(FWD) Help with turning "+ CV" into "-CV"

[media at mail1.nai.net]

Someone posted this to another list.  If anyone here has an answer, I'll
forward it back to him.

From: Plutonique9 <Plutonique9 at symbiocom.com>
To: <Analogue at hyperreal.org>
Date: Tue, 19 Dec 2000 06:21:36 GMT

I'm working on CV inputs for VCF and VCA on my CS01. I've added the
inputs for the CV yet there is a slight "CV format" incompatibility.
The VCF and the VCA respond to CV from 0 volts to -5 volts.
So basically I need to rig up a circuit that will turn a regular
positive voltage CV source (such as an LFO) into a negative voltage
CV. I've been checking out schematics for Op Amp inverters, but I'm
not sure if that is what i am supposed to build. Can anyone confirm
whether this schematic will suit my application, this is supposed to
invert the phase 180 degrees, but I'm not sure whether it will invert
the polarity??????

http://www.eatel.net/~amptech/elecdisc/opamp4.gif

Maybe this is more a synth DIY question, but I'm not subscribed there
yet
-- Plutonique9, Plutonique9 at symbiocom.com on 12/19/2000