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Subject: 1v/oct trimming: how does it work?

From: Jeffrey Pontius <jpont@...>
Date: 2002-08-11

I've assembled several kits where adjusting a trimpot is used to set a
1v/oct 'scale', which I've done by using a keyboard, Korg tuner, and
adjusting the trimpot until (usually, but not always) the octave pitches
on the tuner stabilize (say, at A). I'm sure most of you have done this.

I would appreciate a basic explanation of how adjusting the trimpot and
sending 1 volt jumps (from the keyboard) enables the circuit to
'stablize' at 1v/oct. To me, a trimpot is a small potentiometer, so I
assume that there is some component in a sub-circuit that is being
'permanently' changed.

Are the tolerances of components used critical to achieving a 'stable'
1v/oct?

Thanks [novice electronics module assembler], Jeff