Crawls Backward (When Alarmed)

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Panasonic RF-2200 Mini-Restoration

Ok, I know.  I keep starting one project and then take on another simultaneously.  But hopefully this one will be quick, and it takes priority.  That's my story and I'm sticking to it!

Whatcha see here is the legendary Panasonic RF-2200 radio.  It has a reputation as one of the best performing radios on BC (AM broadcast), SW and FM ever made.  And this one is mine!

I just snagged it from another local radio-head.  If you do an interweb search, you'll see them going for crazy money.  But I got mine reasonably.  No way was I spending insane money for one.  This one had the typical scratchy controls, and needed a good cleaning.  And the whip antenna and gyro antenna were intact.  So a good deal.

I got to hear it before I bought it, and it seemed to be true to its reputation.  Amazing reception in a five minute test.  But once I got it home, the typical RF-2200 issues I've read about became obvious.  The controls were scratchy, and I found AM and SW to be intermittent in operation.  I knew I'd have to take it apart to clean it up anyway, so to the bench it went.

Five screws hold the back cabinet on.  The arrows show where they are.

My radio, naturally, has 2 of them missing.  I'm looking at McMaster-Carr's site to find replacements.

There is also this goofy, clearly non-original screw on the top of the cabinet near the antenna.  What's up with that?

Once the screws are removed, the back cover slides off.

There are four connections that have to be removed - two from the battery box (lower ones in this picture) and two for the whip antenna (top).  Fortunately, they have plugs that connect to the circuit board. 

The top of the circuit board is now accessible.

Lots and lots of adjustments for alignment.  I'm hoping the alignment is ok and I don't have to mess with it.

At the lower left you can see the tuning capacitor.  For sure I'll need to clean this.  It's a known source of issues on these sets.

Now to remove the front cabinet.  The control knobs and handles for the bandwidth and calibrator switches just pull off, then the cabinet cover pops off too.

The speaker leads have to be desoldered from the speaker.  There isn't a lot of room to work in there - I burned a bit of insulation off the wiring.  Doh.

And here we have the front of the cabinet removed, exposing the back side of the PC board.  I first want to clean the volume, and bass and treble pots as well as all the switches, and I should have enough access now.

To service most anything on the board, the dial drive assembly has to be removed.  I don't think I'll need to do that.  The service manual is online (thank goodness, see this page) and shows the procedure to do so. 

Here's the goofy bolt I mentioned earlier.  There must have been a fastener holding the whip to the cabinet that broke.  A previous owner ran a bolt through the cabinet to hold it on.  Maybe I can clean this repair up a bit.

The volume pot.  You can get easy access to spray cleaner into it.  But it and the other pots are held in with a plastic 'frame' that's molded to the cabinet - you can see the black plastic.

If you need to remove a pot, the whole circuit board has to be removed.

Fortunately for me, cleaning the volume pot fixes the scratchiness.  However, it doesn't resolve the intermittent AM problem.  I'm going to clean the bandswitch and tuning cap next.

 
 
 
 

Post a Comment 4 comments:

  • tom kildea said...
    January 29, 2014 at 8:39 PM
    Thanks for the information. I've got two of these babies, the first with similar issues to the one you describe, and the second with a deaf SW section. Do you do repair work for others? (I'm pretty sure I'm not up for it.)
  • Anonymous said...
    May 1, 2016 at 10:12 AM
    Mine has no AM/SW audio. Strong signal but zero audio. Any suggestions? Thanks
  • Yr Fthfl Blggr said...
    May 1, 2016 at 12:25 PM
    Hi Anonymous - on your audio issue, see the comment from J. Jarrett on my "Pt 2" post on this radio:
    http://crawlsbackward.blogspot.com/2011/12/panasonic-rf-2200-mini-restoration-pt-2.html?showComment=1460638966906#c5877602479608713915

    Aside from that, you'd need to use standard troubleshooting methods. I don't know your level of experience, and it's hard to give a complete answer here.

    A great resource is:
    http://www.antiqueradios.com/forums/viewforum.php?f=6

    Very helpful folks there.
  • Bryan said...
    June 13, 2016 at 8:48 PM
    The speaker connections are terminals on the main board. You do not have to unsolder them at the speaker.

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