on the high seas or in 
Europe? If so, you should look into the 
opportunities in field service. 

Field service (also called field en- 
gineering) provides technical support and 
operating personnel for equipment after it 
has left the home plant. As you can guess, 
the U, S. Government is the biggest 
customer for electronics equipment and field 
services. The government needs technical 
help to keep the vast amounts of electronic 
equipment associated with our space 
programs and weapon systems operating. 

Besides private industry, many branches 
of the government operate their own field 
service organizations. An example is the 
Federal Aviation Agency (FAA). The FA A 
maintains an excellent field service organi- 
zation that performs such widely diversified 
tasks as making radar surveys to determine 
the best locations for long range radar 
stations to the installation and check out of 
the latest digital computers. Many other 




I EC Field Service Engineers prepare a port- 
able telemetry system for a polaris tracking 
mission at sea. 



government agencies operate similar services. 
Field service organizations have openings 
for job skills ranging from engineers to 
electronic assemblers. In general most hams 
would be interested in becoming engineers 
or technicians. 

This is one of the few fields where a man 
can still work into an engineering job title 
without a degree in engineering. However^ 
this is rapidly changing. If you are planning 
on becoming a field service engineer you 
should obtain a Bachelor of Science degree 
from a recognized engineering school. 
Concentration should be on applied en- 
gineering courses rather than the more 
theoretical subjects. A Master*s degree is just 
as desirable here as in other engineering jobs. 
It is especially important if you later decide 
to change to '^in-plant*' work- 
Requirements for field service technicians 
vary between companies. In general, the 
higher quality organizations require two 
years of junior coUege electronics, a 
technical school certificate^ or advanced 
military electronics training. 

Completion of military service is 
advisable for all field service positions as this 
provides invaluable experience in working 
with military personnel, and most field 
service organizations deal directly with the 
military. In addition, most companies pay a 
premium to men who have received training 
in armed services schools on equipment 
related to their products. 

The current demand is greatest for 
personnel with backgrounds in telemetry 
systems and metric radar, particularly those 
with experience In the uhf range. This is due 
to the big change in telemetry frequencies 
from the old 215 - 265 mhz band to the 
1435-1540 mhz and 2200-2300 mhz 
bands. Other critical areas are radar repair 
and digital data systems- 
Field service work may be any where in 
the world. As an example lEC, the prime 



124 



73 MAGAZINE 






FA A Field Service Techn^cfans aligning 
UHF receiver banks. In addttion to on-the- 
job training, the FAA provides exceMent 
classroonn instruction at the FAA Academy. 

contractor fox POLARFS/POSEIDON test 
instrumentation has operations in Spain, 
England J Guam and at shipyards in the U. S. 
In addition, they supply personnel and 
equipment for special operations on ships 
throughout the world. Men in organizations 
of this type learn to move fast. Frequently 
they have to be at a new location thousands 
of miles away overnight. This type of work 
demands the development of tremendous 
versatility. One job may be trouble shooting 
the latest S-band telemetry system on a 
tracking ship, the next may be installing 
missile test equipment on a nuclear sub- 
marine. 

A well-known field service organization is 
PhUco-Ford's Educational and Technical 
Service Division* This organization grew out 
of the famous **Tech'Rep" group. They 
currently have operations throughout the 
world, from exotic pacific islands to Viet 
Nam, The services range from operating 
missile test ranges to running mess haUs! 

How do you find out about job openings 
in field service? Probably your best source of 
information is the Sunday edition of the Los 
Angeles Times. Other sources are the trade 
journals such as the IEEE Spectrum and the 
Engineering Opportunities magazine- 
Remember, most big electronic companies 
have field service divisions. A letter to their 
personnel offices will usually bring you a list 
of their openings. 

There is a wide range in the quality of 
field service organizations. Some are little 



better than hiring halls for semi-skilled 
technical personnel- Others provide men 
capable of doing advanced engineering. It 
pays to carefully investigate before accepting 
employment. The company^s name isn*t 
always indicative of the quality of their field 
service branch. Arrange to talk withr per- 
sonnel working in the organization, and visit 
one of their facilities, if at aU possible. In 
general, the smaller the company the greater 
the variety of work available - and the 
greater the individuafs responsibility. 

There are many ''pros and cons" to field 
service jobs. In the asset column you have 
travel, adventure, the challenge of working 
on a wide variety of state of the art 
electronic equipment, working with inter- 
esting people and high pay. On the hability 
side you have extensive travel, complicating 
your family Ufe, high living costs, wierd 
climactic conditions, and high pressure 
work. If you are looking for adventure and 
are single, the habilities are quickly over- 
come! The pay, which is above average, 
helps, and in most instances there is an 
additional tax free per diem allowance of 
from $12 to $25 per day, 

. . , W6JTT 



au^ 



OFFERS 



FROfA 
STOCK 

A COMPLETE LINE OF 

nr- 

VERTICAL ANTENNAS 

MODEL IBAVQ . . . A highperfor- 
mor»ce all-band vei-tical* Autornatk 
bond switching oll-bondi 10 thru 80 

meters. Feotar«s irvdi vidua] Jy tun«d 
Hy*Q trops that provide peobced 
performance on each band. Takei 
maximum legal power. Feeds with 
52 ohm coax. SWR less than ?:1 
on all bands. Simple to instoll on 
ground or rooftop. Withstands 100 
MFH winds when properly guyed, 

Modef 1BAVQ'U7.5Q NET 

OTHER MODEL VERTICALS 
IN STOCK. 

14AVQ 10 thru 40 Meters S35.95 
12AVQ 10, 15 & 20 Meters $26,95 

ALSO CHECK WITH US FOR OTHER 
HYGAIN PRODUCTS, 



18AVQ 





i 




OCTOBER 1969 



125 



-1 



continued from page 7 

agers, I frequently find that they have no 
desire at all to make money. This may be 
apathy or it may be a reaction to parents 
that idolized money. It is frustrating though 
to have wliat seems to me to be a really 
simple way to almost unfailingly make a 
fortune and find that no one is listening. 

How long do you think it will really be 
until we have space stations parked in our 
skies making wires across the earth a thing of 
the past? Telephones in the shirt pocket. FM 
radio and TV from space. Instant accounting 
down to the smallest store in the country. 
Letters and photo copies anywhere instant- 
ly. The hardware and software for this boom 
will be manufactured by new companies, 
and hams will play an important part. The 
youngsters that recognize this now and get 
ready for it wiU be the winners. Ham radio is 
an excellent start. And courses such as 
advertised by Cleveland Institute can*t but 
help* 

It might be inspirational for the younger 
members of your radio club if you invited 
some of the older members who have used 
their background in ham radio and parlayed 
it into success to give a talk. If you don*t 
have any real success stories in your club^ 
look around your local area and you'll find 
them. 

Much of the hard work they will tell you 
about and which is a key ingredient of their 
success, is education. It may not be in 
college, but it could be self-education^ read- 
ing, mail study courses, and brain-picking 
every expert you can corner. 

Before you sit down to write a heated 
letter hating me for discussing such out- 
rageous ideas, please take some time and 
marshal your facts, I will bow to documen- 
tation and facts, not to steam and emotion 
based upon disturbed beliefs. As always, 1 
will most enthusiastically publish further 
thoughts along this line, pro or con. 

Reactionaries 

The next time you run into someone on 
the air or at a club meeting that gets mad 
when you try and discuss methods of im- 
proving the ARRL, just remember that 
reaction is a very normal human condition. 
The human body tends to reject the trans- 



plant of foreign tissue on it. This certainly is 
rather parallel to the way in which any mind 
tends to reject any idea which seems un- 
fa miliar or wliich threatens an existing 
system. The intrusive forces are sloughed off 
or ignored, just as an aging Hon tamer resists 
the decision of a circus manager to buy more 
lions, or just as an executive tends to resist 
the decision to computerize a business, 
forcing him to grow into new skills. 

Ideas must be presented slowly and 
cautiously, always equating them to pre- 
viously understood concepts, if they are to 
be accepted. It is all too easy to leap into a 
conversation, as I frequently do, presenting 
the solutions to problems rather than the 
groundwork for understanding the problems, 
which wlU in turn lead to the obviousness of 

the solutions. Don't do as I do, do as I say: 

Marathon Nets 

Bud Massa W5VSR has been registering 

some legitimate complaints about the over- 
bearing arrogance of some net control opera- 
tors. His letters are inflammatory, so Til 
digest the complaint for you. The problem is 
that some net managers have gotten the idea 
somewhere that the net frequency is sacro- 
sanct and that everyone should move off the 
frequency when it comes net time. After 
using a certain frequency for some months 
or years they have developed the strong 
belief that this is now their frequency. 

As a strong believer in the value of nets, I 
recognize that they serve several very useful 
functions. First of ail, by making it conven- 
ient for a group of similarly interested 
operators to get together they make amateur 
radio more fun for all involved. I'm all for 
tills. Secondly, by stacking a large number of 
stations all on one frequency with, normally, 
only one talking at a time, gjeat gobs of 
frequencies that might otherwise be used are 
conserved- I'm all for that, too. 

There is no question that it is a lot more 
difficult to run a floating net than a fixed 
one. When the qrm is heavy, it can be 
awfully hard to locate a net if it is even a 
khz off its regular channel. Most of the time^ 
tliis really isn't true, and the gathering could 
easily take place plus or minus 5 khz with 
little difficulty. 

Perhaps a Uttle more consideration from 
everyone concerned will smooth over the 



126 



73 MAGAZINE 



p 



problem before it gets to the FCC petition 
stage. Net managers could make a try at 
starting on the net frequency and, if resist- 
ance develops, could ask the fellows using 
the channel to direct net call-ins up or down 
a few khz to a clearer channel. Four years 
ago I was given the stiff arm by the net 
control of the YLRL net and I am still 
resentful. Let*s try real hard not to have this 

continue, 

FCC Actions 
RM-1455 is a request for the FCC to 

return to its previous practice of issuing 
requested amateur radio calls, when avail- 
able, when sufficient reason exists for their 
issuance. It proposes that similar calls be 
issued to amateurs changing call areas. Thus 
WIXYZ could request and receive W2XYZ, 
if available, upon moving to the second call 
area. 

