via this auction
This one does need work. Hopefully we'll see SN 3780 working again soon. Pics of the inside below and some details via the seller:
 "I took everything apart and cleaned it inside out and replaced the key bushings with the correct recommended ones and lubricated them and the plastic key pads with dow corning 7. There was ONE spring missing under a key (I might have lost it during break down and rebuild) so I just used a larger, shorter stainless steel spring (pictured).
"I took everything apart and cleaned it inside out and replaced the key bushings with the correct recommended ones and lubricated them and the plastic key pads with dow corning 7. There was ONE spring missing under a key (I might have lost it during break down and rebuild) so I just used a larger, shorter stainless steel spring (pictured). After putting everything back together I shot a video that shows that many of the keys do the ramping/sweeping that happens possibly with the old contacts. I did clean all the contacts which seemed to help but the video shows the sweeping/ramping that still exists. I don't know if all the functions work they way they are supposed to because I've never had an analog synthesizer and I'm very new to Oscillators, filters and the like of this fascinating synth.
5 of the keys have degrading, or the tops have a little bit 'eaten' away? the 3 worst ones are pictured close up. You can still hit the key, it's just an ugly cosmetic thing..."

 






































