GB944577A - Improvements in or relating to m-type travelling wave tubes - Google Patents

Abstract

944,577. Travelling-wave tubes. M-O VALVE CO. Ltd., and B. J. HAMAK. May 8, 1962 [May 17, 1961], No. 18052/61. Heading H1D. In an M type travelling wave tube of the kind in which the interaction space is arcuate in form, the delay device 11, 13, Fig. 2, and the sole electrode 3 being respectively in the form of two coaxial structures with the delay device 11, 13 constituting the outer of the two structures the sole 3 is in the form of at least the major part of a ring and is mounted around a first support structure 23 made of ceramic material of high thermal conductivity in such a manner that the sole 3 is in good thermal contact with the first support structure 23 over at least the major part of its inner periphery, the first support structure 23 being mounted on a second support structure 19 which is in electrical and good thermal contact with the delay device 11, 13, the arrangement being such that the sole 3 is in good thermal connection with the delay device via the first support structure 23 but is electrically insulated from the delay device by means of the first support structure 23, and the travelling wave tube including means for cooling the delay device. The first support structure 23 is an alumina magnesia or beryllia based ceramic which is metallised and brazed to sole 3 and to cup 19. The delay line is interdigitated. The cup 19 is located within the end plate 12 by conical surfaces 20, 21. An annular water cooling channel 25 is used for cooling the delay line 11, 13 the water can also flow over the internal surface of the sole 3. The sole 3 is grooved to reduce secondary emission. The device preferably operates as a backward wave oscillator having an output coaxial line at the gun end and some teeth at the opposite end being coated with loss material. Specification 944,576 is referred to.