VCOFan 1B

Eurorack Voltage Controlled Fan Oscillator

Overview:

The VCOFan is VCO that uses a fan as a sounds source. There is a LED under the fan that shines onto the blades of the fan, the fans bottom side is spray painted white, so the light from the led reflects from the blades. Next to the led there is a LDR that translates the reflected light into a voltage, which is the audio signal.

Connections:

The top connector is the CV input for the Fan speed (0v to 12v). The middle connector is the CV input for the LED brightness (0v to 12v). The output is the bottom connector, it is a audio signal that is capacitor coupled.

Potentiometers:

The top potentiometer sets or attenuates the Fan speed. The middle potentiometer sets or attenuates the LED brightness. The bottom trimmer potentiometer (under the 2mm hole) sets the audio output volume.

Mounting:

It is best to mount the manual standing, the VCOFan will have a higher frequency range, because of mechanical friction. It will also make less mechanical sound this way.

Power:

It uses 10 pin IDC connector, there is a indication on the PCB where the red line (-12v) should go. the indication is the text "RED". Only the GND and +12v connections are used.
It uses about 30ma when the LED is off and the fan is standing still.
It uses about 40ma when the LED is full on and the fan is standing still.
It uses about 120ma when the LED is full on and the fan is at top speed.
It can use more power when the fan is speeding up from standing still to top speed.
Be careful not to stick stuff into the fan blades, then it will use more power and fan blades can break off.

http://gieskes.nl/eurorack/?file=vco-fan