GB764447A - A device for the distribution of electrical pulses - Google Patents

Abstract

764,447. Thermionic distributers. PINET, A. E. Jan. 21, 1955 ]Jan. 26, 1954], No. 1966/55. Class 40 (3). [Also in Group XL (c)] In a device for the distribution of electric pulses in a multiplex pulse transmission system the pulses are applied via an electron discharge tube to the input of a delay line which is shorted at its distant end and has its input end terminated in its characteristic impedance when a rectifier connected in series with a resistor across the input to the line is conducting. Pulses are tapped off along the delay line and connected to corresponding utilization circuits. The Figure shows a device for distributing electrical pulses to the channel modulators of a known type of multiplex pulse transmitter, the output from a control pulse generator 1 is applied via tube 2 to the input terminals 13<1>, 14 of a delay line 21 which is shorted across its distant end at 16. The negative-going pulses which are fed into the input of the line are n tapped off at points 13<1>, 13<2> ... 13 - and applied 2 n to the channel modulators 19<1>, 19<2> ... 19 - 2 to the input of which the signals to be multiplexed are also applied the outputs being connected in parallel to a transmission line 12. The negative pulses are reflected and have their plurality reversed at the short-circuited end 16 of the transmission line and are propagated back down the line as positive pulses and are finally absorbed in the circuit 17, 18 since the rectifier 8 conducts and the resistor 17 is equal to the characteristic impedance of the line. As the positive pulses pass down the line they are tapped off at points 13 n/2, 13 n/2 - 1 ... 131 and are applied by phase-reversing transn n formers 20 -, 20 - - 1 ... 20<1> to the channel 2 2 n n modulators 19 - + 1, 19 - + 2 ... 19n to the 2 2 input of which the signals to be time multiplexed are applied and the outputs of which are connected in parallel to transmission line 12. Thus by means of the invention a delay line having a length only half of that normally required is used.