[Milsurplus] CMS

[Richard]

More...  Keying the oscillator in the cathode the amplifier plate 
current will run away when key-up.  Alternatively, let the oscillator 
run and key the amplifier with J4, with B+ on the key, not a good idea.  
Similarly, in the receiver one stage of audio amplification will give 
good signal strength, with two stages you really need a gain control.  
My guess is it was never built.

Richard, AA1P

/4/20 7:49 PM, Hubert Miller wrote:

> What continues to puzzle me is the simplicity of the design, for 
> example, no gain control in the receiver, and
>
> the cathode modulation point, which would only work with the 1.5 volt 
> battery tubes installed. And the
>
> crudity of the schematic drawing, with the tube symbols looking like 
> something from the 1920s. The whole
>
> thing looks quite home – brew. That the government post – WW2 built an 
> AC power supply for it, and whose
>
> style is clearly much more modern, is just plain weird. If the 
> military needed a training radio, there were much
>
> better sets already being surplused !
>
> My thinking is that it was designed for some clandestine purpose ( not 
> a great leap of imagination ) but that
>
> it quickly became clear that it was too ham – hobbyist, took too much 
> ham radio type practical knowledge, for
>
> the newly minted radio operators. Like that loop of wire with a light 
> bulb, for tune – up, or a piece of plastic
>
> cloth to put over the key to keep you from getting a shock. Like 
> Mickey Mouse labs engineering. Altho the
>
> mechanical construction is well done.
>
> No one has ever seen a handcrank generator for this set. This is 
> another piece of evidence that ( so far )
>
> persuades me the set was never actually used in WW2.
>
> -Hue
>
>
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