With roughly one fifth of the amateurs 
moving every year^ it would be nice if we 
could return to the old FCC custom of 
permitting the retention of the call suffix 
when changing call areas. Please drop a letter 
to the FCC backing this proposal so we can 
maintain our call letter individualities. 

RM-1456 is a request for the Technician 
licensees to be granted the same A-1 oper- 
a ting privileges as the Novice Licensees. 
Since the only difference between the 
Technician and the Novice License is the 
theory exam, there would seem to be as 
much value in the Tech having the same 
opportunity to learn CW by practice on the 
air as the Novice. Since few VHF receivers 
are capable of receiving CW, the Techs are 
robbed of the use of code* We might see 
many more of them going to the General 
Qass License if they were not bottled up on 
voice bands. 

Please write to the FCC and give them 
your thoughts on this matter, FCC, Washing- 
ton, D.C. 20554- Only one copy is required 

for comments on RM's. 
FCC Pronouncement 

Since the fall amateur contest activity will soon 

be here J we believe you will be interested in a 
resume of a recent explanation of what the 
Commission considers to be an acceptable station 
identification, as follows: 

For comphance with rule Section 97.87(a), the 
last transmission of the exchange of transmissions 
with another station must include that "other" 
station's call sign- For example "BK 589 CAL TU 



DXIDX de W6XYZ K" would be in compliance 
with §97 •87(a). When there is a need for identifi- 
cation of the "other" station in an exchange for 
the benefit of our monitoring facilities, it is most 
likely to be heard if it is in the last transmission or 
at the end of a long single transmission. 

Where the transmissions of an exchange are 
very brief, such as the typical contest exchange, if 
it is less than 30 seconds duration, the entire last 
transmission is considered the '*end of the ex- 
change" for the purpose of compliance with 
§97. 87(a)* Provided there is no mistaking which is 
the transmitting station's call sign, the call signs 
may be anywhere in such last transmission. While 
the rule no longer gives examples, continuation of 
the traditional practice of placing the transmitting 
station's call sign last or preceding it by "de'* is 
acceptable for this purpose. 

Examples of acceptable end-of~exchange trans- 
missions of less than 30 seconds are: 

^^DXIDX de W6XYZ 589 CAL BK" 

"DXIDX W6XYZ 589 CAL K'* 

*'DX1DX 589 CAL de \V6XYZ r* 

*'DX1DX 589 CAL W6XYZ K'' 

'^589 CAL DXIDX W6XYZ K" 
For telephony, the voice equivalent of the fore- 
going examples may be used, substituting ''this is" 
or "from" for "de", etc, 

ARRL Questionnaire 

Some $37,000 has been quietly spent by 

the League General Manager out of a fund 
set aside several years ago for the inter- 
national protection of amateur radio. Are 
the members of the League entitled to any 
accounting of this substantial expenditure? 
Usually reliable sources-tell us that a good 
part of these funds have been used for 
pleasure junkets for top HQ officials. Who is 
responsible for accounting for these funds? 
Has there been any evaluation of the inter- 
national status of amateur radio or of the 
effect that the spending of this $37,000 has 
had? When something like this is kept a tight 
secret it is only natural to worry that there 
may be a cover-up of skullduggery. 

The stockholders of most corporations 
insist on knowing where the money goes. 
They demand to know the salaries of the 
officers and want nothing hidden from them 
in the published financial statements. ARRL 
members have, for many years, been asking 
for the same basic information about their 
club, but with no success whatever: The 
truly impressive salaries at HQ are highly 
classified and subject only to conjecture, 
even by staff members* If the salaries axe 
reasonable, then why this tight secrecy? 
What is being hidden? Wayne 



OCTOBER 1969 



127 



ZL to SM Moonbounce 

John ZLIAZR arranged schedules with 
Kjell SM7BAE during early 1969, but the 
very short overlap of mutual moon visibility 
made it difficult. Times and frequencies 
were worked out, with 144.003 mhz being 
selected. The antenna would have to be 
pointed witMn 2^of the moon. "On our first 
sked on March 3rd we heard each other at a 
just detectable level. The next day, at 1728 
GMT, call signs were partially copied and at 
1746 signals peaked to 12-15 db above the 
noise. In the next few minutes call signs and 
signal reports were exchanged to comply 
with the accepted standards required to 
constitute an official contact. 

"The total useful period was about eight 
minutes, the moon's elevation was 9^ and we 
think that the extra 3-6 db ground reflection 
gain due to low angle radiation greatly 
assisted/' 

SM7BAE ran 1500 w to a 4CX250R and 
16 ten element yagis. The receiver used a 
2N4416 preamp up at the antenna, ZLIAZR 
ran a pair of 4-40 O's in Class B with about 
600 watts output and eight bays of 6/6 slot 
fed yagis. The receiver had a preamp up at 
the antenna, and a bandwidth of some 200 
cycles* 

The signal report system used was a code 
containing the letters T, M and O, T means 
that weak signals are present, M means that 
partial call signs are being copied. O means 
that both the call signs and signal report 
have been copied* If almost perfect copy is 
possible the number ''5" is used. Dots are 
hardest to copy, so dots are only used in the 
signal reports when good copy is probable. A 
contact may be claimed if an O level is 
achieved. 

The distance involved was 1 1 ,370 miles, a 
Uttle better than Ray VK3ATN's 10,417 
miles, 

John tells us, **There is no easy way with 
moonbounce. Anyone deciding to have a try 
must be prepared to stop being a communi- 
cator and become an experimenter/' 

The above information is from the Journal of 
the Aukland VHF Group^ via Amateur Radio, the 
Jownal of the WireleBs Institute of Australia, 



Boy Scout Jamboree-On-The-Air 

October 18-19 

Held since 1958, the Jamboree-On-The- 
Air (JOTA) has become one of the most 
popular events on the annual scouting calen- 
dar. Like scouting itself, the JOTA has 
grown from what in 1958 was just an idea in 
the head of Les Mitchell G3BHK to an event 
which every year attracts some 3000 stations 
in over 70 countries, each with its own little 
group of Scouts, Cubs and Guides. Some 
stations have as many as 150 Scouts atten- 
ding during the 48 hour event. 

Apart from its main object in promoting 
friendship between the boys, the JOTA does 
have one" other major aim— that of intro- 
ducing boys to amateur radio. It is interest- 
ing to find that several hundred bOys have 
ob tamed their own amateur licenses as a 
direct result of being exposed to our hobby 
for the first time during the JOTA. Some of 
them are known to have gone on and made 
their careers in electronics and allied fields. 

On a world wide basis the JOTA is 
organized by the Boy Scouts World Bureau 
which was untU early 1969 located in 
Ottawa, and whose permanent station 
VE3WSB became a most sought after stat- 
ion, not only during the annual week-end of 
the event, but also during Jamborees, Ex- 
hibitions, etc., to which it was transferred by 
special arrangement. 

In May 1968 the World Bureau was 
transferred to Geneva, While awaiting the 
completion of their permanent homCj the 
directors have gratefully accepted the offer 
of the use of 4U1ITU for the 1969 JOTA, 

Thanks to the Bulletin of the Swiss Union of Short 
Wave Amateurs for the above. 




If 



Up with miniskirts!" 



Moving? Please 
Let Us Know! 



128 



73 MAGAZINE 




Scan 



nin 




the Flyers 



Cart Drumeiler WSJ J 
5524 NW 5Sth Street 
Oklahoma City, OK 73122 



I Scanning H & R/s Catalog 35 

I Herbach and Rademan catalog volume 
35, number 3 hardly can be classified as a 
"bargain sheet"' in the usual sense of the 
term. It does, however, provide the widest 
selection of high-quality electronic and 

I mechanical gear you can find anywhere . • , 
and often at much reduced prices. As cus- 
tomary, this catalog leans heavily toward 
laboratory-grade goods. Some of the items 
are used, but all are in top-class condition. 
Meter multiplying resistors, at 0.5% accuracy 
and standard capacitors at 0,5% accuracy are 
examples of components. There is page after 
page of General Radio, Hewlett-Packard, 
Tektronix, and other laboralory-type equip- 

F ment. These are not cheap. For the amateur 
constructor, tliere's a 0-400 microam meter 
with a needle movement from right to left 
. . . just the item for a signal-strength meter 
in the plale circuit of a tube. Another choice 
article is a miniature 200-0-200 microampere 
meter, zero center, that mounts with a single 

t'A-inch panel hole. This should be handy for 
a discriminator or a phase meter. The first- 
listed is priced at $3.00, the other at $2.00, 
For a permanent shop set-up you can buy 
(for $15.00), mounted on a black anodized 
aluminum panel, 2-inch Weston meters: O-I 
ma dc, 0-5 kv dc, 0-500 v dc, 0-20-100 ma 
dc, 0-1 50 V a c. If you're interested in stable 
frequency standards, how does this strike 
you? A 500 khz crystal oscillator with a 
two-stage harmonic amplifier for S5.00; the 
crystal is in an oven which requires 6,3 v at 1 
a; the oscUlator and its amplifier need 105 v 
at 10 ma. 

Scanning tlie Radio Shack No. 189 Flyer 



I 



A new bargain llyer always makes 
interesting scanning. This one is no 
exception. Several unusual ''buys'' catch 
your eyes immediately. Like, for instance, 
lO-watl resistors in fractional- and low-ohm 
values such as are needed for power 



transistor emitters: these are two for 79^. 
Their aluminum ^*mini'^ boxes are both 
inexpensive (H^)4 to $L29) and adaptable to 
many a hamshack project. 

It seems that most projects involve 
transistors. And transistors often are happier 
if you use a heat-sink when soldering to their 
leads. At 99^ for a kit of five, you can buy 
peace of mind inexpensively, especially 
when you consider that one of the five has a 
magnetic base that'll often provide that third 
hand which nature failed to provide to 
electronic experimenters. 

Although the designers probably didn't 
have amateur radio in mind, the "Servo- 
Switch" ($14,95) can be used to good effect 
by many operators. It comes in two units, 
both of which plug into the AC power line. 
One unit, the receiver^ sets adjacent to the 
device you want to turn on. The other is a 
transmitter that you can take into any other 
pyrt of the house. If you want to watch a 
TV program right up to the minute you're 
due on a schedule, you watch it. But, about 
ten minutes before "air time/' you snap a 
switch on that little hand-held transmitter 
. , . and on comes your rig. 

