GB639395A - High frequency electron discharge apparatus - Google Patents

Abstract

639,395. High-frequency discharge apparatus. STANDARD TELEPHONES & CABLES, Ltd. July 6, 1946, No. 20243. Convention date, Aug. 23, 1945. [Class 39 (i)] [Also in Group XL (c)] In a high-frequency electron discharge apparatus, a first cavity resonator 18 is effectively connected between the cathode C and the control grid G1 of a thermionic valve having a positively-biassed control grid G<1> and a retardation electrode G<2> between the control grid and the anode P. A further cavity resonator 3 tuned to the same frequency is connected between the anode and the cathode, the D.C. potentials on the electrodes being such that when the control grid G1 swings positive due to the field in the first resonator 18, electrons are drawn through the retardation electrode G2 to impinge upon the anode, thereby exciting the further resonator 3, while when it swings negative, electrons are returned towards the cathode. The first three electrodes may operate so as to tend to produce Barkhauser-Kurz oscillations type, but the D.C. potential of the control grid is preferably adjusted to prevent such oscillation, R.F. energy being fed into the exciting resonator 18. A current regulating grid G3 prevents operation with the cathode emission saturated, and forms the effective cathode. An additional resonator 19 is provided between the control grid G1 and the retardation electrode G2, and the R.F. input is introduced symmetrically into the resonators 18, 19 by means of balanced loops 24, 25. The R.F. output is taken off by the loop 10 in the resonator 3, when the apparatus is operated as an amplifier. The apparatus may be operated as -an oscillator by the provision of feed-back between the resonators 3 and 18.