The printing telegraph signal normalizer

The military type AN/FGC-5 time-division multiplex (TDM) is provided with a stop-start operated input distributor for each channel. This distributor can accept a teletype signal that arrives at any arbitrary instant of time. Storage cells are provided to store the selection elements of each character until they are transmitted out of storage at the proper time in the multiplex cycle by the output distributor of the transmitting multiplex. Whenever there is no complete character in storage tor transmission, the resulting multiplex signal for that channel causes the receiving multiplex terminal to deliver, to the receiving teleprinter equipnent, a marking stop signal during the period of one multiplex cycle (a "rest signal"). If no teletype signals enter the input distributor of the transmitting multiplex for an indefinite period, the receiving teleprinter equipment receives from the multiplex an indefinite sequence of rest signals, that is, a continuous marking stop signal that has a total duration equal to some whole number of multiplex cycles. Further details of the operating principles of the Printing Telegraph Signal Normalizer can be found in US Patent No. 2,721,230 issued 18 October 1955.