[sdiy] sync circuit woes

[Simon Brouwer]

David G. Dixon schreef:
>>Then why is the 22p in a positive feedback loop?  (It's there to hold the
>>discharge pulse on long enough to totally drain the cap.)
>
> Oops.  I stand corrected.  Still, is the value of this cap all that
> critical?  Also, would it be necessary at all if an opamp had been used as
> a
> comparator here instead of the LM311?

Yes and yes.

If this capacitor is too small the sawtooth will not be completely reset,
so that its amplitude is decreased and its frequency will be too high.
If the capacitor is too big the duration of the reset will be too long so
that the sawtooth shape is affected and the high notes will be flat.

-- 
Vriendelijke groet,

Simon Brouwer
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