> > > So my question is, does anyone know of a two terminal circuit (plus
> > > power and control) that acts as a variable resistor where the
> > > resistance is set by a voltage level or a variable resistor with
> > > less current through it?

An audio filter I made once had an oscillator driving the control pin
of a 4066 switch. The effective resistance of the switch changed
by varying the mark:space ratio of the oscillator. More ON time =
lower resistance. The 4066 has a book value of 80 ohms, so that's
the minimum you'd get, and it can pass 25mA when fully on. Perhaps
you could try an experiment with a 4066 and a 555. You could
parallel the four switches in the package to lower the resistance and
get the current rating. As the switches are electrically isolated you
might not have a problem with that signal you want to pass. For that
matter, would an opto-transistor do, perhaps using a similar M:S type
system ? I don't think they make opto-FETs do they ?

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