Yeah, that's what I was thinking, too. Doesn't that make a passive
differentiator? Or do I have my terms screwed up...?
I remember seeing an op-amp circuit in an old Forest Mims book at Radio
Shack, years ago, that showed simple 3- or 4-component integrator &
differentiator circuits, and I thought that the differentiator pretty much
responded ONLY to changes in voltage, while an integrator RESISTED changes
in voltage.
Seems like AC coupling with a big cap or a differentiator circuit should do
the trick, no?
-----Original Message-----
From: Tony Allgood [mailto:
oakley@...]
Don't you just want a big cap? Something like 1uF non polar may do the
trick. Shove it inside a jack plug in series with the CV line. A bit
crude but it may just work....
Tony