113 VCO and Wave Shaper

Description

This module is a VCO based on the triangle core SSI2131 chip, which provides an accurate triangle wavform even at low frequencies. Sawtooth, pulse and sine waves have been generated by this core which can be mixed and manipulated in the Waveshaper section.

The oscillator has both Coarse and Fine frequency controls, frequency modulationt and hard/soft sync. The VCO respons to 1V/octave keyboard input or can be set to LOW mode where it acts as a precision LFO.

Two of the four waveforms can be mixed using the pair of slide potentiometers, these composite waves are available as WAVEA and WAVEB. These two unique wave shapes can be switched between manually or via the GATE IN. They can be switched dynamically by the Zero Crossing Detector which is normalised to the VCO triangle waveform. Every time the detector loactes a zero crossing the MIX OUT is switched from one wave to the other. .