[R-390] R-390A trouble

[Barry Hauser]

> Barry, I think you've got it.
>
> But I thought of another thing to try. Because the set is
> oscillating within itself, something common to the IF and
> RF decks is carrying energy between them.
<snipped>

Got what?  I dunno, but, hey, Bill, I think YOU"RE onto something.  Jim
should check out all those jumpers with the mini-BNC's -- maybe one of 'em
was swapped with that Skyhighgain cable Norman told us about.

Seriously, tho' -- wasn't that another thing that could cause weird
problems -- bad mini-coax?

When the rational, logical, informed, incisive, deductive approach fails ...
Well, let's consider ALL the clues ...

Squeal -- loud disturbing noise, alarm, or (sl.) to give information, to
"rat" on.
Happens over 3 MC's, that could be written as >3.  Looks like a bird, don't
it?
Motorboating, boats, water, ocean -- could be a seagull, or maybe
"putt-putt" = golf
Then there's the thing about cats.  Wait a minute!  A bird that looks like a
rat is a bat -- but then what's golf got to do with it?  This is going
nowhere -- might mean something to a witch.  Is Les around?

Forget all that -- pull the RF deck and check it out.  Could be an
"underneath-ARGHHH-do-I-hafta?" problem.  Give it the close eyeball
inspection.  By all means CLEAN the bandswitch -- twice. (unless I missed
something and you did that already)

Nobody seems to be focused on the >3 thing.  Why would this problem kick in
there?  What is different circuitry-wise about 0-1-2-3 vs 4+?  I guess one
thing might be a rotor section or two on the bandswitch, no?  Maybe not.
Any particular reason a bad cap would cause the squeal and motorboating to
start at 4 MC's?

Great, now I'm gonna be up all night 'cause of somebody else's radio.

Barry