Vintage Synth Repair

Change the capacitors, check the traces on the top of the board.
Check the position of the filters chips. It goes on oposite way position between them.


By the way... Anyone have a readable schematics ?


Marcelo Malmierca


On 19/08/2014, at 18:20, "b3bilco@... [vintagesynthrepair]" <vintagesynthrepair@yahoogroups.com> wrote:


I have one of these on the bench now with similar issues. Brass and Synthe 1 and 2 are weak, and the traveler slider has little or no effect. This tells me there's a filter problem. The envelope works on synthe 1's volume, just no filter sweep. I cannot read the chip # for the filter ICs on the schematic-not much of anything can be easily read on it, actually. I have repaired some eroded traces, but some run under 14 pin DIP ICs that I am loth to pull for fear of wiping out a non-replaceable chip, so  I am unsure if I got the whole trace right or not. There is output from the synthe and brass sounds, but weak and no filter action apparently. Anybody have a legible PCB trace layout on this beast? IC number/parts list? ANY HELP GREATLY APPRECIATED!!!!