The EyeBall is a unique input device that is reminiscent of a Theremin, but is really so much more. It uses a photo transistor to sense varying light levels and convert them into analog and digital signals.
You can build one for less than $85
The EyeBall has two types of outputs, analog and digital which correspond to control voltages and gate signals.
Digital Outputs
- Pulse+
- Pulse-
- Toggle
Analog Outputs
- Normal
- Inverted
Controls
- Pulse Length From 70ms to 7sec (nominal)
- Offset Adjusts base level of analog outputs
- Level Adjusts the gain of the light amplifier
- Sensitivity Adjusts the sensitivity of the photo transistor
Indicators
- Pulse Yellow LED when pulse is active
- Toggle Green LED when Toggle output is HIGH
- Clip+ Red LED when Normal output is at +5V or above
- Clip- Blue LED when Normal output is at -5V or below
- Note that when the Normal output is clipping, the Inverted output will also be clipping but at the opposite polarity.
Eurorack Spec
- 17 HP width
- 3 U height
Video
Perhaps the best way to describe the EyeBall is to see it in action…
(This is an early prototype.)
Buy the Circuit Board and Front Panel
Price: $24.95
License Info
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