Yahoo Groups archive

Vintage Synth Repair

Index last updated: 2026-04-28 23:41 UTC

Thread

Update: more info about Korg Micropreset M500 problems

Update: more info about Korg Micropreset M500 problems

2015-02-20 by Malte Rogacki

As I expected: The problem was a broken trace due to a leaked cap. Cap
exchanged, trace repaired, presets work.


Looking through ebay it seems that many of the MicroPresets sold during the
last few months had this very problem. There's one on ebay UK with this
fault right now.


There needs to be continuity from the middle pin of S6 to TR24. This is a
very long trace that goes all over the PCB. In the vicinty of C50 this
trace was almost completely missing.

Arp 2600 questions.

2015-05-18 by Jim Blair

Hello! I recently purchased a 2600, and it plays great other than one significant issue. Osc 2 is reluctant to be properly calibrated. The other two oscillators are easily scaled using the front panel accessible trim pot, but number 2 is pretty cranky. I haven't opened the synth up yet, and I'd like to do some research first.

Any suggestions?


Thanks,

Jim Blair
Ape Island Sound

Arp 2600 oscillator scaling problem.

2015-07-14 by Jim Blair

Hello!

I've been working on my 2600 (recapped and calibrated PSU, replacing sliders), and am closing in on the biggest issue. Osc 2's scaling is impossible to calibrate. So I assume that something on the osc board needs to be replaced.

Any suggestions on where I should focus first?


Thanks,


Jim

Move to quarantaine

This moves the raw source file on disk only. The archive index is not changed automatically, so you still need to run a manual refresh afterward.