The 'One-of-three' VCO
An excellent sounding and popular VCO (voltage controlled oscillator) module. The design was originally inspired by the classic sound of the Mini's VCOs with the central core of the oscillator being somewhat similar. However, a great many things have been added and changed to make it more suitable for a modern modular system.
Four output waveforms are provided simultaneously; falling ramp sawtooth, triangle, pulse and sinewave. Output levels are 10V peak to peak, in common with most modular systems.
Apart from the usual fixed 1V/octave modulation input, a fully variable exponential input is available as well as a fully variable linear modulation input.
Slave synchronisation is easily obtained by inserting a falling sawtooth waveform into the SYNC input. This input is level sensitive to allow different strengths of synchronisation. A front panel pot is provided to control the depth of the effect.
The pulse waveform can be modulated in two ways. You can have either 'centred' or 'edge' modulation styles. The former will modulate both edges of the pulse output. The latter modulates only one edge. This can have a profound effect on audio rate PWM. The selection is implemented by a simple switch on the front panel.
The pulse output features a useful method of maintaining average output level. This means that fast sweeps of pulse width no longer produce any audible clicks as they do on other VCOs you may have used.
Power (+/-15V) is provided to the board either by standard Oakley 4-way header or Synthesizers.com header. Current consumption is approximately 35mA per rail.
Available as an assembled Module and as a DIY project.
No info about availability.$358 submitted Oct 26th 2012, 10:03 by Squiggletronics | last Change Oct 22nd 2015, 17:11 by Coorec