Minimoog D notes constantly sounding

[willstring]

Hey all,

I'm currently an owner of an older 1974 Minimoog D (old oscillators board) that was working pretty much perfectly until recently. The problem is pretty simple; When I turn the unit on and play a note, that note continues to sound (indefinitely) even after I have released the key. If I play a different note, it will change accordingly but that note will now ring, and so on. I've played around with the various envelopes and decay settings to make sure it wasn't a 'user' error on my part and can't seem to get the issue to go away.

I'm guessing this is an issue with the gating circuit? Has anyone had a similar issue or have potential suggestions on troubleshooting this problem?

Thanks in advance!

[thealien666]

Most probably a keyboard gate contact coil spring issue.

[oliverrichmond67]

I also have the same problem and how to solve this.

[Stevie Ray]

Agree with thealien666. More likely to be a mechanical issue with a stuck keyboard contact rather than the gate circuit. Check the 'trig out' voltage (PL-1 pad 6) - it should be 0v with no key down and +10v with any key down.

Schematic can be found here...

http://www.fantasyjackpalance.com/fjp/s ... -schem.gif