Control is done by means of an RS-232C connection to a four pin RJ11 modular jack on the back of the unit (an adapter to a standard DB9 connector is supplied by Broadcast Tools with the unit). Serial port parameters should be set to 9600 baud rate, no parity, 8 data bits, 1 stop bit, CR/LF termination.

The SS 12.4 should be configured to use 'Mix' mode. This can be done by setting DIP switches SW1-7 and SW-1-3 to OFF.

Operation in 'multidrop' mode is not supported.