The System80 820 Eurorack Oscillator is a utility Voltage Controlled Oscillator (VCO) based on the saw integrator and waveshapers common to many vintage Roland designs from the late 1970s. It features a discrete temperature compensated saw (ramp) core coupled to waveshaping circuitry that produces a pulse wave with adjustable width, a triangle wave and a sine wave. The conversion of the saw wave to a triangle wave produces a distinctive reset glitch at each peak. The triangle wave is bent by a diode shaper to produce an approximate sine wave.

Features

• Discrete Voltage Controlled Oscillator with temperature compensated exponential converter
• 1 V/octave tracking over 8+ octaves
• Sync input with weak and strong oscillator sync modes
• 1 V/octave CV input + one attenuated exponential CV input for pitch/frequency modulation
• Five position octave range switch
• Waveform outputs: Pulse, Ramp, Triangle, and Sine
• Pulse Width Modulation CV input

Open Source

820 is open source hardware. The design files are available on Github

http://system80.net/product/820/

• 10hp
• 15 mA +12V
• 15 mA -12V
• 0 mA 5V
• 30 mm deep