RA Moog power supply calibration, help!

The Moog Forum Moog Music General Topics Forum
1

For my first ever electronics project, I replaced all wet caps and damaged polyester caps on my early moog…and, guess what? It plays like a charm.

But I want to get the power supply just right…and so far the best I get is:

+10.02 and -9.99 V

But I have no more room to work with on the wirewound trimmers and can’t get any closer than this.

What are my options? The trimmers seem to behave just fine (I hear they deteriorate however) but replacements are impossible to find.

Any advice on how to fix this? I have seen earlier discussions of replacing the trimmers…but can I change something else, like a resistor?

Just so you know I replaced the original 500uf caps on the rectifier board with 470uf…but I am rapidly getting outside my depth in terms of diagnostics.

Thanks for any help you can offer.

2

Cant help you, but your a brave man. Succes

3

0.01v deviation is more than close enough.

Wirewound trimpots aren’t continuous, they actually have fine steps.

You’re good.

4

FWIW, one of the trim adjustments on my Mini for the positive 10v is almost at the end of its travel in order to get +9.98 volts. if I move it more, it results in +10.02 volts. Impossible to get exactly +10.00 volts, at least on mine. Everything under 0.10 volt deviation from the target voltage is negligible as long as that voltage is stable IMHO.