2xLFO - With Difference Rectifier PCB | NonLinear Circuits

The dual LFO has two oscillators on board; these are based on the standard schmitt trigger/integrator design and give a square wave and triangle wave from each. The frequency ranges from 0.02 Hz (about 45 seconds per cycle) to 830 Hz; this can be changed by replacing the 1uF capacitors with larger values for slower rates or smaller values for faster. The triangle wave is 6V, ranging between -3V and +3V. The square wave is 10V, ranging from -5V to +5V.

There is also a Difference Rectifier circuit on the PCB which takes the triangle waves and supplies a signal that is the difference between them. This voltage is then delivered to the appropriate positive or negative outputs, basically a nice complex signal.