GB478095A - Improvements in or relating to electron amplifier discharge devices - Google Patents

Abstract

478,095. Cathode-ray tubes. TELEFUNKEN GES. FUR DRAHTLOSE TELEGRAPHIE. Feb. 26, 1937, No. 5850. Convention date, March 4, 1936. [Class 39 (i)] In an electron amplifier discharge device arrangement wherein an electron beam is subjected to longitudinal control, the controlled beam is projected through one or more hollow electrodes, which act as coupling-out electrodes for collecting energy contained in the density waves set up in the beam by the longitudinal control action, each of the electrodes being substantially equal to or less than #v/2c long, where #, v, c represent respectively the wavelength of the control frequency in space, the beam velocity and the velocity of light. The electron beam from a filament K is controlled by a Wehnelt cylinder Z which sets up rarefaction and compression waves in the beam. The latter in passing through the hollow electrode E induces charges thereon, and the current passing from the electrode is substantially proportional to the space charges located momentarily inside the electrode, which are again proportional to the control voltage applied to the cylinder Z. The length of the coupling-out electrode is preferably #v/2c# and there may be a number of such electrodes spaced along the beam, the distance between the middles of successive electrodes being #v/c. In a modification, two intermeshed coupling-out systems may be provided, by arranging a number of the electrodes along the beam and connecting alternate electrodes together to form two groups, so that the charges set up in one set of electrodes have opposite signs to those set up in the other set, thus producing a push-pull arrangement which can be connected to an oscillating circuit or the like.