GB488094A - Improvements in or relating to thermionic valves and thermionic valve circuit arrangements for use on short waves - Google Patents

Abstract

488,094. Electron oscillators ; valve generating circuits. TELEFUNKEN GES. FUR DRAHTLOSE TELEGRAPHIE. Nov. 28, 1936, No. 32661. Convention date, Nov. 30, 1935. [Classes 39 (i) and 40 (v)] Electronic oscillations are generated with high efficiency by directing a stream of electrons through a system of utilization electrodes in which charges are induced, the dimensions of these electrodes being so chosen in relation to the velocity of the electrons that the energy of translation of electrons entering the system in correct phase is practically entirely converted into energy of oscillation of the utilization electrodes, the electrons finally landing on a collecting electrode with negligible velocity. In one form the cathode K, Fig. 1, and concentrating electrode Z produce a beam of electrons which . passes through utilization electrodes A1 ... A6, electrons in correct phase being continuously retarded and fallng finally on the collector N. The electrodes A1 .. A6 decrease in size away from the cathode, to enable the times of flight of the retarded electrons through each electrode to be the same ; oscillating circuits LC are connected between the pairs of electrodes. In a modification, electrons from the guns K1, K2, Z, Fig. 2, are directed into a drum-like space between two semicircular utilization electrodes A1, A2 between which they pass to a central collector N in a spiral path of decreasing radius produced by a suitable magnetic field. Alternating voltages are induced in the circuit LC. In another form, four electrodes similar to A1, A2 are arranged to form quadrants of a spiral cylinder into which are directed electrons from a peripheral cathode. The collecting electrodes are two discs placed on opposite sides of the centre of the spiral cylinder. The electrodes are connected alternately in pairs to opposite ends of a tuned circuit. The emission of electrons from the cathode may be controlled in the correct phase by control grids. Alternatively, electrons emitted at different times may be directed into different systems, as in the push-pull arrangement of Fig. 6, in which two electrode pairs All, A<1>2 and A <11>1, A<11>2 are disposed on opposite sides of a cathode K. Control grids G<1>z, G<11>z are connected to electrodes A<1>2, A<11>1 respectively ; electrons are, therefore, emitted alternately into each oscillation space as the phase of the voltages on the electrodes is correct for maintenance of oscillations. A double frequency is said to arise between collectors N<1>, N<11> which can be fortified by a suitable circuit L<1>, C<1> or suppressed by capacitative shortcircuits between them and the cathode. The Specification as open to inspection under Sect. 91 includes also the subject-matter of Specification 489,608, and contains, in addition, much theoretical discussion of the working of a four-anode magnetron and of an arrangement, Fig. 2 (Cancelled) (not shown), in which an electron travels under the action of a magnetic field in a cycloidal path between two parallel electrodes carrying an alternating potential difference. This subject-matter does not appear in the Specification as accepted.