OLD STUFF (Was: Re: [Milsurplus] Re: [ARC5] SCR-274N on ARRL.ORG

[D C *Mac* Macdonald]

I also built a W2EWL rig as my first sideband rig.  Note that I
don't call it SSB, as I  NEVER  was able to get the unwanted
sideband suppressed!  Tremendous carrier suppression, though.
I didn't have the knowledge or test gear to fix the sideband.

I now have a whole bunch of command set stuff that I hope
to have time to resurrect in my retirement (if I ever get there).
Some of it is in almost NOS condition and some is really junk --
only useful for parts.

I did build a single-tube converter back in 1961 to use in front of
a BC-453 to get better SSB reception on 75m than my Harvey Wells
R-90 could provide.

Back in 56-58 or so, I used one of the 1.5 - 3.0 MHz receivers as
the I.F. for a Morrow 5BR-1 converter; not as selective as the
B.C. or L.F. receivers, but the combo was stable, sensitive, and
reasonably selective for the A.M. operation of those days.  Foolishly,
I pitched it when tornado took our house, etc. back in 1999.  I
owned the thing for over 40 years!!!  I now have a replacement
to similarly use with a 5BR-1 converter recently bought on eBay.

I have also acquired a "twin" of my first full mobile setup, the
Gonset G-666B/G-77A twins.  Just found and bought a NIB G-66B
and matching power supply.  Now to find a G-77A in such a good
condition!!!

Wife (KA5BJS) thinks I'm nuts (she's correct) with all the  OLD  AM
stuff I have acquired.  Gotta have something to work on, right!!!

Anybody interested in Johnson stuff:  Viking II, Valiant, Viking Mobile???

73 - Mac, K2GKK/5
Oklahoma City, OK
(Licensed 30 Nov 53)



----Original Message Follows----
From: MillerKE6F at aol.com
To: jfor at quik.com, WA5CAB at cs.com, Glowbugs at piobaire.mines.uidaho.edu
CC: ezeran at ezeran.cnc.net, arc5 at ix.netcom.com, 
ARC5 at mailman.qth.net,milsurplus at mailman.qth.net
Subject: Re: [Milsurplus] Re: [ARC5] SCR-274N Makes It on ARRL.ORG
Date: Wed, 21 Jun 2006 12:54:24 EDT

In the context of the hay day of command set usage and the state of  the
art of TVs during that period and the state of amateur radio prowess in
dealing with TVI, the command sets in general even when run somewhere near 
their
rated power were a grand source of TVI.  I have some completely stock  
command
set units that I'd be happy to power up under stock conditions and  measure 
the
harmonic content and publish same in a few weeks as my curiosity has  become
renewed on this parameter.

2.  As to the Half Baked articles in CQ et al.  My point is  it is demeaning
to those adventuresome fellows that took the time to try and get  some 
utility
from this stuff.  Historically these folks should be enshrined  for at least
trying to do something with the glut of aluminum that WWII  produced.  
Hacked,
or whatever, these folks at least tried to do something  creative with the
stuff as opposed to the ever present appliance operators who  had the money 
to
buy commercial gear...

3.. Some folks have cited the stability of the command set VFO and to that  
I
agree completely.  When run at low potentials these rascals are a  monument
to good mechanical and electrical engineering.  However, the best  
conversion
practice with these units is to add a buffer between the oscillator  and PA 
as
vfo pulling is a reality on phone.  Not a big deal in the 40s and  probably
not a big deal even now with an am detector.  But a correctable  design
shortcoming (not a flaw...but a shortcoming).

4.  I too have used command sets from pure stock to using them as  platforms
for W2EWL ssb exciters.  What fun it was and the results varied  from pure
junk to Hey! not bad!  And what an education it provided.

     In closing, please keep the context of my arguments  and statements in
mind and lets all have fun with the command set stuff and show  a bit more
appreciation for the folks who at least tried to use them and perhaps  visit 
some
of the conversion projects that dotted the pages of CQ and other  magazines
over the years to see what drove the authors towards their  solutions.

73
Bob, KE6F

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