[sdiy] hard and soft sync implementation

[Rob]

Just wondering how this is implemented and what the theories of
implementation are.

I am trying to do it with a FR777 tb303 cco type vcos. I have implemented a
type of soft sync that changes the sync amount by varying the pulse amp from
the trig pulse of vco 1 to the unused input of the opamp of vco 2 . It
works, but I am trying to stop it from somehow feeding back the trigger into
osc 1.. I am getting wierd but kind of cool interactions! Somewhat like a
ring-mod in sound. I guess a diode would take care of that, but maybe
someone knows of a better idea?

Rob