[R-390] Non-A version? Cost Reduction program. "Practicality" No. 3

[Charles A Taylor, WD4INP]

Les and Krew,

After X number of years, an item is removed from the list. I think that 
the R-390 has passed out of the window while the R-390A remains at the 
"edge."

This puts me in mind of a publication of Collins Radio Corporation that 
documents the process and rationale of the cost reduction program from 
the R-390 to the R-390A, and is titled, more or less, "R-390A Cost 
Reduction Program."

DOES ANYONE KNOW A SOURCE FOR A  "PDF" OF THIS DOCUMENT?

The R-390 was vastly over-engineered, mainly because its specifications 
were promulgated by zealous junior officers of the Army Signal Corps, 
despite Collins's attempt to get them to see the daylight. Even the 
R-390A is over-engineered.

The Crystal Oscillator subassembly oven is one example, but at least 
there was made available the option of turning it on or off with a 
switch on the rear apron of the R-390A. The operation of the Crystal 
Oscillator subassembly oven is totally unnecessary in any environment 
that you'un and me'un's gonna encounter.

That would be "Practicality Number 3, on my list of  "Practicalities."

Anyway, at least when yore front porch collapses under the weight of the 
refrigerator and the R-390A and kills ten hound-dawgs, the R-390A will 
survive.

Charlie WD4INP


Les Locklear wrote:
> The last time I checked this out, I was unable to find a NonA version 
> listed anywhere in Government inventories or a NSN or the older FSN 
> for a NonA.
> Is this part of the dumbing down of America?
> There were two versions of the R-390 series receiver built, not 
> counting the autotune models and several variants.
> 1. R-390/URR, this was the original receiver built by Collins and also 
> produced by Motorola.
> 2. R-390A/URR, This was the "cost reduced" version with mechanical 
> filters.
> Not very difficult is it? Or, maybe it is for some.
> Sarcasm mode off.
> Les Locklear