[Milsurplus] More idle CMS speculation

[Hue Miller]

More factoids and observations to put in the input hopper.....

1. The CMS and CMR are very competently built, very nice quality of 
construction,
and very compact.
2. Nowhere on the radio is there a U.S. Navy or ANY U.S. military 
identification.
3. The schematic on the other hand, looks like some unsophisticated ham 
might
have designed it:
* the receiver is straight simple 3-tube regen with no gain control and 
transformer audio
coupling, the simplest design.
*the schematic is rather crudely drawn. The tube symbol shows the plate as 
an actual
rectangle inside the tube circle, and this rectangle is "shaded" ! as if to 
show it's solid.
*the AM facility is a mic jack in the oscillator stage - that's all! I 
wonder how class C
amplification of a low-modulation level of an oscillator, would sound! Maybe 
it even
sorta worked!
4. The transmitter tube sockets for the 2 6V6  or 6L6 are wired as TRIODES. 
I looked
at some tube pinouts the other nite and there are a number of other tubes 
which
would appear to be usable in the same socket: 6J5, 6P5, 1P5, some others 
which I
do not recall now...
5. The CMS system, altho spy-looking, showed up in a later  1944 or later 
Navy
catalog I saw - where its designation was NOT confidential, same as any 
other
Navy radio, and its purpose was described as "to communicate with similar 
units".
6. Altho the cabinet is not really ruggedized, it is quite compact and I 
noticed there
is some kind of rubber gasket on the lid, so there is at least an attempt at 
moisture
proofing. I suppose the plain wood cabinet finish is less military-looking 
than
Navy grey or Army green.

I peeked at the back of the calibration charts tacked to the radio front 
cover, hoping
there might be hidden there a revelation of the whole story. Of course - 
nothing.

My SEG (semi educated guess):
This radio produced in a period right after Pearl Harbor. Hurried into 
production by
some local Navy activity - thus, no input on design from actual electronic 
engineers -
and thus the fully competent mechanical construction - and thus the seeming
crudity of the schematic. So I'm suggesting the radio was the product of a 
kind of
panic. No one knew if the Japanese were going to invade West Coast points.
Perhaps the CMS was intended as a kind of coastwatcher or stay-behind unit
radio. Later, as it became clear that Japan in no way had resources to 
attempt
anything like this, I suspect the CMS was downgraded to fit into regular 
Navy stock.
I also suspect none were ever actually used. The 2 I have seen up-close had 
no
signs of any actual use-wear.
-Hue Miller