[R-390] R390 progress

[AI2Q]

Dan, et al:

Pulling the RF deck out and re-installing it is not difficult---even if you 
didn't have the green gear. I was entirely successful with my R-390 
restoration (see the archives for details) and my set was missing the gear. 
I simply held the gears in place with duct tape (!) while dropping the 
chassis back in. Followed the instructions in the TM to the letter. Worked 
just fine.

GL es enjoy a great old piece of equipment.

Vy 73, AI2Q, Alex in Maine
http://users.adelphia.net/~alexmm/ai2q.htm

----- Original Message ----- 
From: Dan Merz
To: Flowertime01 at wmconnect.com ; r-390 at mailman.qth.net
Sent: Wednesday, April 27, 2005 2:27 AM
Subject: RE: [R-390] R390 progress


Roger,  I started thinking about pulling the 390 rf chassis and was looking
at the manual to see what was involved.  I haven't had the front panel off
yet so the first task will be getting those panel screws out without
snapping one off.  This was my first mistake when I pulled the panel off my
390a - haven't gotten the broken screw stub out to date - it reminds me to
be more careful on screws that haven't been out for a while.  But that
aside,  the green gear is there;  I found one confusion in the manual copy I
have;  should the meghz knob be set to 00  or 10 before pulling the panel
and rf chassis?  It seems 00 would be the logical setting since the cams are
mostly near high points there.  I'm warming my mind up on what it involves
but am still playing around with the other kinds of diagnostics first. I did
replace the two oscillator tubes with 6AK6W's,  which I found in my cache.
I got it working somewhat better on the "bad" bands by pulling out the two
rf tubes and the 1st mixer tube,  testing them and then putting them back in
!! Maybe one wasn't seated well or a dirty contact. I probably should put a
little deox on the tube pins here.  They are some of the easier ones to
pull.  I have a variety of brands to try later.  Since the 1st mixer is used
only for the lower bands,  I thought maybe the problem was there.  But
dinking with the iron cores/trimmer caps in that stage didn't improve signal
getting thru much.  More later,  Dan.

-----Original Message-----
From: r-390-bounces at mailman.qth.net [mailto:r-390-bounces at mailman.qth.net]
On Behalf Of Flowertime01 at wmconnect.com
Sent: Tuesday, April 26, 2005 1:42 PM
To: r-390 at mailman.qth.net
Subject: Re: [R-390] R390 progress

Dan,

I sounds like Tom said Jerry said, the whole world knows you need some
6AK5 / 5749 in your R390. Not something you have to do, but you will likely
hear more with some 6AK5.

Now your looking for tubes, The first thing there is all brands are not
equal.
Take what you can get today and try them. Do not pass up any swap meet
bargains and take those home. Try them. Swapping tubes is the difference
between very good receivers and really awesome receivers (my to cents) A
tube will not fix a problem that is not the tube. But once you get all the
problems fixed, then tubes do make a difference.

You may yet need to pull the RF deck to change some caps. Do some more
reading and lets see if we can get you the whole list of things to check for
before we send you off to just yank the RF deck for fishing venture. There
are lots of other specific not invasive test that can be conducted before we
send you down that path.

If you were a student in the 33 or 31 MOS an instructor would not hesitate
to make you pull that deck on the drop of a cigarette butt. However you
would also have been trained and psychologically conditioned to do the task
prior to jumping in. For 33's that instructor was a hell of a lot more scary
than any piece of hardware.

Roger KC6TRU

_____________________________________________________________
R-390 mailing list
Home: http://mailman.qth.net/mailman/listinfo/r-390
Help: http://mailman.qth.net/faq.htm
Post: mailto:R-390 at mailman.qth.net
Unsubscribe: http://mailman.qth.net/mailman/options/r-390


_____________________________________________________________
R-390 mailing list
Home: http://mailman.qth.net/mailman/listinfo/r-390
Help: http://mailman.qth.net/faq.htm
Post: mailto:R-390 at mailman.qth.net
Unsubscribe: http://mailman.qth.net/mailman/options/r-390