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Option modules are installed, this jumper is not used. In TW operation, the
call signal always originates on channel A. In 4-Wire operation, the call
signal is not used.
16. 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)
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