BBSP is mixed kind of scanner especially designed for pedal controls in organ consoles. You can connect keys and potentiometers with just one board, and only one cable connected to master controller. Keys must have one pole of each contact connected to ground, that's typical setup in older organ consoles. Keyboard is connected using twor 16-pin IDCs. One connector covers 16 keys.
At the side there are 5 goldpins - this is analog portion of the board: 2 pins for connecting end taps of potentiometers, and 3 inputs for the pots' wipers. It can work with plain potentiometers, or voltages in range 0-5V. You may use dedicated cable with a plug to easy access those inputs without the need of soldering MIDI board directly.
As any other scanner board, this one cannot work just by itself, but it needs one of the master controllers to operate.
Here is connection diagram for contacts:
You may be interested also in the following products (click the image for more info):
5-wire cable with plug for analog inputs of BBSP
16-wire ribbon cable for contact inputs of BBSP
adjusting amplifier to achieve full (0-127) MIDI value change from fractional potentiometer rotation
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