Arduino-based FM VCO

Here’s another module I based on HAGIWO’s design. It’s an FM VCO with two operators: a carrier frequency and a modulation frequency. It uses the Arduino Mozzi library.

It works with 1V/Oct CV sources, but with a limited range.

Demo 1:

Demo 2:

You can also check out HAGIWO’s demo on Youtube.


The original schematics and code I used for this is from HAGIWO’s blog. The diodes I used were BAT41 and the OpAmp was TL072.