GB1149591A - Improvements in high frequency electron discharge devices incorporating travelling wave tube sections - Google Patents

Abstract

1,149,591. Velocity - modulated tubes. VARIAN ASSOCIATES. 7 Sept., 1966 [13 Sept., 1965], No. 40041/66. Heading H1D. In a high frequency discharge tube incorporating a slow wave structure and a lossy attenuator member, the latter is sandwiched between a pair of spaced, conductive wall members, at least one of which forms a confining surface for a fluid coolant flow channel and is deformable by the pressure of the flowing coolant to maintain the attenuator member in position in the slow wave structure, whereby brazing of the attenuator to the slow wave structure may be dispensed with. In a travelling wave tube housing a clover leaf slow wave structure provided with a pair of adjacent sever sections 16, 17, Fig. 3, intermediate its ends, each sever section is provided with four discs 20, 21 of lossy material retained within, and in good mechanical and thermal contact with, recesses formed in the inwardly radially directed fingers (33<SP>1</SP>, Fig. 2, not shown) of the clover leaf structure by the pressure of the thin flexible sidewall 25 of the coolant channel 28 when coolant is passed through the latter. Various methods of interconnection of the coolant channels for the different lossy discs are described, and in an alternative embodiment (Fig. 4, not shown) single coolant channels are interposed between and apply pressure to the lossy discs of both of the sever sections 16 and 17. In a further embodiment (Figs. 5 to 9, not shown) the arrangement of lossy discs and coolant channels is interposed between the two sections of a hybrid tube having a stagger-tuned klystrondriver section followed by a travelling wave tube section. The lossy discs may be of loaded beryllium oxide or Forsterite ceramic, silicon carbide, or carbon-loaded alumina ceramic, and at least the flexible wall portions of the coolant channels are of copper.