Monday, January 23, 2023

Pioneer SX-980 Progress Report

 Still no sign of The Muse, but major progress was made this week! After being on the back burner for about a year ( ! ) I jumped back into the SX-980. I got stalled when I realized I couldn't continue with the alignment because the audio was constantly dropping out due to dirty switches in the signal path. Took a while and some forum searching ( I don't always care to watch YouTube vids...) to find out the right way to get the assemblies out for access. The front panel had to come off again to re-clean it, and once that was off, again, (what is it with me an front panels, anyway?) it was pull a bunch of screws and two control shaft nuts, and then lift the assemblies out the bottom:

Each one of the boards hanging out has push-button switches, lever switches, and/or rotary controls.

And they all needed cleaning.

The lever switches and rotary controls are easy to clean, as they're not sealed:

To get the cleaner into the rotary controls involved some improvising. I put a small piece of wire into the "straw" for the spray can, heated it gently, and bent it. I now have a "180* Adapter" for my spray can:

The push-button switches are a bit harder. Short of flooding or submerging the entire board in cleaner, there's no easy path to get the cleaner into the semi-sealed switch, and on the contacts. SO....we drill a small hole at the far end of the phenolic cover to access the cavity inside the switch. The holes I drilled are between the grey post sticking up, and the white hold-down clamp:

Put it all back together, and all the audio drops outs are gone. The controls and switches also function smoother, giving them a "quality" feel again.

So here we are, on the bench and wired up undergoing the alignment for the FM tuner and Multiplex decoder:


There's just something sooo coool about the incandescent lighting in these older radios.


After the alignment is finished, I have to repair the wood cabinet it goes into. SLW "bumped it and it fell over!" one day, causing the ancient glue joints to self disassemble......




6 comments:

  1. You are right. No LED quite has that warm fuzzy lighting of good old electric heat bulbs.

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    1. I've put LEDs in certain radios, but never a "classic" like one of these. They just don't look right....

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  2. Nice to see the work on the old Pioneer tuner. There seems to be a lot of tedious stuff like your previous restoration projects.

    I agree about the nostalgic ambience of the little incandescent lamps.

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    1. Yeah, tedious describes it pretty well. Lots of little fiddly bits to play with and adjust. Good thing we have forums for this stuff where experienced people share their accumulated wisdom.

      The only issue with replacement bulbs is who you get them from. Some of the Chinesium bulbs only last a few hundred hours, while others are equal to the OEM Japanese bulbs.

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  3. Progress is great! Those were good units back in the day!

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    1. Thanks! Got side-tracked by a plumbing issue today, so haven't done the amp testing yet. I'll be glad to get this in service again, as it's a much better radio that it's little brother, the SX-780 I'm using now. If I can find an SX-1080 at a good price I'll move up, but the SX-1280 and SX-1980 are way too pricey for me. Even junker SX-1980's go for a grand!

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Keep it civil, please....

Pioneer SX-980 Progress Report

 Still no sign of The Muse, but major progress was made this week! After being on the back burner for about a year ( ! ) I jumped back into ...