That's an analog controlled junction board for the analog computer Confetti.

The Analog Junction should be connected to the input of a Pop Neuron. That signal is a triangle wave and can control for example a crossmodulation.

It uses two H11F1 optocoupler for controlling two output resistors. One has to trim the two potentiometer for a wide range of the output resistor. The measure points are marked on the board. On poti is for the attenuation, the voltage should be peak to peak 6V. The second one rises the voltage level. The minimum voltage should be 3V. After triming the potis the signal that goes in the optocoupler should be between 3 and 9V.

The board will interrupt the bus.

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