Doepfer's A-178 theremin module generates a variable control voltage by approaching/removing hand to/from an antenna. The distance range is about 30-40 cm. Additionally the module is equipped with a Gate output with adjustable threshold level. Controls/Inputs/Outputs: antenna input, offset (knob for zero adjust), 2 x CV out, 2 x LED (for CV control positive/negative and zero offset adjust) To simulate the original Theremin two A-178, a VCO (e.g. A-110) and a linear VCA (e.g. A-130 or A-132) are required. But of course the A-178 can be used to control other functions in the A-100 (e.g. filter frequency, modulation depth and/or speed, tempo, attack/decay time and so on). The CV output voltage of the A-178 can range - according to the setting of the front panel controls - from -10V...+10V. The gate output switches from 0V to about +10V.