GB497637A - Improvements in or relating to electric signal pulse controlling circuits - Google Patents

Abstract

497,637. Television; wireless receiving apparatus ; thermionic distributers. PERCIVAL, W. S., and WHITE, E. L. C. March 18, 1937, No. 7941. [Classes 40 (iii) and 40 (v)] Controlling signals applied to one of two unidirectional conductors 1 with a common electrode 9 allow or prevent the passage of signals through the other. Normally, current through the diode 9, 4 makes the cathode 9 positive so that no current flows to the other anode 13 when signals are applied to terminals 6, 7. When signals are to be passed, a negative pulse is applied through terminals 2, 3 to the anode 4 and stops the current to it. Current is then able to flow to the anode 13 and the output is taken at terminals 11, 12. At the other times the terminals 2, 3 may be used as the output for the signal. According to modifications: the biassing potential of battery 5 is negative, and a pulse of greater positive magnitude applied to the terminals 2, 3 ; the resistance 8 is omitted, a resistance is inserted in the lead to the anode 13, the signal is applied to the terminals 11, 12, and the output taken from the terminals 6, 7, Fig. 2 (not shown). The circuit is used for obtaining an automatic gain controlling potential from the synchronizing signals in a television signal, Fig. 3 (not shown), in a thermionic distributer for multiple signalling as described in Specification 470,495, or for providing synchronizing signals in television. Specification 491,728 is referred to.