This Module is currently available.
Voltage Controlled Oscillator
FUNCTION DESCRIPTION
The SW901 Voltage-Controlled Oscillator is a widerange generator of repetitive waveforms, the frequency of which is controlled by the sum of applied control voltages. The total frequency span of the oscillator is 0,1 to 15.000 Hz in six overlapping ranges. Four waveform outputs are available: sawtooth, triangular, sine and pulse. The width of the pulse waveform is continuously variable, by means of a front panel potentiometer, from complete symmetry to 8.1 asymmetry. One fixed and one variable output are available for each waveform.
This Module is based on the original design from 1964.
http://www.synth-werk.com/sw-901-voltage-controlled-oscillator.cfm