Give it shake!!!!! I was playing around and made this by accident. I was trying to make a different type of function generator, but it wouldn't keep going. The section on the right was going to make the sign wave but it would fade to zero after a short while. I added a comparator to make the square wave with a diode to inject a signal that would keep it going. What happened surprised me. The out put of the op amp became a sign wave when I added the diode.
