[sdiy] linearize OTA for VCF?

[Jim Patchell]

    The best (clearest) drawing I have is at
http://www.silcom.com/~patchell/jp2rest/dualvco.pdf

    There is only 1 LM13700 on the page, so, it is pretty easy to
locate.  I used a CA3046 for the current sources, and they also double
as the inputs.

    -Jim


jhaible at t-online.de wrote:

> >     Hmm....I used current sources to run the diodes on a
> > 13700 and I thought I
> > didn't have any problem...maybe I better go back and take
> > a look.
>
> Which resistors did you replace ?
> Replacing *all* resistors with current sources *must* work.
> Replacing the two resistors to GND (lowest value, thus
> least ideal current source approximation) with current
> sources shows the mentioned, undesired effect.
>
> JH.