saw to sine

[WeAreAs1 at aol.com]

In a message dated 5/21/00 9:56:28 PM, you wrote:

<<How do I convert a sawtooth to a sinewave? 
The saw looks like this / / / / and comes from a 
Fatman vco.>>

The usual method is to first convert the saw to a triangle, using one of the 
several proven techniques, then convert the triangle to a sine with some 
nonlinear waveshaping, such as diode clipping or overdriving the input of a 
3080 ota.  Unfortunately, the Fatman 555-based VCO's don't really provide a 
perfectly shaped sawtooth wave, so they don't lend themselves very well to 
the usual saw-to-triangle methods, most of which rely on a very uniform and 
linear ramp with a sharp fallback, in order to work correctly.  It's probably 
worth some experimenting, though.  There are several saw-to-triangle circuits 
out there among the various DIY websites.  Maybe  someone knows the URL's?  
(I don't..)

Michael Bacich