[R-390] What is the difference between 390 and 390A

[Flowertime01 at wmconnect.com]

Bob,

>From 68 through 75 I was an Army Tech (33C) and made a living servicing R390 
and R390/A for literally thousands of Ops (05H) who made their living 
lessening to them.

>From the listen point of view, there were no signals either receiver could 
not hear. Would an Op copy the signal was a different subject?

The R390 IF does not ring like the mechanical filters in an R390/A a ditty OP 
did not care about the IF deck ring. Us SSB and AM listeners do notice the 
difference.

The R390 and R390/A are both bad mouthed for the AM audio quality. There are 
easy work around.

The R390 uses a pair of 6082 series voltage regulators that you can cook on 
(at least heat rations). With today power line voltages in the states the power 
supply regulation is over kill.

Sensitive wise the receivers are pretty equal and better than any thing else. 
The Army tried a lot of other receivers and the R390 R390/A were the 
intelligence intercept receivers of choice. When you need to roll up and down the 
bands chasing RTTY, and Dits on a demanding schedule The R390 and R390/A would get 
it on frequency and out of the atmospherics day in and day out.

Now if you just want to listen to a little AM radio on Saturday afternoon, 
there are some other options. 

Either model any manufacture. There all above average. Once you get it 
working again you will keep it working and wonder why you were ever without one.

Roger. KC6TRU