GB726644A - Branching arrangements for electric pulse communication systems - Google Patents

Abstract

726,644. Pulse signalling. STANDARD TELEPHONES & CABLES, Ltd. Oct. 2,1953 (Nov. 12, 1952], No. 27067/53. Class 40 (5). At a junction station, having two-way paths to three or more terminal stations, each path carries a train of marker pulses and interleaved trains of channel pulses, the marker pulses on one incoming path being used to synchronize all the received channel pulse trains and to control means for assembling the pulse train transmitted to at least one terminal by selecting some channel pulses from those arriving from two or more other terminals. In the embodiment described, the radio transmitters 56, 55, 47 and 43 and receivers 79, 37, 84 and 75 at the junction station communicate respectively with the north, south, east and west terminals 16, 17, 1 and 2. The incoming pulse train 36 from receiver 37 is used as the master control train, the double marker pulse being separated therefrom in circuit 38 where it is converted into a control pulse 49 which is fed to a delay line 50 provided with tappings equal in number to the number of channels. As these are four interconnected paths at the junction, each transmitter is fed from a mixer connected to the outputs of three gate circuits by which pulses are selected from incoming pulse trains from the other three paths. The gating pulses are derived from selected tappings on line 50 through sets of bus-bars 51 ... 54. In order to ensure correct interleaving of all the pulse trains, a master source at each terminal station is synchronized by a marker pulse 71 supplied to all the transmitter mixers from a gate circuit 39 opened by a pulse 69 from the end tapping on line 50 to pass the marker pulse from pulse train 36.