GB483888A - Improvements in or relating to electron discharge tubes for use for ultra-short waveradiation - Google Patents

Abstract

483,888. Electron oscillators; directive wireless signalling. TELEFUNKEN GES. FUR DRAHTLOSE TELEGRAPHIE. May 6, 1937, No. 13012. Convention date, May 6, 1936. [Classes 39 (i) and 40 (v)] In an electron-discharge tube used for direct ultra-short-wave radiation a number of anodes A1, A2, A3, Fig. 1, are provided, these also forming a multiple dipole aerial system; the anodes are excited by electrons oscillating within the tube between an indirectly heated cathode K and a retarding electrode B. Only portions S, S1 of the cathode have emitting coating. The anodes are coupled together by a single or double wiring L, to determine the phase relationships between the anodes and to enable a biassing potential to be applied to the anodes. A reflecting electrode R, Fig. 2, may be placed to one side of the anodes to concentrate radiation to one side of the tube. Filamentary cathodes K1, K2, K3, Fig. 3, which may be divided as shown at K3, K<1>3, may be used ; the filaments are opposite the anodes and may be housed in slots in a shield F at cathode potential or placed in front of such a shield. The shield may have concave reflecting parts about the filaments. In place of thermionic cathodes, the cathode K and plate B may both be capable of secondary emission, the potential of the anodes maintaining the electron cloud in to-and-fro osciltation. A " fir tree " aerial is shown in Fig. 6 made up of a number of dipole anodes A1, A<1>1 . . . . A12, A<1>12 suitably connected by wiring L, which is also used for biasaing.