Double Deka Ultrasonic VCO

This unique VCO consists of an ultrasonic oscillator core followed by a parallel pair of waveform generators. Each waveform generator consists of a switched multi-octave divider followed by circuitry to generate a 10-step waveform using a set of 10 slider potentiometers. Also included are a novel synchronization circuit with two different operating modes and a built-in "digital ring modulator" (DRM) for producing a wide variety of synchronized and anharmonic sounds. The oscillator core is highly stable (better than 20 ppm/K in the prototype) and features wide-range, accurate tracking (better than 0.05% over fifteen octaves). The variable waveform generator provides fine control over an enormous range of available timbres.

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