Quadrature VCO Module finished

[Joachim Verghese]

> How does this quadrature part of the circuit work?  Is the OTA
> functioning as a second integrator?

I'm not sure if it would work, but I thought of a two-OTA state
variable filter with enough resonance to self-oscillate. Then the
band-pass output would be 90 deg out of phase with the low-pass
output. But I guess it's good for sine waves only, if it works
at all, that is. Just a thought.

-joachim