This circuit is based on one published by Sprott ( Added some pots, output buffers and changed some component values to get it in line with typical synth standards.
Also can switch between nonlinear and linear feedback paths. The idea was to allow the circuit to double as a filter when linear feedback is selected. Actually it is a pretty poor filter, but a pretty good chaos generator. It can be interesting feeding it a CV causing the output to move in and out of chaotic regions.
Tried to get it to oscillate as slowly as possible, hence the 1uF caps. Chaos sounds like noise at audio rates, so is much better to use this module as a contol voltage generator. Ian Fritz gave a lot of help with this - thanks!! Sorry if the component values are a bit hard to read, should be okay. When I upgraded my design software, it deleted all my old files, so there was only this low-rez pdf left.
Chaos-Filter pdf (250kB)
Here's a vid of the circuit being tested: