GB1253466A - Microwave electron tubes embodying slow-wave circuits - Google Patents

Abstract

1,253,466. Velocity-modulated tubes. VARIAN ASSOCIATES. 30 June, 1969, No. 32998/69. Heading HID. In a travelling-wave tube having a centipede slow-wave structure-i.e. a coupled resonator structure formed by a sequence of discs axially spaced along a conductive tube, each disc being centrally apertured to permit passage of the electron beam, and having an array of peripherally spaced, radially directed legs, adjacent ones of which are of S-shape and reverse-S- shape respectively-broad-band coupling to an output waveguide is achieved by the use of a transition section of ridged waveguide. The transition section 6 is formed by a length of rectangular waveguide with a ridge 23 projecting towards the output end of the centipede structure from the opposed broad wall of the guide. Both the waveguide and its ridge are tapered, as shown, over a distance of about 2#. A hollow conductive post 24 coaxial with the electron beam and leading into the collector 4 projects from the waveguide ridge into a wave-energy coupling hole 25 formed in the opposite broad face of the guide which closes the output end of the centipede structure. Hole 25 is oval in shape, with its major axis extending perpendidicular to the narrow walls of the guide 6. The. centipede structure may be severed, and may be preceded by a multi-cavity, stagger-tuned klystron input section.