The 69^ packets of small hardware are 
hard to pass up. It seems that youVe always 
short of some small item. With 28 to choose 
among, most of your needs can be met. 

Scanning World Radio Lab's Catalog 

This catalog is unique in at least one 
respect: It is the only one that starts out 
with amateur radio gear and then drifts into 
CB and audio equipment! And what a 
welcome relief it is. 

In another matter, too, it is higlily unu- 
sual. That relates to the wide variety of 
amateur equipment lines it lists. You might 
think Leo would push his own excellent line 
(Galaxy) to the exclusion of others. Not so- 
You'll find Swan, Drake, Sideband Engi- 
neers, Jolinson, Ameco, Gonset, Millen, 



I 



^ 



OCTOBER 1969 



12!? 



Waters J HaUicrafters, Collins, National, Ham- 
mar] und, Sonar, and a few other but lesser- 
-known brands given quite complete cover- 
age. The prices are right, too. Like many 
other dealers, you'll find ''discounts" (a very 
naughty word among manufacturers and 
many dealers) hidden under the guise of 
inflated "trade-in" allowances. These, of 
course, apply only in instances of purchases 
of higher-priced items. Most dealers consider 
themselves fortunate if they don't have to 
pay too much to have traded-in equipment 
hauled off to the city dump; so they can 
take this loss only when there's a consider- 
able profit on the sale. 

This catalog lists quite a number of items 
that you can't find easily elsewhere- Open- 
wire transmission lines, copperweld antenna 
wire, guy wire, three-gang capacitors for 
pi-networks, coils and switches for pi-net- 
workSj and (hold your hats!) ferrite beads! 
Another item seldom seen is a miniature 
rotary switch that has a progressive shorting 
feature , , , a very desirable capability in 
some applications. Another rare one is an 
adapter to mate a male uhf connector to a 
female Type N connector; this for just 

From the stand-pomt of a really complete 
listing of manufactured amateur trans- 
mitters, transceivers^ and receivers, plus a 
reasonably good listing of components for 
amateur building projects; I conclude that 
the World Radio Laboratories catalog is one 
of the most valuable available. 

Scanning the Poly Paks Flyer 

Bargain hunters are getting a glassy look 

in their eyes - . , that new Poly Paks catalog 

has just too many attractive "buys" to keep 

track of them. You can pass over page one, 

>ut page two lists a 1 .5 A, 2000 PIV diode 

or just $1.00; it ought to hold just about 

my power supply for modern transceivers, 

'age four shows a Fairchild 703 linear 

ntegrated amplifier for $1,59. That's hard 

o beat. Across on page five, you'll see a 23 

/ NPN transistor, rated to 400 mhz, for 

2.99. At that amount, one can afford to 

idulge in frankly experimental '"cut and 

ry" exploration in the field of transistorized 

ransmitters. Page six is a happy hunting 

round. There you'll find 15-olim earphones 



at 4 for SI -00; SOOO-ohm ones at 2 for 
$L00. Handsome instrument knobs are 5 for 
$1.00 in the 2'* size and 3 for $K00 in the 
3" .size. These are for !4" shafts. The back 
cover, reaUy page eight, shows 2N2222 NPN 
transistors at 5 for $L00, Considering that 
these are good for a half -watt dissipation, 
can stand up to 60 volts or take up to 800 
ma (but not both at once), and work 
satisfactorily art 250 mhz; yoi^'d be hard put 
to come up with a better source of oscilla- 
tor, multiplier, and buffer stage transistors. 

Scanning the Allied Summer Flyer 

Like many flyers, tliis one tends more 
toward completed items of consumer's 
goods rather than components. Nevertheless, 
it's of interest to the avid bargain hunter. 
Leafing tlirough it, the first thing to perk 
your interest may be tlie $10 price reduction 
of the Model A-2515 solid-state 
communications receiver, which makes it an 
even more desirable item to have around to 
supplement your amateur-bands-only 
receiver. Overleaf is an i^M-FM receiver for 
$8-88, This triggers a thought: Why not a 
converter feeding into this for a nearly 
no-cost 50 mhz or 144 mhz FM receiver? 
(More on tliis later,) 

Now for some components. Twelve heat 
sinks for popular-size transistors for just 
$1.78 looks like a real bargain. So does a 
transformer having 6.3-V and 65-V (center 
tapped) secondaries for only 9%4\ this Is 
nearly .ideal for transistor experimentation. 
A wide range of zener dioded at two for 68^ 
(1 to 2 W rating) suggests inexpensive 
voltage regulation for tbat power supply. 
And there*s a crystal microphone for %%i\ 
Remember what they used to cost 30 years 
ago? 

Let^s get back to that converter-plus-FM 
receiver combination. This begins to look 
even more interesting when you read over 
the specifications for the $29,95 Model 
KG -2 20 receiver kit. This has all the goodies 
that would cost you time, effort, and money 
if you were to build your FM receiver from 
scratch- Ft has a ratio discriminator (none of 
this slope-detection makeshift), squelch, and 
slow-motion tuning. Its metal cabinet should 
provide some measure of sliielding, if you 
were to use it as a tunable if. Having both 



30 



73 MAGAZINE 




r 



tubes and transistors, you*d have power 
available for either type of converter. 

A simple crystal-controlled converter for 
either 50 mhz or 144 nihz should be easy to 
design and construct. For local signals, one 
dual-purpose tube would do the job. Or, if 
you're really ambitious, you could come up 
with a converter that would break the 
squelch on a one-microvolt signal! 

Scanning the Olson #769 Catalog 

Olson is a firm that issues catalogs at 
rather frequent intervals; therefore each edit- 
ion differs but little from the previous one. 
Catalog #769 lists the usual lines of imports, 
mostly useful gadgets, but few items relating 
directly to amateur radio. Of course, cr>^stal 
microphones at two for one dollar will 
attract the attention of any amateur who 
works phone. And if that amateur has a 
phone transmitter without VOX, he may be 
interested in spending $14,95 for a hand- 
held microphone with a built-in six-transis- 
tor VOX circuit. As no anti-VOX is provi- 
ded, he may have to keep his receiver 
volume low or wear headphones to avoid 
chattering. Another useful item is a circuit 
breaker that may be used on everything 
from low-voltage dc to 117-volt 60-Hz ac. 
These may be had for 1, 5, 8 or 20 A at 
prices ranging from $2.99 to S3.49. 

. , , W5JJ 



Errata 



'^:C 



T . s-i; 



BUFFER 



_A_ 



\ 




t 



-O +Sv 



03 



1 

OZ ! 

2M2907 I 



tOOK 





IN645 



tu .T^C 




^SlNE WAVE 
OUTPUT 



ev 



r 



GND 



This was left out of the article on page 88 
of September- Please cut it out and stick 

it in. 



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1 




OCTOBER 1969 



131 



i^ 



m^m 



Houtf) jTorum 



Ralph Irace WAIGEK 
Assistant Editor , 73 
Peterborough, NH 03^8 



Today's youth has been speaking out all 
over the world as it has never before in 
history. The protests are heard in colleges 
and even high schools. The pressure is 
building up and perhaps we can look 
forward to some explosions in amateur 
radio • 

Youth has been getting the dirty end of 
the stick from the ruling cliques in many 
amateur radio clubs. In others, and more 
usually, they drop out in disgust. Bad scene 
either way. 

The rumble of discontent has been rising 
steadily at ARRL conventions and the day 
may not be far away when something 
breaks. The youth are well aware of the 
dirty deal they have been getting from the 
entrenched old timers who are running the 
League. They've watched the ARRL Incen- 
tive Licensing scheme eat dangerously into 
the ranks of the youngsters and they are 
angry over the new two year wait for a 
higher class license. They've watched the 
FCC figures showing a catastrophic drop in 
newcomers to our hobby and they point an 
accusing finger at ARRL HQ, 

The rigged ARRL Open Forums at 
conventions are no longer fobling the 
youngsters. They want answers. They want 
action. They want a change in the basic 
ARRL policies which prevent a Novice or 
Technician from holding office. They are 
bitter over the recent change in the by-laws, 
obviously aimed at them, where the 
Directors explicity prohibited anyone under 
21 from running for the office. 




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Have you run into an SCM that refuses to 
appoint teenage liams to leadership posts 
(EC, SEC, etc.)? If you run into this, and it 
is not unusual, unfortunately, then get 
together with some friends and try and get 
the rascal out of office* Let him know that 
you care. If you round up the teenage votes 
you could well win, because many of the 
older hams are, sunk into disinterest and 
could caie less even if the hobby continues. 
They may be dead from the neck up, but 
you aren't and you can run rings around 
them. 

Teenage traffic nets are fun and informa- 
tive. They are a step in the right direction. 
There are only a handful at the moment, 
such as the New England Teenage Net which 
meets daily on 3905 at 1900 EDT, The 
Missouri Teenage Traffic Net meets Monday 
through Saturdays on 3904 at 1900 CST, 
The Cornhuskers (Nebraska) Teenage Traffic 
Net gets together daMy on 3982 at 1830 
MST, The Tennessee Teenage AM Net works 
Monday, Wednesday and Fridays on 7280 at 
2200 EDT, If you know of more nets please 
tell me about them* 

We really do need a lot more teenage 
nets, so how about getting things started in 
your area and passing along the word to me? 
We could even use a national teenage net if 
some of you want to bite off a really big 
chunk to chew on. Sound groovy? Ahright, 
write to me. 

In the meanwhile, how about making a 
big try at getting some teenagers into the 
SCM chairs. Do you realize that not one 
single SCM in the entire 74 ARRL sections is 
a teenager? It is really about time that the 
teenagers got into gear. It takes only five 
signatures from ARRL members to run for 
SCM, you know. Don't let them keep you 
down forever , . , give them a battle this 
year! 

...WAIGEK 



^ 



132 



73 MAGAZINE 





DUAL TRANSISTOR IGNITION SYSTEM 



f 



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Mw f4iM« *t»m* 




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with chamois-type covering, metaf headband, cord 
and plug. 4 to 16 ohm impedance for use with 
any radio or TV, etc., by attaching to the speak- 
er leads. May be converted to "stereo" by 
making connections at each ear phone. This is 
a real bargain for quality RCAF head sets. 

