| 摘要 |
952,338. Travelling wave tubes. STANDARD TELEPHONES & CABLES Ltd. June 8, 1960, No. 20062/60. Addition to 906,206. Heading H1D. In a travelling wave tube the delay line is a plurality of gratings 5, Fig. 1, curved out of the plane of their edges and disposed between and secured to side walls 4 and to one another. Preferably at least two of the gratings are oppositely curved so as to be flooded by, yet conform to, a solid cylindrical electron beam. There may be four or six gratings which may be fabricated out of thin molybdenum sheet and clamped or brazed between stainless steel sidewalls. To couple to a waveguide feeder end grating conductors are joined together, bent out and led through the waveguide wall so as to terminate in a probe within a hollow waveguide Fig. 2 (not shown). The grating conductors may be thicker at their ends than at their middle, Fig. 4 (not shown). The delay line may be used in a backward wave oscillator, Fig. 3 (not shown). One grating or set of gratings can give backward wave interaction and a second grating or set of gratings forward wave vibration as in Specification 805,933. The backward wave grating or set of gratings may have reflectionless terminations of lossy coatings. An axial magnetic field focuses the beam. |
