Module A-146 (LFO 2) is a Low Frequency Oscillator, which produces periodic control voltages over a wide range of frequencies.
The LFO can be used as a modulation source for a series of modules (for instance pulse width and/or frequency modulation of a VCO, modulation of a VCF cut-off frequency, amplitude modulation with a VCA).
Three outputs are available, with different waveforms: sawtooth / triangle; square wave, and positive-voltage square wave.
The waveform is continuously adjustable from rising sawtooth, through triangle to falling sawtooth. The same control affects the pulse width of the square wave.
A three-way switch can select one of three frequency ranges, spanning from one cycle every few minutes, at the lowest, up to audio frequency at the highest. 

Width: 8 HP / 40.3 mm
Depth: 45 mm (measured from the rear side of the front panel)
Current: +20mA (+12V) / -20mA (-12V)