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OCTOBER 1969 



133 



LETTERS 



bear Wayne, 

I believe your honorable draftsman made a 
small erroT in the ^*u!tra stable power supply" 
diagram on page 116. The IK resistor ought to be 
in the '*down" lead from the +300 volts; the low 
voltage end of the IK then goes to solid-state VR 
and to plate of Vl-B. 

Neil Johnson W20LU 

74 Pine Tree Lane 

Tappan, NY 10983 

Dear Wayne, 

^"The Genesis of Radio Reception" by WIUSM 
in Aug. 73 was most interesting, as it contained the 
technical information on early radio expeiiments 
that history books always leave out. 

Bill Hood's excellently written article, however, 
makes no mention of the American, Nathan 
Stubblefield, who is certahily not an unknown. On 
the contrary, Stubbleficld must be rated as the 
most inventive and advanced of the radio pioneers. 
In 1892, he demonstrated his apparatus which 
could send and receive voices and music at 
distances of at least a mile over land or sea. He 
even built smalU portable rigs that equalled or 
bettered the performance of today's economic 
marvel of Japanese technology -the three transistor 
walkie talkie! 

This, mind you, was happening several years 
before Brardy learned how to make iron filings 
fidget in his '*coherer,** many years before the 
electron tube or thej:rystal diode, and quite a 
while before the eighteen year old Marconi would 
become famous with his crude spark-gaps and 
"conveyor-belt" receivers. 

I would certainly like to see some information 
on the circuits and equipment used by Nathan 
Stubbleficld, the apparently forgotten inventor of 
modern radio communication, 

J, R. Johnson WA5R0N 
5111 Boca Raton 
Dallas, TX 75229 

Dear Wayne^ 

After reading your recent editorial about the 
ARRL proposing to give away ten meters to the 
CB gang I went on the air and tried to get some* 
letters going to the Directors. Out of 25 contacts 
only three said that they would write. The others 
said it sure was terrible, c u agn sn sk. 

Bussed Piatt WA9ZVD 

126 Laura Lane 

Thornton, IL 60476 

Dear Wayne, 

In reference to my letter published in the May 
issue, I would like to thank the many hams for 
their letters and cards. Everyone received was in 
accord with my remarks on the incentive licensing 
issue that was forced on us by the ARRL and the 
FCC 

As I continue to observe the results of this 
insidious incentive licensing rule I see how it will 
have continuing cumulative psychological effects 
that will be detrimentak 



Most hams that do get the Advanced and Extra 
Class fmd a coolness towards them when they 
begin to mention it over the air. The majority seem 
to feel-well so what, now stay in your exclusive 
part of the band and don't bother us, there is 
enough qrm around without your type. So I 
suggest to the amateurs that wish to waste their 
time and money taking tlie Advanced and Extra, 
keep quiet about it. Just remember the ham on the 
other end may feel as I do that you have let your 
fellow hams down- they are sitting this one out 
because they feel it is a stupid, senseless, 
undemocratic and unfair ruling that will^ if given 
enough time and is ignored by the majority of 
sensible thinking hams,, be rescinded as it was 
before for what it is -useless and a waste of our 
band allotment. 

I suggest hams contemplating Advanced and 
Extra give the above serious consideration. I would 
ratlier keep all my friends than be thought of as a 
superior big brain and resented. 

1 sometimes wonder if this was not instigated 
for the express purpose of reducing the ranks of 
the amateurs in the United States. Could this be 
the amateur pill? 

One of the truths of warfare is to divide and 
conquer. They have certainly divided the amateurs, 
scared off many a newcomer and disgusted many 
an old timer into hanging up Ms key. 

George Brook Taylor W4PZS 

1 133 S,W- Fifth Place 

Fort Lauderdale, FL 33312 

Wayne, 

This is just a letter from a member of the 
younger generation who feels that while everyone's 
telling everyone else to run a ham radio, he might 
as well throw in his two bits. 

The credit for my original interest in amateur 
radio goes to Walker Thompkins K6ATX. As a 
twelve year old in need of a book report 1 read his 
adventure story, "SOS at Midnight'' and got so 
excited about it that 1 read his other books, ' CQ 
Ghost Ship** and '*DX Means Danger/ of my own 
free will. After following the books* hero, Tommy 
Rockford (16 year old electronics genius, footbaU 
player^ detective, and superhero-K6ATX), 
through many exciting adventures, I had learned a 
lot about fiam radio and 1 was eager to become a 
ham. As IVe always thought that 1 was a normal 
twelve year old, I will surmise that other twelve 
year olds can be equally impressed with Tommy 
Rockford and ham radio. 

Attention hams and ham clubs! Be certain that 
K6ATX's books or books like them are in every 
grade school library. But-make sure that in every 
book is an insert giving names, addresses, and 
telephone numbers of amateurs in the area who are 
willing to help people get started, or willing to just 
show a wide-eyed youngster a ham shack. 1 could 
have become a ham five years ago when I read 
"SOS at Midnight/' but I didn't make myself 
known, and local hams didn't make themselves 
known. 

Duane McGuire 

933 Crescent St* 

Raymond, WA 98577 



*^ 



♦ ^j*t 



73 MAGAZINE 




I 
I 



Daar Wayne, 

This bait store is located about a mile north of 
HiUsboro, Ohio on state route 73, hence the name 
"73 Bait," Mr. D. L. Simpkins is the owner and has 
given permission for you to publish the picture if 
desired. 

We could have "doctored" it up a bit with 
someone posing with a 75S3 on the end of a line, 
but thought that tJiis was sufficient to get the idea 
across. 

Paul Terrell, MD W8NT2 

1440 N. High St. 

Hillsboro, OH 45133 

Dear Sirs: 

I noticed the two following errors in the 

printing of my article **4 Thirty Twoer" in the July 

issue of 73. In figure 3, the catliode pins (pins 6) of 

both Vj and V2 should be shown grounded. Also, 

the value (riot too important, however) of C7 

should be .001, and C2 and C3 should have a 

maximum value of 20 pf. While this may seem 

trivial^ I did receive a long distance phone call from 

another ham who wanted to know the capacitor*s 

values. His keen interest in beginning the project 

overwhehned me, since I hadn*t even received my 

copy of 73 through the mail yet! 

Larry Jack WA3AQS/KL7GLK 

3 Barry Ave. 

^ ,^, Annapolis, MD 21403 

Dear Wayne, 

Just happened to run across the article ("Kluge 
Tube") in the March, 1969, issue. As I (along 
with a few other hams) was deeply involved in the 
development and mass production of this tube 
during W1V2, perhaps I can shed some light on its 
characteristics and purpose. 

The VT-158 was the brain-child of Dr. (Major 
at that time) Harold Zahl of the Ft. Monmouth 
Signal Corps Laboratory. It is essentially a 304TL 
with increased filament power and temperature 
(for increased emission) and with rather limited 
life by ordinary standards. 

Although the internal tank circuits may look 
like they are intended for a frequency of lOOOmhz, 
the operating frequency was 600mhz. The dif- 
ference being due, of course, to the internal capaci* 
tances- Mu was^ like the 304TL, in the neighbor- 
hood of ten. Power output of the VT-158 was 
about 200 KW peak, at an input of approximately 
1 megawatt, peak. The efficiency wasn't too good, 
but considering high-power triodes at this frequen- 
cy, it wasn't too bad, either- Operation was at a 
plate voltage of approximately 20kv with 1 or 2 
microsecond pulses at a repetition rate of 240 



pulses per second. The pulse modulator was a 
rotary spark-gap network*dischaige device attached 
to the shaft of the gasoline-engine driven generator 
which provided power for the whole system. The 
audio output from this spark-gap outfit was deaf- 
ening, and security of the installation must have 
been negligible. 

The radar system employing this tube was, so 
we were told, part of the D-Day invasion appara- 
tus. Although 1 was never privileged to see the 
complete installation, it w^as reported to have been 
housed in a tent with center-pole mounted para- 
bola* Its mission was to detect low-flying and dive 
bombers* As I recall, the prime contractor for the 
system was W9ZN's Zenith Radio- 

R. L. Norton, W6CEM 

722 East Gutierrez St., P. O. Box 1469 

Santa Barbara, California 93102 

Gentlemen: 

Recently I've run into some "old timers" who 
would like to get back on the air. One of tlie things 
that seems to give them pause is the new termino- 
logy wMch pervades the ham magazines. Modern 
electronic magazines are written only for the 
*^in'Crowd" who have mastered the new abbrevia- 
tions that these magazines have foisted upon them. 
Perhaps 1 can be of assistance -= here is a list of these 
modem abbreviations, along with the translation of 
what they really mean: 
pf • . • not a sneaker -usually, '*mickey mice" 
/if . , . too small to measure, forget it 
cap , , , pronounced ''condenser'* 
hz , , . pronounced * 'cycles,** with one exception- 
some modernists claim that **hz" is pro- 
nounced "Hertz," but who ever heard of a 
"cycles antenna"? 
khz . . . pronounced "Kilocycles" 
ghz . • . this horrible-looking glitch is the excep- 
tion-say **kay-em-cee" 

ERP your rf ammeter reading times at least 50, 

PI , - , a magic number equal to (a) exactly 3 or» 
(b) exactly the square root of 10 depending 
upon the equation in w})ich it's used 
SWR 
VSWR , . . swer or viz war -this you ignore in 

quoting ERP -ignore it 
FCC . - , means the same old thing- this you can't 

ignore! 

Doug McGarrett WA2SAY 

28 Holbrook Road 

Centereach, U U, NY 11720 

ITEMS OF TRIVIA 

Page 123-124 of July issue appears to have 
diagrams reversed -right? When 1 took my 1st class 
telephone test almost fifteen years ago, one of the 
questions involved an FM discriminator and all I 
could remember was where it was grounded. Still 
remembering only that, the diagram totally con- 
fused me until the text tended to clear it up. 

