Velocity modulation tube having floating resonator circuits and short drift spaces

Claim 2

A velocity modulation tube operable in a predetermined operating passband of frequencies comprising at least one first resonator circuit and at least one second resonator circuit each located between an input and an output resonator circuit and a plurality of drift spaces for an electron beam passing through all of said resonator circuits and said drift spaces, said second resonator circuit being placed downstream of said first resonator circuit with respect to said electron beam, each of said resonator circuits comprising interaction gap means operatively associated therewith and contributing to interaction between said electron beam and the electromagnetic field induced in the associated resonator circuit, selected ones of said drift spaces extending between the interaction gap means associated with two adjacent ones of said resonator circuits, said first resonator circuit having a fundamental mode of resonance at a frequency lower than the substantial center frequency of said passband, wherein the improvement is such that the normalized length of the drift space placed immediately downstream of the interaction gap means associated with said first resonator circuit is longer than the normalized lengths of the drift spaces placed immediately downstream of the interaction gap means associated with the other resonator circuits and is not longer than 90* in terms of the reduced plasma angle.

Claim 3

A velocity modulation tube as claimed in claim 1, wherein said second resonator circuit has a fundamental mode of resonance at a frequency higher than said center frequency.

Claim 4

A velocity modulation tube as claimed in claim 2, wherein said first resonator circuit has a fundamental mode of resonance at a frequency lower than the lower edge of said passband.

Claim 5

A velocity modulation tube as claimed in claim 2, wherein said second resonator circuit has a fundamental mode of resonance at a frequency higher than the upper edge of said passband.

Claim 6

A velocity modulation tube operable in a predetermined operating passband of frequencies comprising at least one first resonator circuit and at least one second resonator circuit each located between an input and an output resonator circuit and a plurality of drift spaces for an electron beam passing through all of said resonator circuits and said drift spaces, said second resonator circuit being placed downstream of said first resonator circuit with respect to said electron beam, each of said resonator circuits comprising interaction gap means operatively associated therewith and contributing to interaction between said electron beam and the electromagnetic field induced in the associated resonator circuit, selected ones of said drift spaces extending between the interaction gap means associated with two adjacent ones of said resonator circuits, said first resonator circuit having a fundamental mode of resonance at a frequency lower than the substantial center frequency of said passband, wherein the improvement is such that the normalized length of the drift space placed immediately downstream of the interaction gap means associated with said first resonator circuit is longer than the normalized lengths of the drift spaced placed immediately downstream of the interaction gap means associated with the other resonator circuits and is not longer than 90* in terms of the reduced plasma angle; said second resonator circuit having a fundamental mode of resonance at a frequency higher than said center frequency; the number of said first and second resonator circuits being one each and the normalized lengths of the drift spaces placed immediately downstream of the interaction gap means associated with said input, said first, and said second resonator circuits being 50*, 80* and 35*, respectively, in terms of the reduced plasma angle.

Claim 7

A velocity modulation tube operable in a predetermined operating passband of frequencies comprising at least one first resonator circuit and at least one second resonator circuit each located between an input and an output resonator circuit and a plurality of drift spaces for an electron beam passing through all of said resonator circuits and said drift spaces, said second resonator circuit being placed downstream of said first resonator circuit with respect to said electron beam, each of said resonator circuits comprising interaction gap means operatively associated therewith and contributing to interaction between said electron beam and the electromagnetic field induced in the associated resonator circuit, selected ones of said drift spaces extending between the interaction gap means associated with two adjacent ones of said resonator circuits, said first resonator circuit having a fundamental mode of resonance at a frequency lower than the substantial center frequency of said passband, wherein the improvement is such that the normalized length of the drift space placed immediately downstream of the interaction gap means associated with said first resonator circuit is longer than the normalized lengths of the drift spaced placed immediately downstream of the interaction gap means associated with the other resonator circuits and is not longer than 90* in terms of the reduced plasma angle; said second resonator circuit having a fundamental mode of resonance at a frequency higher than said center frequency; the number of said first and second resonator circuits being one each and the normalized lengths of the drift spaces placed immediately downstream of the interaction gap means associated with said input, said first, and said second resonator circuits being 50*, 80* and 35*, respectively, in terms of the reduced plasma angle.

Claim 8

A velocity modulation tube operable in a predetermined operating passband of frequencies comprising at least one first resonator circuit and at least one second resonator circuit each located between an input and an output resonator circuit and a plurality of drift spaces for an electron beam passing through all of said resonator circuits and said drift spaces, said second resonator circuit being placed downstream of said first resonator circuit with respect to said electron beam, each of said resonator circuits comprising interaction gap means operatively associated therewith and contributing to interaction between said electron beam and the electromagnetic field induced in the associated resonator circuit, selected ones of said drift spaces extending between the interaction gap means associated with two adjacent ones of said resonator circuits, said first resonator circuit having a fundamental mode of resonance at a frequency lower than the substantial center frequency of said passband, wherein the improvement is such that the normalized length of the drift space placed immediately downstream of the interaction gap means associated with said first resonator circuit is longer than the normalized lengths of the drift spaces places immediately downstream of the interaction gap means associated with the other resonator circuits and is not longer than 90* in terms of the reduced plasma angle; said second resonator circuit having a fundamental mode of resonance at a frequency higher than said center frequency; the numbers of said first and second resonator circuits being one and two, respectively, and the normalized lengths of the drift spaces placed immediately downstream of the interaction gap means associated with said input, said first, one of said second, and the other of said second resonator circuits being 50*, 80*, 45* and 330*, respectively, in terms of the reduced plasma angle.

Claim 9

A velocity modulation tube operable in a predetermined operating passband of frequencies comprising at least one first resonator circuit and at least one second resonator circuit each located between an input and an output resonator circuit and a plurality of drift spaces for an electron beam passing through all of said resonator circuits and said drift spaces, said second resonator circuit being placed downstream of said first resonator circuit with respect to said electron beam, each of said resonator circuits comprising interaction gap means operatively associated therewith and contributing to interaction between said electron beam and the electromagnetic field induced in the associated resonator circuit, selected ones of said drift spaces extending between the interaction gap means associated with two adjacent ones of said resonator circuits, said first resonator circuit having a fundamental mode of resonance at a frequency lower than the substantial center frequency of said passband, wherein the improvement is such that the normalized length of the drift space placed immediately downstream of the interaction gap means associated with said first resonator circuit is longer than the normalized lengths of the drift spaces places immediately downstream of the interaction gap means associated with the other resonator circuits and is not longer than 90* in terms of the reduced plasma angle; said second resonator circuit having a fundamental mode of resonance at a frequency higher than said center frequency; the numbers of said first and second resonator circuits being one and two, respectively, and the normalized lengths of the drift spaces placed immediately downstream of the interaction gap means associated with said input, said first, one of said second, and the other of said second resonator circuits being 50*, 80*, 45* and 330*, respectively, in terms of the reduced plasma angle.