Repair Korg MonoPoly Vintage Analog Synthesizer Reparatur Service
Korg MonoPoly restoration. This one came in with "unstable" oscillators and the request for a complete chek up. I found out that the "unstable" oscillator description were possibly caused by dirty potentiometers. The volume potentiometer was scratchy too. So I decided to clean them all.
This area of synth is well known (and old enough) for bad electrolytic capacitors. While I was in here I immediately spotted one leaky electrolytic capacitor. And another and another and... So I replaced them all. I used Nichicon and Elna electrolytics for that recap job.
After desoldering you can almost always spot a dark discoloration around the cathode side of the electrolytic capacitor.
These RIFA electrolytics are well known to blow up so I replaced it against a new, modern X2 safety capacitor.
Last, but not least, I cleaned the panel, knobs, case, wood, pcbs...
Caution
There are lethal voltage exposed in electronic devices. Unless you know what you are doing, don’t try this. If you following along, you doing so at your own risk.
I’m documenting repairs for my reference and yours.
I do synth restorations and repair with a specialty in vintage synthesizers, drum computer and other vintage gear, based in Düsseldorf, GER. Get in touch about your synth situation!