Vm sure glad you stay away from space-filling 
chatter ("Operating News") as one of the other 
magazines uses, such as W6XXX bought a new call 
book, or WA3XXX put some new finals in his 
linear. Seriously, the Pickering Radio people have 
an excellent product in their code practice tape, 
and after seven weeks of intensive work^ I passed 




OCTOBER 1969 



135 




the FCC test. The Pickering tapes should receive 
enthusiastic endorsement. (WA6CPP passed his 
advanced exam . , . ) 

Paul Schuett WA6CPP 
14472 Davis Road 
LodJ, CA 95240 
Dear Wayne, 

I've been reading your 73 Magazine editorials; 
and I like your frankness and open-minded views, 
so I'm wTiting to express mine. 

Just a little background so we talk the same 
language. I've been interested in ham radio since I 
bought my first receiver in 1933 for $33.00. 
Twenty-seven years later I sold it for $30.00 to a 
young fellow trying to get his ticket, and it worked 
like new. 

Over the past years, Tve belonged to several 
radio clubs and have helped many a ham get his 
ticket and a TVI free rig on the air. Why not, ham 
radio has been and still should be the best hobby, 
and it is a good investment for our country. You'll 
notice I said has been and should be, 

I consider the years up until the early I960's 
the Golden Years of ham radio. Those were the 
days of home brew equipment and comradeship. 
Fifty or seventy-five miles was not even considered 
wiien it came to helping a fellow ham de-bug his 
rig. The accompUslunent and the feeling of pride 
one received when he heard "old Virg's" rig on the 
ail made ham radio have a meaning. To sit up half 
the night and work on a piece of equipment while 
ragchewing with a mobile or two that were 
following the local H. S, or college team bus home 
through a storm was just part of being a good ham. 
Integrity, responsibility, and justifiable pride were 
a part of the teaching to be a good ham that was 
given each new ham. He knew if he did not 
measure up he would be dropped. 

In the early 60's several things began that have 
changed the conditions and attitude of ham radio. 
The two major ones were the introduction and 
acceptance of CB radio and SSB ham radio. 
Progress is inevitable and new things will come out. 
To classify or not, CB or SSB as good or bad is not 
really the issue, as both have their good and bad 
points. To point out the real issues, 1 will give an 
example that happened to me. Many (too many) 
similar examples have happened since; and 1 got to 
thinking. 

After successfully building my own, mobile and 
home, AM & F M rigs and could use the home rig as 
a relay station, I figured F*d try SSB. Some surplus 
xtals and equipment and many moons later I had 
an excellent workable rig with a grounded grid 
(4-I625's parallel on 75 mtrs,) on the air, TR 
switch and alL My first contact (outside local) gave 
me a good report at first but when we exchanged 
Q-th equipment types he never came back. Later 
(several days) I heard him ragchewing with another 
station, and he said he was not about to talk to 
anyone who didn't have top line (no commercial 
names) equipment. If the sigs weren^'t coming in 
S-9+ he wouldn't even answer them. As 1 said, this 
happened so many limes to me that I began to say 
I had ''top line"" equipment. Then I really started 
thinking. Is this really ham radio? 

Where had my integrity and pride of accomp- 
lishment gone? This is not the ham radio for me. 
So projecting a long took far into the future ! 
could see only one workable plan to keep Iiam 
radio alive and with sometliing to look forward to. 
So I began to express myself at clubs and on the 



air. Several old timers were with me, but that was 
the support I got. 

About this time CB radio was blossoming and 
(even through 1968 this is still happening) young 
higli schoolers and the college set found they could 
get on tlie air for $40 to $100 mobile or fixed 
station and no code, not even an exam for a 
license; and they could yak away to anyone in the 
country. The cost of SSB equipment for a mobile 
rig is from S300 to $500 and if they get that kind 
of money they invest it in wheels, a bomb or some 
sort, and then maybe^ I say maybe, a CB rig, It'^s 
easier, costs less, and they have less restrictions* 
They can even get a 65 watt transmitter for around 
$50; so who needs ham radio? Facing this reality, 
how does one go about getting them interested in 
being a true ham. 

One young (H. S.) feUow purchased a SSB 
transceiver and before he had it paid for it was 
obsolete (pwr. & selectivity wise) and his trade-in 
would be a lot less than he had a right to expect so, 
he operated as is. Try selling ham radio to some of 
these youngsters and they may go so far as to 
invest in a novice Tx & Rx and for a short time 
they enjoy it; then they find the temptations and 
the going tough. They have invested in low power 
AM equipment and have a hard time selling \L 
They key up and get a 2 or 3 word per min, 
contact and then the return op comes back with 10 
or 15 w. p. m. and they get discouraged and start 
tuning up the bands; and soon they find the CBers 
are having a balL Knowing most of them^ he finds 
he can get a xtal and pur his rig on with the rest of 
them. Another ham lost. 

It's not hard to see today's problems, or mess, 
or hangups, or what ever you call them, they are 
real and definitely with us. So once again Til 
propose what I feel is a solution to our problems. I 
know ril get a lot of static but then I'm used to it 
by now* 

The main thing is to think for the good of ham 
radio and not for the good of oneself. 

With SSB and RTTY proven to be fast and 
superior to CW why not leave OV out of the 
picture (except as a rider). All hams should by 
exam prove they know theory and good opera- 
tional practices. AH hams should be general class 
and use any band but be restricted to 250 watts 
input or pep power. (No more spirating of power 
and price out of the reach of the junior and the 
overseas ops,) After 3 years of a general ticket and, 
the buUding of a complex workable piece of 
equipment plus an exam one could get an advanced 
ticket that would entitle him to put a kw on the air 
on any band. 

Area clubs who have at least one advanced 
ticket holder as an officer would and should be 
permitted to give the exams. They would also have 
the responsibility of updating the hams in their 
area and of policing (if I may use the word) the 
same. F or the ham to again be looked upon as 
anything but a nuisance he must accept the 
responsibility and let those who can perform be 
the liaison between the FCC and the ham. The 
local newspapers are supposed to be for the good 
of the people they serve, so, why not have local 
committees or representatives to approach the 
local hams and CBers who are directly violating the 
rules and privileges of the area and print their 
name, address, and call in the local paper for a 
week or so. If they don't conform tlien let the FCC 
designate the action to be taken. 

Active clubs with dues and a place to use 



136 



73 MAGAZINE 





modern equipment are a must as technology has 
adviiiiccd beyond the stage of each liam owning his 
own test equipment or of (m many cases) the ham 
even repairing his own equipment. If we don't pull 
together, we wUl be (as we are now) pulled apart. 
As the first part of tliis letter explained, hams 
had a sense of togetherness that comes by doing 
thing Ji togetlicr, especially workinq together. We 
can no longer push the "on'' switch of a higli 
priced piece of equipment and be just appliance 
operators- If all we put into ham radio is money, 1 

t don't think we can expect much out, I was always 
taught the things worthwhile in life came from the 
heart and only the heart. All else jusl comes and 
goes. 
So what say, feUows, lets put a little heart into 
ham radio and once again make it a worthwhile 
thing. 
^ Wayne, I know that you and the rest of the 
staff will kick this around. Hop in, the band is 
open, 

William A. Gardner W8EAU 
5704 Decker Road 
North Olmstead, OH 44070 
Dear Sir: 

Why doesn't your magazine run a series of 
articles on computer and binary logic as applied in 
Integrated Circuits. There axe very few hams tliat 
can boast even the slightest familiarity with com- 
puter logic and L C/s* It would be nice to have a 
series of educational articles of the same quality as 
the "Getting Your Advanced Class License" in the 
past and now the "Getting Your Extra Class 
License," Thank you, 1 got my Advanced License 
thanks to your study course. 

John C. Koning WB6VQE 

4680 Crest view Drive 

Norco, CA91760 

Sounds like a loser to ma; any other votes on this? 

* . - ed* 



Dear Wayne, 

Glad to report the acquisition of the "EXTRA" 
ticket recently! 

Biggest factor towards getting it was the great 
articles on obtaining the '^big" ticket* They are 
written so the "self-taught guy" can grasp it -no 
technical terms, (or at least very few) very expiana- 
I tory, and really "step by step.' Other magazines 
are great if you're in electronics, or have an E, E. 
degree J but as for me-i needed some '^plain ol 
language" descriptions! 

I found 'em in the articles and must say 
"thanks a lot" to the staffs effort, 

R.J- Renart WB2AUF 

1 1 7-09 9 Ave. 

College Point, L- L, NY 11356 

Dear Wayne, 

In August issue, page 98, on output section, on 
leads going to the meter, a diode was left out (any 
small diode) for the rf output meter- 

Thought Vd bring this to your attention before 
someone else did! 

Bill Estick, KOVQY 

2607 E. 13th 

Wichita, KA 67214 
Deaf Wayne, 

During the past many years 1 have enjoyed 
amateur radio to its fullest degree. I have met some 
of tlie tlnest persons in amateur radio -and a few 
of the others. The spirit of maxim and others has 
carried amateur radio for decades. Today we need 



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4 



1 



OCTOBER 1969 



137 



ARCTURUS 



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a regeneration and real vital vitamin shots to 
mamtain tlie privilege of amateur radio operation 
throughout the world. 

The value of your efforts in publishing the 
magazine '*73*' is of tremendous value in preserving 
amateur radio as a hobby and as a public service- 
Many of us are grateful to you and to your staff 
for a job well done-but one that must continue. 

John TracVf WIGH 

49 Broadway 

Taunton, MA 02780 

73 Editor, 

I wish to express my thanks and congratu- 
lations on such a fine Advanced study course. I at 
first tried to learn from another well known 
publication, which need not be mentioned, and did 
notliing but memorize the answers as you said 
would and did happen, I am now using your Extra 
study, but because of the asinine 2 year wait for so 
called experience is keeping me back anotlier year. 
Anyway thanks again for such an outstanding 
study* You should publish the courses under a 
different cover. 1 am sure you would have a great 
success with it. 

