Simple VCO Idea...

[tomg]

Hello MST. Something like this?

http://www.xavax.com/efm/cbook/pics/vco3f.gif

I like it when there's a nice coincidence. I've been working with this core
for a while now. New people need a simple vco to start with and the UJT
vco at my site is getting harder to build because of the dreaded "No longer
Available" syndrome. This is the latest simplified version of an old friend.

Tom



> I was thinking about working up a simple VCO, with  sync and at least a
> sawtooth w/f. I came up with an op-amp integrator whose output is run
through
> a comparator. The comparator output controls a N/O switch across the
> integrator's cap. How it works (I think...): when a CV is connected to the
> integrator's input,  the int. output falls --assuming that the CV is
> positive-- until the output causes the comparator to go high and the
switch
> across the cap to close, resetting the integrator for another go. and
> another, and another, and another.... You can sync the VCO by routing an
> external spike signal into the control input of the switch.
>
> This seems to me to be uncomfortably simple to be particularly effective.
Has
> anyone tried to do something like this before?
>
> MST
>
>