GB619958A - Improvements in or relating to radio transmitters - Google Patents

Abstract

619,958. Spark gaps. SUBMARINE SIGNAL CO. Feb. 25, 1946, Nos. 5781 and 5782. Convention dates, April 30, 1941, and Oct. 8, 1941. [Class 39 (i)] [Also in Group XL (c)] In an ultra-high frequency spark generator energized by the secondary 33, Fig. 6 of an aircored transformer 32, the transformer primary 34 is connected in series with a condenser C1, C2 or C3 and a resistor R1 ... R5, the circuit being triggered by a gas discharge tube 47 connected across a power source 46 and said resistor in series. The triggering voltage applied to the grid of tube 47 may be sinusoidal, peaked or sawtooth in wave form. The damping of the condenser discharge circuit is controlled by the series-connected variable resistance 43, to provide only one major oscillation, sufficient to cause breakdown of the oscillator spark circuit 57, 58. The main spark gap 22, 23, Fig. 1, is between two conical elements 20, 21, forming an oscillatory dipole radiator circuit and contained in a conducting cylinder 26 hollowed out to the shape of the cones 20, 21 so that the inner surfaces 27, 28 are spaced therefrom. The secondary winding 33 energizes the main spark gap through auxiliary spark gaps 16, 18 and 17, 19 and the spark gap equipment is contained in an air-tight chamber formed of the conducting casing 2 covered by a plate 4 of glass, ceramic &c. transparent to electromagnetic waves. A valve 3 allows air or gas to be pumped into the chamber under pressure. A horn 50 directs the radiation emerging through the plate 4. In a modification, Fig. 3, a single conical electrode 51 is supported in a conical shell 52 and carries a rod aerial 62, the spark gap being between member 51 and an adjustable screw 59 carried by shell 52. The gap adjustment may be viewed through a window 61. Specification 618,240 is referred to.