Robert McGwier, Jr. WB4HJN 

P. O- Box 565 
GFove Hill, AL 36451 
Good idea . . .ed* 

Dear Editors: 

Congratulations on your decision to cover allied 
fields with separate publications. While there are a 
great many hams who use CB radio (to good 
advantage), and many who follow the SWbroad- 
castSj they would do better advised to subscribe to 
magazines in their fecial interest, I do not wish to 
hunt through SWL or CB news to get at the Ham 
articles. And those with one of the other special 
interests should not be so burdened, 

I recently checked an issue of QST and found 
about one tliLrd of it of interest to me. There are a 
great many Hams who are interested in contest 
news, organizational matters and other items which 
do not appeal to me, 1 do think QST does a fine 
job of covering tliis wide area. They have, however, 
fallen victim to a common failing of such 
publications (yours excepted). The people who 
write about articles they would Uke to see, but 
never bother to write that letter. Since the desired 
articles are usually advanced engineering, the 
Editors get the erroneous impression that tlieir 
readers all want it. They forget that they must 
attract more readers^ and they necessarily will 
come from those just starting. 

Your study courses have been by far the best 
*'Self Help" courses I have seen. With the 
traditional Q & A approach, there is too much 
tendency on the part of the student to try to 
memorize, rather than fully understand. There will 
always be a demand for the "quick and easy" 
memory course. From this poup come our 
appliance operators, although many do go on to 
learn, and build. 

Lester Utch WB4HPB 

1248 Haven Dr. 

Birmingham, AL 35214 

Dear Mr. Green« 

Having been a charter member of your institute 
of amateur radio, and followed with enthusiasm 
the meteoric rise of 73 from its inception, this 
letter is addressed to you because it is felt that it 



^ 



1 



138 



73 MAGAZINE 



I 



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TOWER 




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Louis. 





from the all-new, still unpublished "FM Repeater 

Directory," which is updated continuously and 

published quarterly in FM Journal 

Ken Sessions K6MVH 

_ .., Editor, FM Journal 

Dear Wayne, 

Yes, quite a few of us are out here want to be 
able to use more, not less, frequencies. Opening 
3650-3700? Now that would be incentive and 
would give us all a lift. I know that my operating 
has dropped off, way off, since last November. I 
find myself squashed toward the high end of the 
band, hearing how great it is back on the low end 
where 1 operated for the past 19 years. Yes, open 
something new. It certainly would cut down the 
QRM. And what about this VHF beacon for 
WlAW? What good is that going to do me? We sure 
do need something to spark up amateur radio, but 
I don*t think the punishment we have been getting 
is the answer. 

John W4AEQ 



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J 



140 



73 MAGAZINE 



will, at least, receive some kind of consideration. 

The subject: the QRM problem and crowding 
on our phone bands. It is time we press for 
remedial action. Incentive licensing certainly did 
nothing for this problem. At the crux of the matter 
there seems to be a glaring inequity in the 
frequency allocation that confines the U. sL 
amateur to a portion of the phone band, wMle 
foreign stations have full freedom of the range, so 
to speak. 

Late callbook figures show the U. S. amateur 
total to be near 290,000. While foreign registra- 
tions, not including Russians, are near 137,000. If 
we are the greater in number, and confined to the 
area of the North American continent geographic- 
ally, why should we be penalized for our numbers? 
Why should special portions of the phone bands be 
pre-empted for foreign use? 

If you tune across the American portion of our 
plione bands on most any weekend, you'll find 
something that pretty well borders on bedlam. 
While tuning the foreign portion of the band, 
you*lI find vast empty spaces there. 

At the time these frequency allocations were 
made for our phone bands, our numbers were not 
such as to create any problem. Today ^ even with 
our sophisticated equipment^ the frequencies 
available are not adequate for the prevailing 
demands. 

For a long time that has been a rather taboo 
subject; however^ it's time to open up Pandora*s 
box and let the thing out for an airing. 

We^ll never get our share unless we're in there 
fighting for it. It's time now to pick up the cudgelj 
pen and microphone to join in a combined assault 
on an unfair, outmoded agreement's bailiwick. 

W, A.HanksWOKJ 
Tebbetts, MO 65080 

Dear Wayne, 

Congratulations on a beautiful issue (August 
1969). I particularly enjoyed your FM articles; the 
timeliness of 73 in covering the "in" aspects of our 
hobby never ceases to amaze me. You people 
always seem to be "right on top of it.*' 

Referring for a moment to the article^ 
"FM-Fun Maker": Lest 65,000 anxious amateurs 
run out quick and buy crystals and FM units based 
on the author's stated popular frequencies, I think 
it advisable to contradict one small point. The 
author says: 

National repeater frequencies are 52,80 in, 
52.72 out for six meters and 146.34 in, 146,76 out 
for two meters. 

Prospective FM operators should be advised 
that in the United States and Canada there are 106 
repeaters whose output is on 146.94 mhz. There 
are only 29 repeaters in these areas with output on 
146.76. For my money, 146,94 mhz could hardly 
be considered anything other than THE national 
repeater output frequency. Also^ 1 know of only 
two six -meter repeaters in the entire country with 
an output of 52.72, and one of them is keyed from 
two meters. But there are 18 with an output of 
52-525 mhz. 

Like many otlier FM'ers, the author of the 
above-referenced article obviously does not Uke 
repeater outputs on national simplex channels. But 
he can hardly change the facts by ignoring them. 

As a miscellaneous tidbit of nonessential 
information, there are 234 open-access repeaters in 
the U. S, and Canada. Nearly 200 of them are on 
two meters. All information given in this letter is 



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5881-3.25, WE-CV677 1000WATT TETRODE- 
5.95, EIMAC-MACHLETT VT-158 1200-3000 
WATT BOTTLE-READ MARCH 1969 ISSUE 73 

HOW GREAT THIS IS"$9,95 12V 20AMP DIODE 
POWER SUPPLY (LESS XFORMER)~4.95, RCA- 
6-12 VDC CONVERTER DEL. 20AMP-12.95 
IDEAL FOR VOLKSWAGEN. SEND FOR OUR 
LIST OF OVER 3000 TYPES OF AMERICAN, 
BRITISH AND EUROPEAN IMPORTED TUBES, 
[LARGEST STOCK OF XMITTING TUBES IN 
THE WORLD, SEND FOR OUR LARGE PARTS 
CATALOG (OUR PRICES ARE THE LOWEST IN 
THE USA). 

UNITED RADIO COMPANY 

56-A FERRY STREET 
NEWARK, NEW JERSEY D7105 



BACK ISSUE GUNSMOKE ! 

30^ count 'em 30, stupendous tremendous 
(more handbooks than magazines) fascinat- 
ing enormous devastating incredibly ener- 
vating back issues of 7 3 ,,*,., •...,.•. 

ONLY $5.00 

postpaid worldwide 




Yes,., yes.. .yes., .here is a 
flolden opportunrty to 
Blow your mind on 30 
back issues of 73. You 
send us $5 in negotiable 
securities, cash or check 
and we will send you an 
unbelievable miscellany 
of thirty different (ail 
different) back issues, 
alt from the 1960-1966 
era. These are all rare 
collectors items. Every 
one could likely be wo- 
rth a fortune to you. Who knows, you might 
even find a rare January 1961 in this pile! We 
don't even know what is m these packages. To 
keep costs down we have had these magazines 
packed tnto sloppy bundles by the Chimps 
from Benson's Wiid Animal Farm {nearby). 
Watch out for banana skins, —if you want 
specific issues of 73 they are available at the 
low low (high) price of $1 each. Unless we 
don't have them. In which case the price is 
higher. —How about sending a bundle to a DX 
friend? Back issues of 73 are worth their weight 
in unicorn dung in most countries. —Money 
received without a shipping address will be used 
for beer. 

73 Magazine Peterborough NH 03458 



OCTOBER 1969 



139 







Price — $2 per 25 words for non-commercial ^ds; 
$10 per 25 words for business ventures. No display 
ads or agency discount. Include your check with 
order. Deadline for ads is the Ist of the month two 
months prior to publication. For example: January 
Ist 15 the deadline for the March issue which will 
be mailed on the 10th of February. Type copy. 
Fhrase and punctuate exactly as you wish it to 
appear. No all-capital ads. We will be the judge of 
suitability of ads. Our responsibility for errors 
extends only to printing a correct ad in a later 
issue. We cannot check into each advertiser, so 
Caveat Emptor • - * 

FOR SALE: Old 73's complete sets: '64, '65, '67; 
nearly complete: '61, '63, '66, '68, Make offers* 
Paul Capitolo, W6RQG, 1735 LeRoy Ave., Ber- 
Ikeley, CA 94709 

3 PLASTIC HOLDERS will frame and protect 60 
cards, $1— or 10 holders $3. Prepaid & guaranteed. 
Patent 3309805. Tepabco, Box 198N, Gallatin, 
ITennessee 37066* 



RTTY GEAR FOR SALE* List issued monthly, 88 
or 44 MHy torroids 5 for $1,50 postpaid. Elliott 
Buchanan 8e Associates, Inc., 1067 Mandana Blvd., 
Oakland, California 94610, 

"TOWER HEADQUARTERSI" 11 Brands! Heights 

aluminum 35% off! Strato Crank-ups-low costi 
Rotors, antennas and gear discounts. Phone patch 
$1 1 .95. Catalog-20^ postage. Brownville Sales Co. 
Stanley. Wisconsin 54768. 

SELL: COLLINS KWS-1, Ser. 896, $640; 75A4, 
Ser. 5763. S420-or both for SI 025. I will ship. 
Lew Hindert, Rt. 4, Box 290, New Braunfels, 
Texas 78130. 

ON AIR NOW: Complete SSB xmitter-Apache 
plus SSB adaptor pfus mike. Mint cond. All new 
tubes. $150. J: F, Weatherly K1ZYQ, 473 Auburn, 
Newton, MA. 

JOB WANTED^ 15 years experience writing and 
teaching, 12 years writing in space program. Have 

first telegraph and phone licenses. Now in New 
England, but can relocate. Anyone need a good 
experienced writer? Box 0-1, c/o 73, Peter* 
borough, NH 03458. 

CHRISTIAN Ham Fellowship now organized for 
Christian hams to have fellowship, to do tract work 
among hams. Christian Hamm Callbook $1 donat- 
ion. Christian Ham Fellowship, Box 218, Holland, 
Michigan 49423, 

SWAP MEASUREMENTS Model 59 GDO, excel- 
lent with manual for Freq. meter TS-323 with data 
20-480 mhz. Gordon W2IVIPT, 25 Norma Ave,, 
Lincroft, NJ 07738, 

SASEAQUARTER coin bring GE QSLs 
P247-"73/' W2RUT, Box 275, Fair Haven, NY 
13064. 



