BLM JPJFET VCO
MODEL: BLM JPJFET VCO
Analog Saw Core VCO
Depth: 1 Stack PCB. Skiff Compatible.
Current: -18mA, +32mA
Circuit type: Analog
What does this do?
This is an analog Voltage Control Oscillator that is Saw core based. It uses a JFET part inside to generate
the Saw wave. This is very similar to a famous Roland Vintage product, but this is using modern equivalent parts.
The 1V per Octave circuit is also not transistor based. It is using a modern VCA circuit for 1v/octave tracking.
The 1V/octave circuit is also using the recent Op Amp OPA1678. OPA1678 has 110db Noise Floor, and 0.0001% THD.
The power rail capacitors are Tantulum type, and the timing Capacitor is a 2% 4.7nF through hole film type.
0.1% Reference voltages were used for the tune and fine tune.
Wave Outputs: Saw wave, Pulse Wave. Both are operating from 0v. -5v/+5v (AC signal)
Pulse Wave has a Pulse Width Modulation input.
Saw Wave is static, and the PWM does not do anything to it.
Modulation Inputs: Linear, and Exponential.
1. Modulation with Attenuator. Exponential Type.
2. Linear with Attenuator.
3. 1V/Octave Direct Input.
Hard Sync Input.
This requires a Positive Square Wave.
Softer AC wave forms will do a very soft sync effect.