Electric Radio 223 2007 Dec.pdf

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celebrating a bygone era
ELECTRIC RADIO
Published monthly by Symbolic Publishing Company
PO Box 242, Bailey, Colorado 80421-0242
Periodicals postage paid at Cortez, CO
Printed by Southwest Printing Inc., Cortez, CO
USPS no. 004-611
ISSN 1048-3020
Postmaster send address changes to:
Electric Radio
PO Box 242
Bailey, CO 80421-0242
Copyright 2007 by Symbolic Publishing Company
Material appearing in Electric Radio may not be used in any
method without prior written permission.
Editor
Ray Osterwald,N0DMS
Editor Emeritus
Barry R. Wiseman, N6CSW
Electric Radio is all about the restoration, maintenance, and
continued use of vintage radio equipment. Founded in May of 1989
by Barry Wiseman (N6CSW), the magazine continues publication
for those who appreciate the value of operating vintage equipment
and the rich history of radio.
It
is hoped that the magazine will
provide inspiration and encouragement to collectors, restorers
and builders.
It
is dedicated to the generations of radio amateurs,
experimenters, and engineers who have preceded us, without
whom many features of life, now taken for granted, would not be
possible.
We depend on our readers to supply material for ER. Our pri-
mary interest is in articles that pertain to vintage equipment and
operating with a primary emphasis on AM, but articles on CW,
SSB, and shortwave listening are also needed. Photos of hams in
their radio shacks are always appreciated. We invite those inter-
ested in writing for ER to write, email, or call.
Regular contributors include:
Chuck Teeters (W4MEW), Jim Hanlon (W8KGI), Torn Marcellino (W3BYM),
Gary Halverson (K6GLH), David Kuraner (K2DK), Bruce Vaughan (NR5Q),
Bob Grinder (K7AK), Larry Will (W3LW), Dave Gordon-Smith (G3UUR), Dale
Gagnon (KWII)
Editor's Cornrnerrts
2007 Holiday Season
The 2007 holiday season is once
again here. I would like
to
thank all
subscribers and contributors to Elec-
tric Radio for your support this past
year, and I hope that 2008 is a happy
and prosperous year for everyone. I
have learned this year, again, that the
A Radio Christmas in the Elmering
vintage ham radio community is a big
Tradition!
family that I am proud to be associated with.
2007 Heavy Metal Rally
Please remember the popular, annual Electric Ra-
dio Heavy Metal Rally that is on Saturday, December
29 this year. The rules were printed last month in ER
#222.
I am planning on operating from Rod Perala's
vintage radio museum, W5CZ, in Indian Hills, Colo-
rado, that evening. This will hopefully be a multi-
operator station, and will be a great opportunity for all
to hear and to work a lot of the excellent, classic
equipment that is at W5CZ. I hope
to
work as many stations as possible and say
hello to everyone!
Honor Your Elmer Contest: Time To Vote!
The first-ever "Honor Your Elmer" contest has ended November 30,2007. At
the time of this writing, we have received 34 excellent entries in the contest.
(Continued on page 2)
TABLE OF CONTENTS
3 Five Tubes, Five Bands, Fifty Watts: a Homebrew Transmitter
K8WPI
W5DRN
12 National NC-183D Solid-State Rectifier Modification
15 QSL Cards
NR5Q
23 Modifying a Fair Radio Sales BC-348 Power Supply
WA2CBZ
26 Army Engineer Communications in Vietnam, 1967 to 1968, Pt. 2 W3LW
34 The Knight-Kit TR-108 2-Meter Transceiver
K7SC
36 Radiola, The Golden Age of RCA: A Review
K7AK
43 Bandwidth-Based Coordination Scheme Again Stings ARRL
WA3VJB
47 Vin tage Nets
ER Readers
48 Classifieds
ER Readers
Although this is not as many as we would
have hoped to received, it is still a good
amount. All of the entries have been
posted on the Electric Radio web site.
When I read the Elmer stories, I am
revisiting some almost-forgotten ham
values of a bygone era and I have a
colorful stroll down memory lane to a
time when hams helped each other as-
pire to higher things, had to copy code
and draw schematics for Hardey and
Colpitts oscillators to get their radio
tickets, and dogs ate solder.
To make this contest a success, it is
time for all readers to step up and vote
for the best story. Voting will mean that
we can fairly select the winning stories
and honor those writers who have taken
time to send in their stories and enter
the contest.
To vote for the best story, you need to
go the Electric Radio Internet web site,
(www.ermag.com) and click on the
graphic on the left side of the opening
page that shows a fellow operating a
Hammarlund receiver. That will take
you directly to the Elmer entries.
A list of all the stories will appear, and
clicking on the titles will bring up the
text that is underneath that particular
title.
Once all of the stories have been read,
write down your favorite author and
send it to me by email, US mail, or call
me on the telephone. The author of each
story is written at the start of each one.
The voting criteria should be that the
story is well written, is about the Elmer
and not the writer, and that you like it!
Other than those simple guidelines, there
are no other rules.
Photos Needed
Right now, I am getting quite low on
photos to use in the magazine. I am
always looking for photos of ham events,
great-looking shack photos, and any-
thing else that applies. Nice photos for
the cover are always appreciated!
73, Keep Those Filaments Lit!
2
Electric Radio
#223
December 2007
Five Tubes, Five Bands, Fifty Watts: the Evolution
of El Jefe (the Chief), a Homebrew Transmitter
By James "JeRB" Buchanan, K8WP1
9549 N 17
T h
St
Kalamazoo, M1 49009
oldbugger@copper.net
Don't get me wrong, I absolutely love
Throckmorton, my big transmitter, how-
ever, the concept for £1 Jefe was actually
inspired by Throck, all that is good, and
all that is overdone. Not that overdone is
necessarily bad, but sometimes it is bet-
ter to be humble. So, £1 Jefe was to be a
bit less cumbersome
to
build and per-
haps, to operate. A little more "nimble"
would be a good word, by not covering
the entire HF spectrum, but just where
I spend most of my time; comfortable,
like an old pair of shoes. Just for a
change, having a modest power output
and a tube design. Keep the best of the
best, try new ideas and see what hap-
pens, and see if it can be done.
The VFO Design
During design, one of the things which
impressed me the most about Throck
was the stability of the Vackar VFO.
Designed in the 1930s, the Vackar has
always enjoyed a "cult following," and
received much attention in a series of
articles in
Ham Radio
magazine in the
1970s. My selection of the Vackar was
primarily for its linear, uniform, broad-
band output in a rig which tunes 500
kHz at a crack, but the absolute fre-
quency stability really knocked me out,
begging the obvious question, could a
frequency-multiplying rig be viable in
the 21 Century? Giving the matter
lengthy, casual thought suggested mul-
tiplication could be a reasonable ap-
proach, but how do I deal with narrow-
ing bandspread with multiplication,
which I have always felt is a big flaw in
this approach. Many hams have sug-
gested an on-frequency VFO is a prob-
lem, as it is always running, and have
asked me how I deal with that. "I key the
VFO" is my standard reply. A discus-
sion always ensues. I don't know if it is
urban legend or a throwback to poorly-
designed rigs that has people convinced
VFOs can't be keyed without causing
S[
The front-panel view of "El
J
effe," a custom-designed, homebrew transmitter is easily
recognizable as a vintage rig, but not quite identifiable.
It
fits nicely into a vintage
shack.
Electric Radio #223
December 2007
3

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