[R-390] Where would you start?

[Barry]

Tracy,

A few weeks ago, I replaced some out-of-spec components on the underside of
one of my IF decks.  When I put it back in place, I noticed the bandwidth
selector no longer had any effect.  I got the same bandwidth no matter what
position I selected.  I scratched my head for a while and then realized I
had removed the bandwidth selector switch's shaft (the one that connects it
to the front panel of the IF deck) so I could more easily get to some of the
parts.  Duh.

As if that wasn't enough, a week or so ago, I was fiddling around with the
5814A's in the same IF deck.  I was seeing the differences one tube or the
other made in the AGC amplifier socket.  One of them gives good grid voltage
and the others don't.  When I started trying to listen to it again, I
noticed some of the same symptoms you describe.  I then looked and noticed I
had failed to plug one of the 5814A's fully back into its socket.

Those kind of things happen.  ;-)

Barry - N4BUQ


----- Original Message -----
From: "Tracy Fort" <beerbarrel at cox.net>
To: "'Francesco Ledda'" <frledda at verizon.net>; <R-390 at mailman.qth.net>
Sent: Sunday, March 19, 2006 12:05 PM
Subject: RE: [R-390] Where would you start?


Thanks for all the replies guys. I write this as I sit here red faced....

It's amazing what happens when you put the Diode load jumper back in.....

Tracy

-----Original Message-----
From: Francesco Ledda [mailto:frledda at verizon.net]
Sent: Saturday, March 18, 2006 8:40 AM
To: Tracy Fort; R-390 at mailman.qth.net
Subject: RE: [R-390] Where would you start?


What kind of speaker are you using?

-----Original Message-----
From: r-390-bounces at mailman.qth.net [mailto:r-390-bounces at mailman.qth.net]On
Behalf Of Tracy Fort
Sent: Saturday, March 18, 2006 6:33 AM
To: R-390 at mailman.qth.net
Subject: RE: [R-390] Where would you start?



Paolo,

I'm so-so at it. I'm not close to an expert though. I do have the manual. I
was just hunting quick things to check. I can't tell is sensitivity is Ok
because volume is quite low. At this point, I'm thinking that it's only
audio. I'm think I might check for the leaky cap at V507 tube socket. I lose
volume completely if I turn off limiter switch.

Thanks,
Tracy

-----Original Message-----
From: paolo gramigna [mailto:paolo.gramigna at controllo.it]
Sent: Saturday, March 18, 2006 7:20 AM
To: 'Tracy Fort'
Subject: R: [R-390] Where would you start?



Are you familiar with servicing a vacuum tube radio? Do you have the R-390A
manual? You can get it here: http://www.hausernet.com/r390a/ if you don't.
those radio will loose plenty of sensitiviti if just one of the RF slugs is
off by a millimeter or so. You will need a few test instruments, and a few
special tools (bristol key). Let me know about your situation...

Paolo


-----Messaggio originale-----
Da: r-390-bounces at mailman.qth.net [mailto:r-390-bounces at mailman.qth.net] Per
conto di Tracy Fort
Inviato: sabato 18 marzo 2006 12.53
A: R-390 at mailman.qth.net
Oggetto: RE: [R-390] Where would you start?

I got carrier level to come up but no audio impoovement.

Tracy

-----Original Message-----
From: r-390-bounces at mailman.qth.net [mailto:r-390-bounces at mailman.qth.net]
On Behalf Of Tracy Fort
Sent: Saturday, March 18, 2006 6:42 AM
To: R-390 at mailman.qth.net
Subject: [R-390] Where would you start?


Just got a new 390a the other day. It seems to have arrived with a little
problem. It has extremely low audio output. I don't know if something was
shaken loose in shipping or not but it all looks good and was packed well.
Tuned to a local AM station with rf gain and audio maxed out I can barely
hear audio. I get very little carrier reading. It's slightly above zero. No
movement on the line meter either. I'm trying to figure out if it was
working OK before it was shipped and am waiting on a response from the
seller. I'm pretty sure that it was but wanted to make sure before I started
getting to deep into it. Are there any problems that jump out at anyone
right away that could be easy to check?

Tracy