LFO being FM-ed and AM-ed by its sub-LFO.
Module is composed of two low frequency oscillators. Left side controls the main LFO: big knob for base frequency (from 0 to 10Hz), middle left knob for waveform (smoothly variable from sine to triangle to square to noise to sine) and bottom left knob for symmetry/phase.
Secondary LFO is controlled on the right side, first knob for waveform, second for symmetry and bottom chicken head knob for frequency - oscillation frequency of secondary LFO is set as a ratio of main LFOs base frequency (in steps from 1:1 to 1:6).
Two knobs in the middle adjusts the amount of effect secondary LFO has on the main LFO. Upper knob controls frequency modulation, lower knob amplitude modulation (AM has bipolar control).
Lamps shows the output signal. There is a reset input that should restart/sync both oscillators.