[R-390] Is anyone selling R-390A Cap kits?

[2002tii]

Bob wrote:

>I have an R-390A that is in desperate need of a cap overhaul.
>      *     *     *
>I trust Orange drops are OK or should I use something else?

1).  Unlike many other boatanchors, 390As were built with 
mil-qualified caps.  The mil-qualified paper caps have exhibited much 
lower failure rates over time than the commercial paper caps used in 
other radios (e.g., SP-600).  Consequently, except for the few "high 
risk" caps, I very much doubt that your 390A needs wholesale cap 
replacement unless it has been subjected to extremely unusual 
conditions (in which case, the caps would probably be the least of 
your worries) or was manufactured using commercial caps (there may 
have been production runs with commercial caps, but I don't know of 
any off the top of my head).

2).  If you insist on shotgunning the caps anyway, Series P225 Orange 
Drops are better than the original paper capacitors.  However, if you 
are going to the trouble to replace them, you can improve the 
bypassing if you replace the paper bypass capacitors with 1 kV disk 
ceramics instead of ODs.  Most of the caps in the radio are bypass 
caps.  However -- NOTE: do NOT replace AGC time constant caps or IF 
or AF coupling caps with ceramics.


Best regards,

Don


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