Adventures with the Tillman modulator (two L's in Tillman!)

[Don Tillman]

   From: "Tony Allgood" <oakley at techrepairs.freeserve.co.uk>
   Date: Mon, 31 Jan 2000 12:51:16 -0000

   I have just spent a fruitful weekend trying to get this variable duty
   cycled sawtooth circuit to work. I has abandoned my original current
   steering method, which was alright, but the frequency shift could not be
   easily compensated for. The key word is easily, it could be done, I'm
   sure, but with too much electronics for it to be practical for a VCLFO.
   So I went for Don Tilman's twin OTA circuit that takes the arithmetic
   minimum of two varying sawtooths. This indeed seems to show great
   promise.

Cool!  Thanks for trying it out.

Like I mentioned, the circuit is basically presented as something
you'd scribble on a napkin at a bar (but with suggested component
values!).  I'm sure it needs some tweaking to work.

  -- Don