Fw: [R-390] R-390A trouble (I FOUND THE PROBLEM)

[Jim Temple]

CORRECTION.  The pin number is pin 1 (one).  With all those leads, walls,
shields, and components to hack through, I miscounted the pin number.

It is PIN 1.

Jim

----- Original Message -----
From: "Jim Temple" <jetemp@insightbb.com>
To: <r-390@mailman.qth.net>
Sent: Friday, March 29, 2002 10:44 AM
Subject: Fw: [R-390] R-390A trouble (I FOUND THE PROBLEM)


> After wiggling almost all the leads to confirm security, I discovered the
> following.....
>
> Pin 5 of V201/6DC6, from the underside, seemed to be in place and secure.
> Upon wiggling, it seemed loose, so I gently tugged on the pin lead and it
> came out of the socket from below the plastic.  It was broken between the
> socket pin and where it emerges from the socket mold on the bottom.
>
> Apparently, there was enough contact to do the initial alignment, and
after
> a couple of hours burn in, it insulated itself, creating the below
symptoms.
>
> What was maddening was that the break was within the plastic mold of pin
5,
> which took a tug to break it from the plastic.  Three components are
> attached.  Later I will summarize what was affected and the fix.
>
> WOW......this is one for the books.
>
> I think I will go for replacement, but if there is an easy fix, I will
> consider it.
>
> Well, thats it.  Thanks for the support and help with this problem.  After
I
> complete the repair, I will post a summary of the symptoms and fix.  So
long
> for now.
>
> Regards,
>
> Jim
> 73, KF4ICZ
>
> ----- Original Message -----
> From: "Jim Temple" <jetemp@insightbb.com>
> To: <r-390@mailman.qth.net>
> Sent: Thursday, March 28, 2002 10:56 PM
> Subject: Re: [R-390] R-390A trouble
>
>
> > OK, I replaced C227 .047.  The old one measured .075 when out of
circuit.
> I
> > have a picked-over RF parts deck that happend to have this cap.  It
> measured
> > .04745, so hopefully this is the problem.
> >
> > HOWEVER, I am going to clean, inspect, wiggle, tap, eyeball, and
generally
> > give it the twice over before reinstalling in the morning.  I'm winding
> down
> > for the night.
> >
> > Will report back after reinstallation of the RF deck in the morning.
> >
> > Thanks for the great support and suggestions.  Good night.
> >
> > Regards,
> >
> > Jim
> > 73, KF4ICZ
> >
> > ----- Original Message -----
> > From: "Barry Hauser" <barry@hausernet.com>
> > To: <bill@iaxs.net>; "Jim Temple" <jetemp@insightbb.com>;
> > <r-390@mailman.qth.net>
> > Sent: Thursday, March 28, 2002 9:55 PM
> > Subject: Re: [R-390] R-390A trouble
> >
> >
> > > > 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
> > >
> > >
> > >
> > >
> > >
> > >
> > >
> > >
> > >
> > >
> > > _______________________________________________
> > > R-390 mailing list
> > > R-390@mailman.qth.net
> > > http://mailman.qth.net/mailman/listinfo/r-390
> > >
> >
>