MODULE 2200 - VOLTAGE CONTROLLED OSCILLATOR

The 2200 Voltage Controlled Oscillator is a complete, four waveform, exponentially and linearly controlled oscillator with an output mixer. The upper three inputs are for frequency control. The uppermost is attenuable from 1V/Oct with exponential response; the center has AC coupled linear response with a maximum sensitivity of 20% per volt. The lowest input responds exponentially at precisely 1V/Oct. The keyboard switch will instantly connect either of two keyboards at exactly 1V/Oct.The oscillator’s initial frequency can be adjusted by the coarse control over more than ten octaves, while the fine adjustment with its four semitone range allows precise tuning.
The range switch shifts the oscillator initial frequency down ten octaves. The frequency can be swept, however, over the entire twenty octave range from 0.03Hz to 30kHz.
The PW control and the PWM input vary the duty cycle of the pulse waveform from 0% to 100%. Maximum sensitivity is 10%/volt.
The four upper output jacks give each of the waveforms at full level (10V peak-to-peak for sine, triangle, and pulse, 0 to +5V for sawtooth). The waveforms are phased ; the falling edge of the pulse waveform is varied by the pulse width voltage.
The output mixer enables the creation of waveforms with infinitely variable harmonic content. The mixer is inverting, allowing the oscillator to simultaneously produce any output waveform and its inverse for control purposes.
The sync switch allows phase-locking any oscillators in the system. Oscillators tuned to whole number ratios will lock if their sync switches connect them to the same sync bus. The range of pull is slightly less than a semi tone.
The sync input will force the sawtooth to discharge, taking the other waveforms to their analogous locations, when a rapidly falling edge is applied.
The gate input synchronously turns the oscillator off when the input exceeds about +2.5V. As long as the high level is maintained, the sawtooth is not allowed to discharge, and rests slightly above +5 volts. As soon as the gate input is brought low, the discharge occurs, and the oscillator runs again. The gating and sync input features are not only useful in control oscillators at subaudio frequencies, but also produce interesting timbres when both the controlling and sync’d or gated oscillators are run at audio rates.