H01J25/00—Transit-time tubes, e.g. klystrons, travelling-wave tubes, magnetrons
H01J25/34—Travelling-wave tubes; Tubes in which a travelling wave is simulated at spaced gaps
H01J25/42—Tubes in which an electron stream interacts with a wave travelling along a delay line or equivalent sequence of impedance elements, and with a magnet system producing an H-field crossing the E-field
H01J25/44—Tubes in which an electron stream interacts with a wave travelling along a delay line or equivalent sequence of impedance elements, and with a magnet system producing an H-field crossing the E-field the forward travelling wave being utilised