That's the Paper Bit version of the Chua's circuit. The Chua's oscillator board can be controlled by voltage. It makes great chaotic noise, has two different outputs and two frequency range.
The PB705 VCCC Voltage Controlled Chua Circuit was designed by Wolfgang Spahn, 2017-20.
It is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License.