a few newbie questions about my new old minimoog model d

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1

hey.
i recently got a minimoog model d from a friend who himself got it by accident and never used it.
sadly i have some problems with it which i cannot solve by myself.
so i thought, that maybe one of you might have some fun trying to solve them :slight_smile:

i managed to tune the scale, range and octave range for osc1 and osc2, but i am unable to get the range of osc2 big enough to fit 3oct.
i also recognized, that osc2 is a little less loud than the others.
i have a sequencer that gives out cv. when i apply it to my moog, the moog pitches up a semitone. cv then works fine i guess.
it played the sequence i programmed from the pitch of the key i held down. but after 10-20 mins the pitch went all over the place.
i got scared and unplugged the moog. after replugging it worked fine again for like 30secs, then the same thing happened. i never tried it again from there on.
but now from time to time the pitch is ra(n)ging like the first time i plugged a cv. i then off/on the moog and its gone.

i then tried to measure the voltage as told in the manual yesterday. after much reading i was 99% sure that i know where pins a1 a2 a3 are located on the osc-board.
but when i try to measure the +10v/-10v it only gives me 0.3v/0.7v! this really makes me afraid to try any more fixing by myself until i can be sure i dont make it worse.

i also have a professional synth-repair store nearby. but im hesitating to spend to much money there since the minimoog isnt mine,
and i dont really know if or when i have to give it back:) (the store is pretty expensive and not willing to give to many informations)

any advice on how i should handle my situation is very appreciated. hope i didnt forget to mention anything important.

best thanks

vraniel

2

The Mini wouldn’t be running on 0.3/0.7v. You’re not getting an accurate measurement.

It sounds like you have a leaky capacitor (or more than one) somewhere in the osc control that’s effecting the pitch sporadically. It’s very common, and tons of people sell capacitor kits for all sorts of different synth models on ebay.

You might be able to find the bad cap, or you could just replace all of them. I wouldn’t do it yourself though unless you’re very confident about your soldering and de-soldering skills. It would be a real shame to damage a Mini for the sake of saving a hundred dollars or whatever.

I don’t think they should charge very much more than that for changing a capacitor and possibly tuning up the Mini. It shouldn’t take a professional more than an hour I wouldn’t think.