SURPLUS PARTS 

Latching Relay - Potter fit Brumfreld KB, 3PDT. 
1 1 5 V. 60 start, 6 v 60 stop. The 2 relays can be 
separated, making a DPDT relay with 115 v, 
coil, & a SPOT with 6 v. coil. 5 amp contacts. 
$1 ,25 each, 6 for $6 00. 

POWER TRANSFORMER, 275 v. no ct, 150 
ma., 12 V. @ 2 amps 1 1 5 v. 60 pri, 2 3/4" x 4" 
X 3y/^ h. Shpg. wvt. 7 lbs, $1.75 each, 4 for 
S6.00, 

POWER TRANS., 3500-350 v @ 130 ma, 6.3 
V. @ 3.6 A,, 5 V. @ 3 A, IT 5/230 v. pri. Open 
frame with leads, Shpg wt. 7 fbs. $2.00. 
.5 mf 400 V, oil-filled capacitors, rectangular 
case, mil. spec. SI .00 per dozen. 
Loading capacitor, 5-sections, 400 pf per sec- 
tion, 3/8" shaft. Will load full power into 50 
ohms. $2.00 each. Adapter to !4" shaft. 25rf. 
Shpg. wt. 4 lbs. 

1-inch PM speakers. 5,4 ohms. A[so make 
good mike. American made. 75i each. 
Transistors: 2^1187, 2N13n, 2N586. 15^ 
each, 25 for $2.50. 

Command XMTR SPECIAL: BC-457, 4-5.3 
Mc, good for vfo or for parts. Fair corrd. Less 
tubes. Shpg. wt. 13 lbs. S3. 00 each, 6 for 
S15 00 

GUARANTEED USED HAM GEAR 

National ISJC-303 with calibrator. Mint. S200,00 



Mosley CM-1 receiver 

Surplus BC-348 wfth AC power. 

Galaxy V with AC supply. 

Heath DX-IOOXmtr. 

Globe Hybander VHF 62 Xmtr. 

Hammarlund HQ-140X receiver. 



S 80.00 
S 70.00 
$300,00 
$ 75-00 
$ 49,00 
S10Q 00 



Hammarlund HQ-145X receiver w/spkr $160.00 

JEFF-TRDNICS 

4252 Pearl Rd. CIvlnd.O. 44109 749-4237 



BRIGAR 

ELECTRONICS 

10 ALICE ST. BINGHAMPTON, INI.Y. 
13904, AC 607 723- 3111 

* COPPER CLAD PC BOARDS. 6" X 36" 

CC both sides $2.16, 6" X 9 3/4" CC 
both sides 60<!f, 7" X 11 3/4" C one 
side 84(^, 5" X IVi" CC both sides 40cf, 

* STUD MT SILICON RECTIFIERS 12 
amp, 50 PRV. pkg of 5 $1 .00 

* ELECTROLYTICCAPACITOR1250mfd 

ISOvdc. 2"X4y4" 50dea. 

* JUST BOUGHT OUT ORIGINAL CASE 

FOR CB RADIO. Includes mtg bracket 
for mobile use & slide-in chassis. Holes 
pre-punched for power transistor & pow- 
er cord. May be used for mobile power 
supplies, P.A. system or speaker box or 
many other uses. Size - 314" H X 7" W 
X 872" D. Weight 3 lbs. Original cost 
$9.95. Our price $1,95 

MIN ORDER $5.00 



il 



OCTOBER 1969 



141 



Send 254 for Catalog 69-2 

VARIABLE DISC 
TRIIVIMER 

Miniature ceramic variable 
trimmer capacitor. Piston type 
tuning, size ,375 diam, ,275 
deep. Printed circuit mount. 
Amateur net on this is SI. 68 
each. Our price only 25i each 
or 24 for $5,00, All are brand 
new. State size, may be as- 
sorted if you wish. 

#N300 2,5-11 pf 

#NPO 5.5'18pf 

#N650 9-35 pf 





$€,400.00 MEMORY DRUM 




Military surplus made by* HUGHES for the AF, 
Condition appears excellent due to being enclosed 
in air tight case with terminations on plug con- 
nections. 134 read/write heads, 12 heads phase 
adjustable timing. Integral drive motor 115 volts 
400 cycle. 



Shipping wt. 39 lbs. 



* • + t * 



.#DRUM $100,00 



INTEGRATED CIRCUrTS 












900 


Buffer 


$1 00 


910 


Dual 2-input NOR 


1.00 


2-903 


Duaf input gate 


1.00 


914 


Dual 2'input gate 


1.00 


914-925 


Dual 2-input gate dual 






expander 


1.00 


923 


JK flip flop 


1-00 


925 


Dual 2 -Input gate exp 


1.00 


946 


DTL 4 2 input N AND/NOR 






gate 


2/1.0O 




DTL Clocked flip flop 


2/1.00 


tlVIB 


Dual 4-input logic gat© 


2/1.00 


7M6 


6 NPN transistors in one 






package, gen use 


3/1.00 


12M2 


Diff Amp 


1.00 


711 


Dual Comp Amp 


2.00 



JOHN MESHNA JR. 

19 ALLERTON ST., LYNN, MASS. 01904 
P. O. BOX 62, E. LYNN, MASS. 01904 



MANUALS- TS323/UR, TS-173/UR, BC^38A, 
R-274/FRR, TS-186D/UP, SSB-100, LM, $5.00 
each. Hundreds of others. List 2Qi. S. Consalvo 
W3IHD, 4905 Roanne Drive, Washington, DC 
2002 1 . 

TEXOMA HAM A RAMA! The annual Texoma 
Hamarama will by held again Nov 15-16-17 at the 
beautiful Lake Texoma State Lodge. Plan a plea* 
sent weekend for all. Bring the family. Mail 
registration fee of $2 per person to: Texoma 
Hamarama, PO Box 246, Kingston, OK 73439. 



GREENE . , center dipote insulator with . 
. , without balun , . see September 73, page 41, 



or 



QSLS???? Largest variety samples 25£ Sackers, 
WBDED, Holland, Michigan 49423, 

WANTED MODEL 28KSR in good operating 
condition for $250.00. K. Schwieker K4KQR, 
1 124 Opelika Road, Auburn, AL 36830. 

HEATHKIT SB-110 and Power Supply HP'23- 
Like New-$270.00. Charles Kehter, 1067 Western 
Ave,, Green Bay, Wl 54303. 

SSTV MONITOR, 12 transistors, 5 tubes, 3RP7A 
CRT, Bud Portacab cabinet, tuning indicator, $190 
plus shipping costs, Cohen W4UMF, 6631 Wake- 
field Dr., Alexandria, VA 22307. 

COLLINS 75 A4, Serial 2530. Excellent condition. 
Best offer over $300.00. Paul Delaney WB6B0Q, 
1328 Calle Pimiento, Thousand Oaks, CA 91360. 

FOR SALE: HT-37-HT33A, 2000 watts, PEP, 
Original owner. Good condition. $250.00. Pickup 
only. Fred Fetherolf, phone 614-332-3421, Lauret- 
ville,OH 43135. 

ROCHESTER, N. Y. is again Hamfest, VHP meet 
and flea market headquarters for largest event in 
northeast. May 16, 1970. Write WNY Hamfest, 
Box 1388, Rochester, NY 14603. 

VHP ROUNDUP Syracuse vhf roundup Oct. 11, 
1969, Three Rivers Inn, Rte 57, 10 miles north 
Syracuse. Tickets, W2RHQ, 902 First North St., 
Syracuse, NY 13208, 

TELETYPE PICTURES FOR SALE. 50 pics for 
$1.00. Perforated and audio tapes available. Write 
for prices specifying speed and tracks. Pictures to 
be included in second volume solicit^. W9DGV, 
2210 30th St., Rock Island, I L 61201. 

WARREN COUNTY N. J. W2JT/2, October 18-19, 
3555, 7055, 14055, 21055, 28055, 3855, 7255, 
14255, 21355, 28555. QSL to W2 bureau, 

HILLSBOROUGH AMATEUR RADIO SOCIETY, 
INC, iHARS) Annual Tampa, Florida Hamfest, 
Sunday, October 12, 1969, Lowry Park.Sligh Ave. 
& North Blvd, Free Parking— Many Prizes. 

SELL: ART-13 Transmitter with maintenance 
manual, connectors, spare 813, 837, and 811's; 
$40, RME 435 A Receiver with book and some 
spare tubes; $60. PCA-2 Panadaptor, 455 khz, with 
book, needs work; $5, You pay shipping. K9KRW, 
Sox 436, Highland Park, IL 60035, 



142 



73 MAGAZINE 





MICRO*! 
AMP METER 



/ - 



200 



*^^^V^^- Texas 

Instrument" 

ISO WATTS 

HIGH FREQUENCY 



2N1907 



\ PNP 



urn 



Coll 
VGitagf 



Cirrrpnt 



150 



freq 

20120 

AMP Imc. 



1400-PC. GLASS FIBER OPTK KIT 



It's FUN* 



11 ^^ 



I *• ' 



*\ 



it's EducBtionatl It's Giftyf 

CI ^ Make light *'pfpes 
C4 QQ * Daizimg displays 
4>*f.O0 * Triggers photo t 

infrared cells 



»» 



.^ 



LIGHT 
GUIDE. 



orTlCAL SCIENTIJ-JC KREAKTH RU f 
AUuwti *'h»ir ihin" fflKan fibcm l2-rt. kitnf i 
til IranKivift 4 rrci#vit euld lirHt rnrmy uT 
any riilcur, by int^rnil rvllf^tiMn. Itundlrrl, 
jB^kptnl. il cutd«»^ «nuop«, ptprs Ur^^ 
jirriufiil mrnrrnir w»IU, #v«i in ctTT:t«>i^ Iriv- 

ACTS lik# wtrv. 
imMiriniitiAn rAnfraU 



4ii ti.-ililvl*V 



li CUTS. EiFJNDS. 
Only «nrV 
Itii TflOO's af v«^ 



mwvr^kM4iwr ilii, *Sth '^NjvIii' 



FAIRCHILD ' BRf^J? 
"FLAT PAK" RTL 
INTEGRATED CIRCUJTSs^* 

903-903* 3 Input Gate « «,..,,.,,,p.,,..$1 .69 

Half Adder $1*69 

JK Flip Flop $1,69 

J tV Flip Flop *f*^tt*^m^m**»*m $1*96 

Quad Inverter $1.69 

*First time anywhere two identical IC'a in one 
packag'e, example 923-923 contains two sepa* 
rate JK flip-flops in one package. 

