[R-390] Capacitor Replacements Vitamin Q

[Barry]

> My opinion....
> 
> The R-390/URR was what we know as "Military Grade".
> 
> The R-390A is more closely "Consumer grade" as far as their capacitor 
> choices were concerned.  I have seen as many problems with the Brown 
> Tubulars as the Black ones.  I have several cracked in a radio I'm working
> on right now.  It's not an SJC survivor either..before someone throws that
> flag...
> 
> Approach the suspect accordingly...
> 
> My usual approach is to do a sample test of caps in places that are not
> critical.  If a high percentage come back leaky at rated voltage then a
> wholesale replacement of "Paper" caps is in order.  I'm only speaking of
> paper caps not micas or others that are known to be fairly reliable.
> 
> Cecil
> K5DL

That "Military Grade" thing is good to know.  I was fortunate to find a very nice R390 with lots of extras on the local Craigslist this past weekend and it's now resting in my workshop.  It needs a bit of attention but not much.  Looking forward to seeing it occupy my CY-979A.

Barry - N4BUQ