My Micromoog has an apparent problem wherein when the modulation section is turned on, and the wheel is set at the lowest place there is still modulation happening. This is not acceptable. When it is at the lowest setting the mod wheel should not have any apparent modulations. It should only happen when the wheel is turned up. I suppose it is possible that the pot that the wheel turns somehow slipped on the wheel and I need to re-set it, or is there a trim pot somewhere in the mod section that I can turn to get it to “zero out” when the mod wheel is turned down (in the "rolled forward-most position)?
Thanks! Another small problem I think may be happening is there seems to be a small amount of bleed through on the synth when no key is depressed, a faint oscillator tone is still heard. Thanks for any ideas or comments regarding these two things!
This should be an easy fix. There are trim pots accessible from the back, there are a few holes about the size of a small screwdriver (hint hint you’ll need a small screwdriver) the modulation amount is labled trill. Use a small flat screwdriver and gently turn the trimpot, with the mod wheel all the way down, until you no longer hear modulation. Then for the oscillator bleed, you will want to turn the trim pot labeled vca balance. Pretty much same deal, set the vca envelope at 0, move the switch short decay and adjust the trim pot until there is no more bleeding. Make sure that you don’t apply to much downforce with the screwdriver. There is not much supporting them plus its old and can be fragile. This should fix your problems. Let me know how it works out.
Do you have a manual? If not I could try and scan it and email it to you. Its a good read.
Yes I have a Service manual. Thanks. I will follow the procedure as specified in manual and your post above. Thank you! I’ll post results..
As nicely as I can put it, this advice is completely wrong.
The trill adjustment adjusts a musical interval when the square wave is used as modulation.
It adjusts the lower interval’s offset amount. (the lower portion of a squarewave) so that imparting modulation doesn’t change the base pitch of the oscillator.
The VCA balance is for adjusting.. well, VCA balance.
It has nothing to do with bleedthru at all.
It only affects DC offset (thump.)
The adjustment for the wheel is actually the wheel’s setscrew.
There are no trimmers to adjust the wheel’s minimum modulation amount or bleedthru.
This is clearly explained in the service manual.
It IS a good read. 
my bad, sorry. Maybe I should check my resources before giving advice…or just keep my mouth and let the techs handle the technical questions lol. Glad your where here kevin to set me straight.
TOO LATE!
…Just kidding !..
Thanks Kevin.. Maybe I’ll crack the book open.. Dust collecting on it, etc..
Actually it is on pdf.. But anyway, any ideas on the bleedthrough problem?
And, on the trill adjustment, are you saying the lower note on the square wave modulation is supposed to be the original note of the oscillator? Thanks
I probably moved the mod wheel off its original setting on the pot when I pulled the mod section to check the pitch bend ribbon.
OK I looked under the mod wheel “hood” and as it turns out, it wasn’t the mod wheel adjustment. Similarly to the problem with the pitch bend ribbon, there were more loose solder joints on the board (next to the contacts for the pitch bend ribbon). So I sprayed the contacts and heated the solder joints and the mod wheel works like a champ!
Also there was a slight change in the oscillator bleed-through when I just moved the keyboard base board around from the top panel. So I looked at the connection between the keyboard and the boards and moved it around.. Apparently there was a grounding issue or maybe the wires were emitting or picking up radio waves and causing them to generate a bleed-through on the trigger voltage–I don’t know–but when I put the connections between the boards and the top panel, the osc bleed-through went away.
Thanks for the forum, thanks Kevin for all the commentary and advice..