Phaseshift / Osc Sync idea

[Harry Bissell]

I'm not sure I understand the idea... The wave that is sync will not be of the
same shape as the original wave, it would be cut off, or reverse direction
prematurely (or similar distortion depending on what sync is used). I guess
you mean to send the same control voltage to both oscillators, so they run at
the same nominal frequency. Then take the PWM out of one and use it to sync
the second? I don't think the result will be two waves with selectable phase
(just one normal and one distorted wave).
Maybe this might be possible if you used a third oscillator to generate a
pulse at (let's say) the reset of the ramp, and a second pulse at some other
voltage level (like PWM comparator does). These two pulses will have vbariable
phase shift between them. Then sync two VCOs, one to each pulse. Run the same
CV to each (same frequency). That might give the effect you describe (but I'm
not sure). There is no reason you can't sync from any kind of waveform you
wany to. I'm still not sure I believe your idea (2VCO)or even my (3VCO)idea.
If anybody tries it (I don't have enough VCO's) let us know if it works.  :-) 
Harry Bissell

owner-synth-diy at mailhost.bpa.nl wrote:
I got this idea on phaseshift by using osc sync which I simply has to
bring up here.

In short: A slave osc syncs to the inverted output of the master osc's
PWM-stage. What we get (if it works and I cannot see why it shouldn't) is
two oscillators in sync where the slave is phase shifted as much as the
master osc's PWM output is shifted.

OK, but why?
By using CV on the PWM-stage we get CV-able phase shift between the
oscillators. Since there's no delay line or filter involved to do the
phase shift both oscillators should repond at the precisley the same time
to freq modulation even at audiorange modulation. Route any non-square
wave output from the oscillators to the CV-PWM input of the master osc and
you should get some sort of
waveshaping thing.

I guess this is already used somewhere but is it possible to sync on a
squarewave and not on a saw?

---Per


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