I have the opportunity to improve one of my previous designs.  The
particular block I want to improve is the audio volume control.  It uses a
JFET in a voltage divider configuration to attenuate an audio signal.
Input to the gate of the JFET is a variable voltage from a front panel
potentiometer.

This design has a lot of problems such as having to Select-At-Test the JFET
for the correct resistance range and the non-linearity of the JFET.  I've
looked at designs using  transconductance op-amps but they involve a lot
more parts to implement than I would like.  Also, I don't understand them
well enough to adapt them to my circuit. :-{

Does anyone have a good idea for a simple, reliable, repeatable voltage
controlled volume control element to replace the JFET?  It can be a "volume
control" chip or an op-amp with a few glue parts and maybe a MOSFET or BJT
or two.  Control voltage varies from 0 to +5VDC. Audio level to be
attenuated is in the 100mV - 1V (p-p) range.  Attenuation should be 35+ dB.

Thanks for any ideas.

--=20
Carey Fisher
--=20
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