[sdiy] TZ triangle core

[Ian Fritz]

At 12:42 PM 3/2/2011, David G. Dixon wrote:
>I haven't wrapped my head completely around what you're trying to do, but
>I'll tell you how I solved the problem with my own TZFM.  I simply fed the
>triangle through an optional inverter (an opamp with either +1 or -1 gain
>depending on the status of a n-channel JFET which shorts the + input when
>turned on) and drive the comparator/schmitt trigger with the output.  The
>polarity of the FM signal drives a comparator which determines the state of
>the JFET.  The nice thing about this circuit is that it doesn't require edge
>detection or anything like that, so it's actually failsafe (i.e., it will
>always go in the right direction).

I don't get it. Where does the modulation go, ie where is the multiplier?

Ian