Intercom Line Connection: The KB-702 contains a 5-terminal plug-on connector for
intercom line connection. This connector is intended to be unplugged from the circuit
board when connecting the intercom line, and then plugged back on when the wiring is
completed. The connections for each pin are visible on the circuit board when the
connector is unplugged. The pinout of this connector is as follows:
Pin 1 --- (NC)
Pin 2 --- Channel A Audio
Pin 3 --- Channel B Audio
Pin 4 --- Power
Pin 5 --- Ground (Shield)