GB187202A - Improvements in and relating to thermionic tubes - Google Patents

Abstract

187,202. Habann, E. Oct. 14, 1921, [Convention date]. Addition to 182,105. Vacuum tubes.-A constant electric field, counteracting a constant-magnetic field to produce a negative resistance, as described in the parent Specification, is now produced by an auxiliary electron discharge, which crosses the main discharge. As shown in Fig. 1, the auxiliary discharge is produced between a cathode 14 and an anode 4 in a path at right angles to the path of the main discharge between a cathode and an anode 2. Each cathode may be surrounded by a grid 3, 15 maintained at a positive potential. The magnetic field is produced by means of an electromagnet 5. One or both of the anodes may be arranged edgewise to the corresponding discharge, so that the two electron paths intersect at a defined line. The circuit arrangement shown, having an oscillatory circuit 6 and a battery 7 between the cathode and anode, may be used for generating oscillations, and, with a telephone receiver 18, the arrangement may be used for heterodyne reception. In another arrangement, Fig. 2, a coil 20, coupled with an antenna 19, is connected with the cathode 1, and through a condenser 21 shunted by a high resistance 22, with one of two controlling grids 23, 24, arranged one on each side of the grid 3; or the coil may be connected in a similar way with the auxiliary cathode 14 and with one of two grids 25, 26 controlling the auxiliary discharge. A similar arrangement may be used as a wireless transmitter, the low-frequency speaking-currents being led through a transformer to a cathode and a controlling grid.