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Subject: Fine tune mod was: Background Info on MOTM VCO's??

From: "J. Larry Hendry" <jlarryh@...>
Date: 2002-08-17

----- Original Message -----
From: mmarsh100 <mmarsh@...>
I seem to remember a mod discussed that narrowed the range of the
FINE control. Was it Stooge Moe that discussed this?

BTW, even if you are not a builder, it's probably an easy part(s?)
replacement.

--LH--
The mod is simple. Once trace cut, one resistor. Changes the range from 11
semitones to 3 (or size the resistor for whatever you want)
Details: http://www.wiseguysynth.com/larry/mods/300mod.htm

And of course, Paul is 100% correct (as always, and as I have learned from
him) that the stability of fixed resistors is much better than trimmers.
While my 822 circuit is not perfect, one of the things I did was make the
trimmer a very small part of the overall resistance in the circuit. So, you
get the best possible performance by still having trimmers. It could have
been done almost without trimmers. But, that was about the best I could do
at the time. The replacement is actually on the drawing board. That may
happen if I ever run out of 822 PCBs (I still have plenty).

Larry