drumroll

A Sanyo DCX-8000K contains 65 electrolytic capacitors.

I know this because I love my DCX (as pointed out earlier): it's 70s-vintage and recently suffered from an occasionally crackly left channel, and thus it was due for some tender love and care.

So I replaced all 65 electrolytic caps yesterday, and also rigged the long-planned white LED dial lighting. The light stuff was trivial (the original bulb format is unobtainium nowadays and they get too hot for my liking anyway). The cap replacement was simple-but-not-easy: the DCX is all discrete hardware (except for just one 14-pin IC, the stereo decoder), lovingly distributed over a number of boards with wire-wrapped connections that I really truly didn't want to undo.

And of course, being me, I overdid it: I really should have done just the caps on the equalizer, preamp and amp boards. (Indeed there was one badly bulging cap on the left channel amplifier board. Even Rubycon caps are allowed to expire after almost forty years.)

No half jobs for me: I replaced the electrolytic caps everywhere, and the fiddly receiver board gave me loads of headache (lots of wires in the way, lots of caps in hard-to-reach places).

Alas, initial success was partial only: silence on the right channel when listening to FM radio (except when set to mono). sigh But I have the DSX service manual (complete with full schematics), and a Tektronix 2246 and I'm not afraid to use them :-)

...some poke ponder headscratch peek wonder...

In the end it didn't take too long to figure out what was wrong: I had soldered one cap with the polarity reversed, and all the stereo stuff needed readjustment (19 and 38KHz coils and FM channel separation).

Woheee!

[ published on Wed 16.12.2009 16:05 | filed in still-not-king | ]
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© Alexander Zangerl