[sdiy] YuSynth vco tracking

[David G. Dixon]

> Doing this subsequently in smaller steps makes it easier to achieve in
> practice, because if you make big adjustments you can easily
> overshoot.

<...snip...>

OK.  Perhaps I'll try it with my VCOs.  However, in my case, there will be
two adjustments: the summer gain trim and the HF gain trim.  What I've been
doing is starting at 1000Hz (which is within 3mV of the "nominal" frequency
at CV = 0V), assuming that this frequency is insensitive to any trim
settings (which is should be, since the CV summer should be generating 0V,
and this voltage feeds the HF inverter), then decreasing CV by 3V and using
the summer trim to achieve exactly 125.0Hz, then increasing CV by 6V and
adjusting the HF trim until the frequency is exactly 4000Hz.  Two points,
two trimmer adjustments: this makes sense to me.