[sdiy] Making a simple Relaxation oscillator into VCO

[Seb Francis]

I would guess that you replace the resistor in your RC oscillator with the current source .. but I might be wrong (it's a bit late at night!)

Should be quite an interesting sound .. kind of a curvey sawtooth waveform?

Seb



bill berzinskas wrote:

> Hey everyone..
>
> I've been working for a bit now with a simple opamp relaxation oscillator..  i'm starting to understand it, and figured i should move forth to making it more of a VCO..  can someone tell me how i would do this?   so far, i figure i need to actually control the pitch with a current change, and have made a voltage to current converter, but no matter where in the circuit i feed it in, it doesn't seem to make much difference on the scope..   can anyone help?!
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