The Multiplexer is a link in the transmission of data from both long rage radar and gap-filler radar sites to the SAGE System Central Computer. The Multiplexer receives any combination of inputs, up to six, from the AN/FST-1 or AN/FPS-14, and -18 Gap Fillers.
The gap filler outputs are interleaved with the output of a long-range radar site. The information is then transmitted over a single pair of telephone wires. Signals from the AN/FST-2 control the reading out and transmission of the store information.
Permission to transmit is alternated between the stored gap filler data and long-range radar output. This permits the use of only one pair of telephone lines instead of seven. Multiplexer operation can be remotely controlled from a distance up to 150 feet.