[sdiy] Trapezoid oscillator, was: Dual oscillator cores?

[Donald Tillman]

   > Date: Thu, 22 Oct 2009 00:44:10 +0100
   > From: cheater cheater <cheater00 at gmail.com>
   > 
   > Basically as I understand it you are making it easier on yourself to
   > do FM in your dual core oscillator by doing something similar to
   > variation calculus (see http://en.wikipedia.org/wiki/Total_variation
   > ): spliting your function into two similar function, one which is
   > always either growing or constant and one which is always falling or
   > constant.

I don't see anything remotely like variation calculus going on.

I think I explained it pretty well in the first of the three articles:
   http://till.com/articles/QuadTrapVCO/discussion.html

Check out the section with the colorful state diagrams.

   > What exactly happens when a negative signal is routed into the FM
   > input? Does the currently active integrator start emptying
   > itself, or does the opposite integrator start integrating?

"Emptying itself"?  

It just integrates in the other direction.

  -- Don

-- 
Don Tillman
Palo Alto, California
don at till.com
http://www.till.com