[R-390] R-390-A problem

[Rasputin Novgorod]

> I, too, was frustrated when my audio
> volume suddenly faded after being in operation for 5-30
> minutes.
> There a poor electro-mechanical connection in the phono
> plug. 
> 
> When the SAME phenomenon occurred a decade later: it was a
> loose screw on the speaker terminal strip causing an
> intermittent !

My friend and I are restoring a Harris RF-270-5A 
1 kiloWatt Transceiver, which fills a complete 6 ft rack.
This is after it saw, perhaps 3 decades of continuous 
Airforce service, then sat dormant in my shop for 6 years.

After about 30 hours of troubleshooting, we have it 
mostly working. We found ~no~ defective "active"
electronics. Only a couple of resistors whose value
drifted too much.

All the faults were fixed by reseating cards, cleaning
switches, plugs, pots, relays, etc. It's amazing how
reliable vintage electronics is. Hence, when servicing
R-360s, we need to remember Occam's razor.

I have another fiend (sic) who services CD radios. The
first thing he does is hooks it up on the bench
and tries it. Then he (rather shockingly) slams it
down onto the bench several times. He feels this
"shakes loose" the problems. After it is repaired,
he repeats his violent test, just to make sure...

He claims this test has dramatically reduced returns.

Sincerely
/b