[sdiy] VCO reset time for BBD-based PM

[Ian Fritz]

At 02:52 PM 6/2/2004, JH. wrote:
> > Hmm, a discharge of 300ns is 1/3000th of the cycle of a 1kHz. That would
> > mean that at 1kHz you're off by 0.3Hz and at 10khz you're off by 3Hz....
>
>I'd say that's ok - just so - for an audio VCO.
>
>But once you want to clock a BBD for making a Physical Modelling oscillator,
>it looks pretty bad. With a BBD length of 512 stages, you're already in the
>1ns
>range of reset time for the accuracy quoted above. Or use some compensation
>method and longer reset times.
>
>Re-introducing Harry's dreaded BBDs into the thread (;->)
>But I'm serious about this application. So who makes a HF VCO that goes
>up into the MHz range and keeps the tracking error in the ns range ??
>HF compensation allowed, PPLs not allowed.
>
>JH.

Maybe this would be a good place for the charge-balancing type of V-F 
converter?  Normally these are of limited use because the output is a 
narrow pulse, but could be OK for a clock.

   Ian