GB485073A - Improvements in or relating to magnetrons - Google Patents

Abstract

485,073. Thermionic valves. TELEFUNKEN GES. FUR DRAHTLOSE TELEGRAPHIE. Aug. 10, 1937, Nos. 22017 and 22018. Convention dates, Aug. 17, 1936 and Aug. 20, 1936. [Class 39 (i)] In a split-anode magnetron having two concentric sets of electrodes the electrodes of the outer set are prevented from affecting the space within the inner set, either by screen electrodes, or by arranging that no part of them shall be opposite the gaps between the inner electrodes. In the arrangement shown in Fig. 2, the outer electrodes A1, A2 are connected to an output circuit N and the inner electrodes J1, J2 to a control circuit St. Opposite the gaps between the electrodes J1, J2, are screen electrodes Sch arranged so as not to interfere with electron paths represented by the dotted live E. The outer electrodes are given a positive bias by a battery Ua which gives the electrodes Sch a similar, but weaker, bias. In a modification, the electrodes Sch are replaced by louvre-shaped electrodes close to the gaps between the electrodes J1, J2. The electrodes Sch may, especially if the sets of working electrodes contain several members, be replaced by a grid or helical electrode. Fig. 4 shows the outer electrodes each formed in two parts A<1>1, A<11>1, A<1>2, A<11>2 connected together but having spaces between them opposite the gaps between the electrodes J1, J2. Electrodes Z having a positive bias greater than that of the electrodes A<1>, A<11>, A<1>2, A<11>2 are arranged outside to ensure a suitable distribution of the field. Fig. 6b shows the outer electrodes AR1, AR2 arranged radially. The electrodes for the control circuit St and the output circuit N are arranged at opposite ends of the tube. An arrangement with two such sets of radial electrodes, which may be connected for frequency doubling, is also described.