varying capacitance to change pitch on mt-240

[synthmonger]

I've found that varying the pitch to a great degree is only possible by swapping capacitors. Ideally, I would like to make this variable via a potentiometer/vactrol so I can implement voltage control.



On a side note, has anyone found a way to add volume control to the drums/chords without using switches?

[liquidpaper]

there are such things as variable capacitors (just like potentiometers and photocells are variable resistors). i don't know what you could hack them out of. here's a link showing the kinds:

http://www.surplussales.com/Variables/AirVariables/AirVariableCapsIndex.html

[octatone]

DIY:

Cardboard and foil:
http://www.crystalradio.net/beginners3/cap.shtml

Or a little more classy:
http://www.eham.net/articles/5217

[blue hell]

Maybe also have a look here, for a solid state solution.

[liquidpaper]

you could also use a rotary switch and connect different capacitors to it.