[Milsurplus] R-390 hints

[Kenneth G. Gordon]

On 6 Oct 2019 at 13:23, Peter Gottlieb wrote:

> I am not too familiar with the differences between the 390 and 390A.

There are two main differences between the two receivers: 1) the 390A does not have that 
too-fancily, unnecessarily complicated, designed and built regulated power supply that the 
390 has, and 2) the A model has mechanical filters, whereas the 390 has LC filters only.

In point of fact, the 390A is a cost-reduced version of the 390.

Some people believe the 390 was a better receiver than the 390A. I tend to agree.

Since for certain applications (DF, I think was one) the mechanical filtered-IF caused 
significant problems, there was one model of 390A which had the entire IF strip changed 
over to the 390 model's LC filtered IF strip.

I don't know how many were done like this nor when, but they are not particularly "rare".

Ken W7EKB