GB545445A - Improvements in electron discharge devices - Google Patents

Abstract

545,445. Electron discharge apparatus. MARCONI'S WIRELESS TELEGRAPH CO., Ltd. Nov. 22, 1940, No. 16807. Convention date, Nov. 24, 1939. [Class 39 (i)] An electron discharge device of the beam type comprises a substantially straight cathode 14, a cylindrical electrode 16 surrounding it and having a slot 161 parallel to. it, means such as rods 17 for forming a beam adapted to pass through the slot, means such as rods 18 between the cathode and the slot for deflecting the beam, an output electrode 19, and a pair of shielding and deflecting electrodes 20 on opposite sides of the beam.between the slot and the output electrode. In the form shown, the cathode is of rectangular section and is coated on its front face 15, and the plates 20 are of arcuate form. The device may be used for measuring the angle of phase displacement between two electrical oscillations, for controlling circuits in dependence on this angle, for maintaining specified conditions governed by it, and it can also be used for frequency multiplication. For the first purpose, one of the alternating voltages is applied across the electrodes 18 and the other across the deflecting plates 20. The electrodes 18 deflect the beam to and fro across the slot 16<SP>1</SP> ,the beam passing intermittently through the slot only at such times as its deflection is substantially zero. The intermittent beam passing the slot is deflected by the plates 20. Should the alternating voltage applied to them be in phase with that applied to the electrodes 18 the deflecting field close to them will be zero at the moment the beam passes them, and it will be undeflected; should, however, there be a difference of phase the beam will be deflected proportionately to it. The electrode may be formed as a fluorescent screen to indicate this deflection. Fig. 6 shows a modification in which three electrodes 25, 26, 27 are employed, connected so that in in-phase conditions only the circuit 41 is energized, whilst under out of phase conditions a push-pull circuit 40 is energized. By connecting both the electrodes 25, 26 to the same side of the transformer two impulses are in the same direction and applied to it for each cycle of the applied voltage, resulting in frequency doubling. In another form, one output electrode is formed with one or more slots parallel to the slot 16<SP>1</SP>, behind each of which is a further electrode. A further form comprises an output electrode in the same cylindrical surface as the deflecting plates 20 and a second electrode outside it which covers the gaps between it and the plates 20.