GB615446A - Improvements in or relating to electric discharge tube arrangements for operation atvery high frequencies - Google Patents

Abstract

615,446. Thermionic valves. PHILIPS LAMPS, Ltd. Dec. 6, 1945, No. 33015. Convention date, Nov. 14, 1940. [Class 39 (i)] The electrodes of a valve, particularly for ultra - high - frequencies, or their supports are sealed into the envelope by a glass seal of cellular structure consisting of at least 5 per cent of fine bubbles and having a specific gravity at least 5 per cent lower than that of the glass in a homogeneous condition, and are continued outside the envelope to form the elements of an oscillatory circuits. In the triode arrangement shown, the support wires of the grid 3 and the cylindrical anode 4 are sealed preferably without change of section through the cellular glass closure 5. Preferably, the indirectly-heated cathode 2 is sealed without change of section through the closure at the same time as the other electrodes and simultaneously with the closure of the envelope 1. The external oscillating circuit is formed by the extensions of the anode and grid supports, and the latter may be wound with a wire or may carry a metal tube 7 to equalize the internal and external capacity of the circuit. Tuning is effected by a slider 9. In modifications, the arrangement of the electrodes may be reversed, and may comprise one or more anodes surrounded by one or more cathodes. An arrangement for push-pull operation is referred to in which two grids and two anodes are disposed on either side of a common cathode. The cellular glass closure is used at both ends of the envelope, and the grids are sealed through one and the anodes through the other. Specifications 603,489, 604,245 and 615,477, [all in Group XXXVI], are referred to. The subjectmatter is identical with that of Specification 552,700.