[sdiy] VCO Pondering...

[Pat Kammerer]

I'm assuming that the VCO on page 13 of this datasheet is linear;
http://pubpages.unh.edu/~aperkins/pdf/LM-devices/LM339.pdf

If it components were chosen for the audio range (close as possible), and a
good exponential converter was added to the input, would this make an
acceptable VCO?  Also, how difficult would it be to add hard/soft sync and
PWM?

These questions are kind of intended to be a general query about all of the
overly simple VCO circuit that you find "out there".