[Milsurplus] GO RAX more...

[Hue Miller]

Date: Thu, 9 Jun 2011 20:54:09 -1000
From: "Kludge" <wh7hg.hi at gmail.com>

> When the German paratroopers showed up on the front they were found to
> be using 28-30 Mc. There was a scramble to obtain receivers that could
> tune that range.

That's above the tuning range of the RAT(-1), RAV and RAX but within the
range of the Admiralty converted BC-455s.  Hmmm ... Okay, I'm not going to
start speculizing.  :-)

> doubt the U.K. would find it worthwhile to spend a lot of time listening
for skip propagation
> signals there. For example, the strongest tank radios were 20 watts, and
pack radios
> commonly a couple watts.

On the ground, 'tis likely true.  But the advantage of altitude changes the
rules somewhat.  We had receivers (The AN/ARR-5 and AN/ARR-7 come to mind at
the moment.) that could manage that trick rather nicely and were part of
on-board surveillance/countermeasures suites.  Again, though, this falls
pretty much in the range of the Admiralty converted BC-455s.

-Let's think about this. You have localized, low power, ephemeral, sporadic
German voice coms in the 24-38 Mcs. range. You need a well trained
German language translator onboard your aircraft, to exploit the intercept
in real time.  Or a practical recording
system, this to collect combat voice communications. Why? You also need
to maintain your flying platform, and its protective air cover, for how many
hours? If you get the recordings back to London, what are you going to do
with recordings such as "Green; Green 5, are you bringing up more MG
ammunition now?"
If your goal is to jam the German radios, the pack radios are all VFO types
and so are the armored vehicle radios.

> I think the HF RAXs and GOs were kind of an alternating mistake. Using a
GO for position
> reports on the squirrely 20-26 MHz freqs strikes me as ludicrous. Not to
mention, I
> wonder how stable the PA stage in the GO would be at such frequencies.
When the RAX
> appeared, it seems the mistake had already been rectified by limiting the
high freq end on
> the new GO-9. It does seem there are quite a few RAXs around tho, which I
cannot explain;
> tho not nearly as many as BC-348s, which the Navy to some extent used to
replace the
> RAX, and which wrote off any freqs above 18 MHz.

Taking things out of order, the Navy didn't replace the RAX with the BC-348
but rather got them as part of AN/ARC-8 installations aboard aircraft
acquired from the AAF.

-I have a "gotcha". I talked with a PBY ( Cat ) radioman who flew out
of E Coast on Carib patrol, Chet Wisner. I do not know if he's still around,
will have a look later today. I have a copy of he using a mill in the 
aircraft
but unfortunately for us, no radio equip shows up. He flew out of Maryland,
does that sound right - this is my memory guess only.  Told me in '43 the
GORAX eqpt in his PBY was changed out to the BC-348 ART-13 ( I suppose
it would be ATC ). He did not have insight into WHY and perhaps, I suspect,
even assumed these were Navy-wide changes. Anyway he was thrilled with
the new equipment, positively did regard it as a strong improvement. ( Pete
Peterson told me that it was a bit of a hassle to retune the GO for position
reports. )

At the same time, the GO-7, -8 and -9 also stopped
at 18 MC which indicates to me that the Navy found the higher frequencies
inadequate to their needs or stopping at 18 MC adequate to their needs, one
way or the other.  On the other claw, they must have had some reason to at
least attempt using the 18-26.5 MC range or they likely wouldn't have tried.

-As I said, I have real doubts that the skip propagation at 27 MHz would 
work
out well for long distance liaison comms. Think about how iffy 10 and 11 
meters
is. The German comms in this band were local, ground wave and line of sight.
( For the Germans, ground wave coverage was enhanced by tactical comms
in the (mostly) 1000 kcs  - to single digit HF, including down below the MW
BC band....)

I can't speak to the stability of the transmitters.  Someone else will have
to take care of that detail.  However, I would suspect they were as stable
as the rest of the GO line since they would have to meet the same specs
aside from frequency range.

-What I was thinking of, is you have a transmitter which includes ALL the
loading coil business for short high capacitive impedance antennas as well
as series capacitance variable to cope with antennas that are "too long"
for say, 11 meters. Having seen the inside of the GO-9 transmitter, I have
to wonder how they pulled this off, without the final getting squirrelly to
tune up, I mean as in unstable, not just frequency stable but tending
to run away. But this is unsupported, just a wondering.

> One thing that amazes me, is how thoroughly and quickly technologies and
> specialized knowledge could disappear from the face of the earth, in
pre-internet times.

While as an historian it is utterly frustrating to say the least, if I drop
back and look at things from a more practical viewpoint, it's perfectly
reasonable.  Documentation and equipment have shelf lives that expire the
moment they're not needed anymore.  Thankfully bureaucracy moves slowly or
we wouldn't have some of what we do today.  Also, the supplying of surplus
to the various surplus postwar shops (that were, as I recall, opened by
returning vets as part of a rehabilitation program) played a large part in
preserving at least some of the equipment.

Best regards,

Michael, WH7HG ex-K3MXO, ex-KN3MXO, WPE3ARS, BL01xh ex-Mensa A&P PP BGI

Yes, true. Once something is obsolete, for the near term history, it is just 
"in
the way" of getting things done, and a cost.
I'm also thinking of another modus, and that was the military's procedure 
for
disposing of "early edition" or higher-classification manuals, for examples
countermeasures. That seems to have been VERY effective.
-Hue