[sdiy] Yusynth VCO

[Ian Fritz]

At 06:06 PM 4/3/2010, Neil Johnson wrote:
>Quite a few VCO designs do this - for example the Oberheim SEM has a
>similar arrangement.  It has the advantage of keeping an opamp out of
>the integrator with correspondingly faster reset time - you're left
>with a voltage buffer and a comparator (all discrete in the SEM).

True, but is the reset time really an issue?  My latest Saw design based on 
Terry's EN 62  resets in 200nS. One of the main innovations and advantage 
of Terry's design is that since the converter drives a virtual ground there 
are no issues with the Early effect.

But has anybody actually measured the tracking and stability of the Yusynth 
design?  It would be interesting to see some actual numbers.

Ian