[sdiy] VCO Pondering...

[James Patchell]

That VCO cannot easily be made exponential.  That one is a true VCO, in 
that voltage controls the frequency.  What we normally call VCO's are 
actually CCO's (current controlled oscilators).  The exponential converters 
we use output a current that is used to control the frequency.  It is a 
fairly nice oscilator, all things considered.  I used one of those (or a 
similar one) in my first synthesizer....

At 01:23 AM 6/24/2004 -0500, Pat Kammerer wrote:
>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".

         -Jim
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