[R-390] R-390 IF: Looking for 20-pin socket and plug

[n4buq]

Here’s a picture. 

Thanks,
Barry
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> On Jun 12, 2026, at 12:48 PM, Barry via R-390 <r-390 at mailman.qth.net> wrote:
> 
> I have a 20-pin female connector that I believe was for an R390A.  I presume that's the same as for the R390 but I don't know that for sure.  Unfortunately, I don't have the male chassis mount part.
> 
> Let me know if you think you can use it.
> 
> 73,
> Barry - N4BUQ
> 
>> Everything has been going well on restoring my R-390, until I noticed no AGC
>> voltage.  Then I unplugged the 20-pin connector.  Lo and behold, pin 15 had
>> corroded right off (the AGC line)!  The mating plug has severe pitting and a
>> thick black oxide replaced what was once gold plating.  But underneath,
>> everything is pristine.  I am going to have to replace the pair.
>> 
>> A parts radio might yield them.  I would happily buy them.  An extender cable
>> would have this pair.
>> 
>> Interestingly, the Antenna Box BNC jacks were destroyed by pitting, but I
>> re-built that without thinking beyond it.  This reminded my of the circuit
>> breakers in a plant that made sulfuric acid.  Not only did the breakers fail
>> every few months, but the panels would grow long silver whiskers.  So there
>> was something in the environment of that radio... ?
>> 
>> Thank you,
>> WN9i Fred
>> 
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