[Milsurplus] Navy Air-Net Monitor Receivers

[Hue Miller]

> Date: Sun, 28 Jun 2009 09:25:09 -0400
> From: "Robert Flory" <robandpj at earthlink.net>
> Subject: [Milsurplus] USN civilian rec's for aircraft watch
> I don't think I buy the SX-28 in that role.  Doesn't it have all those
controls that were found necessary to remove from the RBH, which was
also a ham set?  It is also physically large.  Where was your friend
reading this?
>
> RBS appeared on some bridges, like on NEW JERSEY.  Lean, compact set.
> RF

> Date: Sun, 28 Jun 2009 11:27:39 EDT
> From: WA5CAB at cs.com
>
> I'm inclined to concur.  The RBS was built for the role (bridge
radio).
> The base and -1 models have a splash-proof cabinet for the receiver,
suitable
> for bulkhead mounting.  The splash-proof rectifier/audio power amp
attaches
> to the bottom of the cabinet.  The -2 model came with mounting plates
that
> were to be attached to the top and bottom of a shelf or table.  The
receiver
> sat on top and the rectifier/amp hung from the bottom.  Internally,
the RBS
> is the same as the HF receiver of the RBM through RBM-4.  The front
panels
> are the same except that four of the knobs on the RBS-(*) receiver
have a
> letter engraved.  However, I can't find any explanation in the
NAVSHIPS manual
> for what the letters were supposed to mean.

The engraved - and possibly radium-painted letters on the knobs of the
RBS
are evident, such as B for band and T for tuning.
Now re the SX-28, I may have started that rumor myself. Looking back at
the
received email, part of which I will quote below, I see it's I who
claimed this
role for the SX-28. I may have conjured that from a Hallicrafters ad I
have
seen. I will have to pay attention to any reference I come across in my
reading to either support this or dismiss it.  I just looked at some
pages
from Navships 900,000.1 and I see in the list of "Safe" and "Unsafe"
receivers for shipboard use, the SX-28 ( Navy "RCF" ) is listed as
"definitely unsafe above 3 mc". However it is  "approved by FCC"
"When used with Radiation Suppressor Unit No. 1X381".  I have no idea
what that unit is, having NEVER seen or read elsewhere about this.
This is for the standard that field strength does not exceed 0.1 uV at
one nautical mile from the receiver. BTW, the list of approved receivers
states that the RBM, and thus the RBS, is safe except for the areas
"Band 4, 13 - 14 mc and 19 - 22 mc". Of course, no aircraft monitoring
would be done on those bands and in fact, very little actual Navy
traffic
of any kind would travel on those frequencies. BTW, another interesting
point, and I am not making this up, TCS is rated "Unsafe frequencies"
= "All",   unless equiped " with Majestic 'wonderbox' ".  Yes, that's
what
it says. I have never seen a "Majestic wonderbox". How many Navy
ships had "Majestic wonderboxes" on their TCS? ha ha ha. What's this
say about the radiation standards? Or were there strict instructions to
only use TCS in harbor?

Here are a couple more interesting sentences:
"Tests by the FCC and Naval Research Laboratory have shown
repeatedly that all commercial Hallicrafter receivers had local
oscillator radiations far in excess of the safe limit......
Commercial BROADCAST receivers can NOT be made safe
merely by the use of preselectors due to their usual "spread-out"
construction and and wooden or plastic cabinets...."
[emphasis on those 2 words was in the original.]
The article also states that the shipyard practice of making a gift
of a broadcast radio to the new launched ship's crew is ended.
Meanwhile I repeat, that I have not read of such "safe/ unsafe"
distinctions in the UK Royal Navy, and I note that the entertainment
receiver seen in the U-Boat radio room video on You Tube, that
radio, a Radione R-2, is merely a KriegsMarine badged commercial
broadcast radio. -Hue Miller

Now from the email I received:

"I bought an RME-69 and DB-20 set as last weekend's flea market, and
with
the manual were several copies of correspondence between Eric
Shalkhauser, founder of RME, and some previous owner of the receiver who
had apparently been researching the history of RME back in the 1970's.

There was the undated (?) telegram I have retyped below.  I am wondering
what receivers an aircraft carrier would have used which needed a DM-20
preselector.  RBB ?  RBC?  RAL ?  Curious.  I can't recall any original
photos of ship radio rooms showing the DB-20, but they were obviously
there.  North Africa would have pre-dated the use of VHF command radios.
------------------------------------------------------------------------

WESTERN UNION
CA329 GOVT  LG=  WASHINGTON  DC  29 1209P

TO THE MEN AND WOMEN OF RADIO MFG ENGINEERS INC=
PEORIA ILL=

A U.S. AIRCRAFT CARRIER WHOSE PLANES MADE 1,000 SORTIES
IN TWO DAYS DURING THE NORTH AFRICAN INVASION REPORTS
THAT YOUR PRESELECTORS HAVE PROVED INVALUABLE UNDER
COMBAT CONDITIONS. YOUR PRESELECTORS INCREASE THE RANGE
AND RELIABILITY OF COMMUNICATIONS WITH THE CARRIER'S PLANES
AND PREVENT RADIATION OF SIGNALS BY THE RECEIVERS WHICH
MIGHT DISCLOSE THE SHIP'S POSITION TO THE ENEMY. TO YOU
WHO MADE THIS EQUIPMENT BELONGS A SHARE OF THE CREDIT
FOR THE SCORE CHALKED UP BY THE CARRIER'S PLANES IN THE
NORTH AFRICAN INVASION: THEY SHOT DOWN 26 ENEMY PLANES
AND DESTROYED 100 ON THE GROUND HELPED TO SILENCE
BATTLESHIP SINK A LIGHT CRUISER AND FOUR DESTROYERS;
GAVE VITAL AIR COVER TO OUR LANDINGS STRAFED ENEMY TROOP
COLUMNS GUN EMPLACEMENTS AND OTHER INSTALLATIONS. WE
NEED MORE OF THESE EXCELLENT PRESELECTORS FOR THE
INVASION TO COME=

    E L COCHRANE REAR ADMIRAL USN CHIEF OF THE
    BUREAU OF SHIPS