GB423583A - Improvements in television relaxation oscillation generator systems - Google Patents

Abstract

423,583. Valve generating circuits; discharge apparatus. RADIOAKT.-GES. D. S. LOEWE, 10, Wiesenweg, Steglitz, and SCHLESINGER, K., 39, Friedrichstrasse, Friedrichshagen, both in Berlin. May 1, 1933, No. 12576. Convention date, May 2, 1932. [Classes 39 (i) and 40 (v)] In a relaxation oscillation-generator for television purposes employing a grid-controlled discharge device 1 for discharging the condenser 5, variation in the extinction potential is prevented by the provision in the grid circuit of means which prevent grid current from flowing. In the form shown, in which the frequency of the relaxation oscillations is determined either by a synchronizing potential 9 injected into the grid circuit or by the circuit constants if the synchronizing potential fails, resistances 10 are provided to prevent flow of grid current. To determine the frequency of oscillation if the synchronizing - potential fails, the grid is connected to a condenser 12 which with the main condenser 5 forms a potential-divider across the supply 6, 7. A bias battery 8 in series with a resistance 10 is connected across this condenser 12. The Specification as open to inspection under Sect. 91 comprises also a description of the construction of a discharge device. The discharge device has a cathode 2, Fig. 3 (Cancelled) surrounded by a grid cylinder 3 having a tubular projection 5 through which the electrons pass out. The anode is in the form of a ring 4 which surrounds the projection 5. Constructional, details and dimensions are given. The filling may be argon, nitrogen or mercury at a pressure between 0À1 and 2 mm. The cathode has a basic layer composed of alkaline-earth metal oxide, e.g. barium oxide, which is then coated with an alkaline-earth metal such as barium, which may be applied by atomization. This subject-matter does not appear in the Specification as accepted.