EPOXY & ^METAL CASED RECTIPrERS 



900 

903-903* 

904-904* 

923 
n 923-923* 
D 927 



1 AMP 1000 PIV RECTrFlERS 

1 AMP 800 PIV RECTIFIERS 

2 AMP 1000 PIV RECTIFIERS 



5 for $1 

6 for $1 
4 for $1 



709/1/^^ 



LOWEST PRICES ON 
LINEAR AMPLIFIERS 

Guaranteed! With Spec. Sheets' 



»*» 



11" 



\* ' 



Type 
n 702 
3 709 
J 710 

a 711 



$2.22 s'o' 

Use 

DX. Amplifier 

Operational Amp 
OJfferentJaf Comparator 
Sense Amplifier 



lif11«1W'S1-fl 



MICRO MINI 

"PORaElAIN** 

1 AMP 



O 





PIV 


SALt 


a 50 


.05 


n 


100 


.07 


n 


200 


,09 


I 


400 


.12 


r ■ 


600 


.19 


1 


800 


.24 


n 


1000 


,29 






HAM 
StUCON 
TUBE 
SPECIALS 



(Replaces) 
niNT238 5U4G81 .. 

niN1239 5R41 , 

□ 1N2637 866A) .... 



piv 

50 
100 
200 
400 
600 
800 
1000 



1,5 AMP 



3 AMP 

n .15 

1 .19 
H .22 
H -31 

H -49 

n-79 



EPOXY SILICON 
TRANSISTORS 



5 for $1 



Type 
2N2222 
2N2368 
2N2711 
2N2368 
2N3396 
2N3565 
2N3568 
2N363d 
2N3641.3 
2N3645 
2N3662 
2N3683 
O 2N3793 
n 2N4248 
D 2N4284-5 
n 2N428a-9 
□ 2N4290 



Sale 
5for Jl 
5 for $1 
5 for $1 
5for$l 
5for$l 
5for$l 
5for$l 
5 for » 1 
5 for$l 
5 for $ 1 
5 for i 1 
5 for $ 1 
5 for »1 
5for$l 
5for$l 
5for$l 
Sforfl 



HIGH voir 

1 AMP 
EPDXY /^ 



Piv 

n 2000' 
D 3000 

n 4000 

Q 5000 
n 6000 
□ 8000 

n 10000 



SALE 

1.00 

1.35 

1.65 

2.25 

2.96 

3.50 

3,95 



'^ J.5 Amp rating 



1 AMP 



PIV 
50 
100 
200 
400 
600 
800 
1000 



D -32 



Terms: adii postaRe. Rated: net 30, cod's 2!S% 
Phone Orders: W;^kefielii, Mass. (617) 2l5-382i> 
Rgtaii: 211 Aihian, St.. W^ikefiyjd, Mass. 

filANT *JtMAS' CATALOG ON: Parti, RfCtifieri. 
.^ Transistfln, SCRs, UC.% Equipment, 1 Oc 

P.O. BOX 942 A 
Lynnfield. Mass, 

01940 



POLY PAKS 



400 



mc 



HIGH POWER 
UHF TRANSISTORS 

□ 2N3632 23W. 3A. 



7 AMP TRIACS 

PRV 
n 50 

n 100 

200 

[^ 400 



OCTOBER 1969 



143 



mmm 



LIBERTY 
PAYS 



MORE! 



LIBERTY 
OFFERS 



MORE! 



WILL BUY 
FOR CASH 

ALL TYPES 

ELECTRON TUBES 
SEMICONDUCTORS 
Military Electronic 

Equipment 
Test Equipment 



WIRE, WRITE, PHONE COLLECT! WE PAY 
FREIGHT ON All PURCHASES WE MAKE 



PRESTEl FIELD STRENGTH MEnR 

(Model &T4G} 

^ Never Anything Like It! 

% 7 !\/lan Can Do a Better Job 

than 3 in the Same Time! 

if A Gold-Mine for Antenna Installers! 

Frequency Range: 40 to 230 
and 470 to 860 Megaherin. 

Calibrated outword from 10 
to 50,000 Microvoitsp Nothing 
makes it easier to properly and 
speedily find the correct place 
to install TV, FM and Com- 

^ munication Antennas. You can 

measure and hear the signals 

volt battery economJcally powered 

nothing else like itl 



with this 4V2 
unit* There is 



Only $120.00 FOBN. Y. 



Liberty Electronics, Inc. 

548 Broadway, New York, New York 10012, Phone 212-925-6000 



40 METER SUPER GAIN ANTENNA 

See article in Oct. '69, 73; pg. . Potted, precut dipoie 7.2-7.3 iVIC. 2000 W PEP, 50 
Ohms; & wire for reflector screen. All u need is five 8' sticks. Only 7' above ground but 
much gain!! SI 4.75 PPD in USA. 



SASE for tech. data 



M 



OUSINR ENTERPRISES 



571 Orange Grove, Melbourne, F la. 32901 



INDEX TO ADVERTISERS 



JeH-Tronics 141 



Aerotron S7 


Epsilon 82 


AiTTateur Wholesale E lee 43 


Essco 115 


Aineco Books 1 1 


Evans 126 


American Crvstal 93 




Anrenna Mart 99 


Fair Radio 101 


Arcturus 138 


Freck 79-101 


Arnold 103 
ATV 5B 


Galaxy 1-41 
Gateway 140 


B «r F 133 

Barker 'Williamson 75 
8»9elow 65*121 
Bob*s AfTiaieur 67 


G & G 93 
Glass 131 
Global 101 
Good hear I 137 


Brigar 141 
Burghardl 97 


Hafstrom 23 
HAL Devices 35 


Cal book 57'97-140 


Hatrv 121 

HCJ 85 


CB Radio 95 
Coax Handbook 49 
Columbia 9B 


Heaih 5 
Henry 13 
H & L95 


DshI 93 


Instant Gourmet 105 


Denson 121 
DGP 63 


International Crystal 3 


Douv-Kev 27 
Dusina 144 


James Research 53 
Jan Crvstnl 75 



Lewispaul 137 
Lrberty 144 



Spectrum 103 
Stanley 82 
Swan 47 

Telrex 83 



MegarT 89 


Tower 140 


Meshna 142 


Two-Way 99 


Mlqrof ect 131 




Military Elec. 132 


UFO Net 121 




United Radio 139 


Natrona! Radio 21 


Universal 81 


New Ironies IV 




Pantronics 93 


Vanguard 23-31 67-79-91 


Park 122 


Vibrople^ 53 


Pickering 67 




PoiyPaks 143 


Western 95 




WR L 35 


QKernent 33 


Word OSL 101 


Radio Shop 103 




Radio Today 17 


73 IVlaga/rne ! 


Redline85-121 


Books 106 107 




Binders 81 


Sams 19 


Club Fmagle99 


Schober 89 


Gunsmoke 139 


Security 91 


Radio Bookshop 138 


Signal One III 


Subscnjjtions 1 15 


Slcip 103 





144 



73 MAGAZINE 



I 



COMPARE IT? 




...WITH WHAT? 



The CX7 practicaUy demands comparison. Question is * , . what to use for a standard? 
A transceiver? Or transmitter-receiver separates? 

You'il really need one of each. Don't forget power supplies, speech processor, keyer, 
directional wattmeter. Pick the best. In fact^ set up your "dream station'" ... at least 
on paper. NOW , . , 



WHATEVER YOUR CHOICE IN THE 

COMPARE IT PO I NT-BY-POINT with 

the NO-COMPROMISE CX7 . . . 

COMPARE the CX7 with any receiver for 
sensitivity, selectivity options, dynamic 
range, AGC merit, VFO smoothness, inter- 
ference rejection , . . 

COMPARE the CX7 with any transmitter 
for continuous power output in all modes, 
P. A. ruggedness, crisp audio punch, low 
distortion, instant CW break-in and spotting, 
quick band-change . . , 



COMPARE the CX7 with any transceiver 
for total size and weight , . , the extreme 
flexibility of its dual-channel system . . . the 
convenience of its completely selfxontained 
design . . . 

CONSIDER the CX7's incomparable fre- 
quency coverage and readout precision , , , 
aerospace-bred excellence in engineering 
and craftsmanship ... built-in "extras 
overall versatility . . . 
SEE WHAT YOU'VE BEEN MISSING? 



'7f Speaks for Itseir 



*t 



* < V 




Write for detaHed mchnicai information. 



A Division of ECl {An NCR Subsidiary J 
2200 Anvil Street N. •St. Petersburg, Florida 33710 



m 







( 





I 



THE ENTIRE BAND-BOTH CW AND 
PHONE WITH ONE TUNING ADJUSTMENT! 

10-15-20-40 METERS 

Only from HUSTLER wiU you receive the 
mechanical and electrical performance you want 
in a 4 Band Trap Vertical. Make the com- 
parison and see for yourself. 

Look what you get with Hustler! 

• Individually and precisely tuned traps! 

• Lowest SWR and Widest Band widthl 

• Outstanding mechanical construction! 

• Heavy gauge heat treated aluminum! 

• Stainless and cadimum pfated steel parts! 

• Base impedance nominal 52 ohms! 

• WHOLE BAND OPERATION WITHOUT 

READJUSTMENT! 

> FOR 75-80 METER OPERATION ADD HUSTLER MOBILE RM 75 
OR RM 75S RESONATOR ON TOP OF 4BTV, BAND WIDTH 60 TO 
100 KG. . , UNDER 2 TO 1 SWR 



MODEL 4BTV 



FIXED STATION 

TRAP VERTICAL 

ANTENNAS 



1 




See your 
distributor or 
write for 
new catalog 



I 



/ 



15800 Commerce Park Drive 

Brook Park, Ohio 44142 

Phone (216) 267-3150 



i