Linear beam tube modulation system using modulation of first grid

Claim 1

A system for operating a linear beam tube comprising: a linear beam tube which includes in turn: an electron gun for emitting electron beams, the electron gun having a first grid electrode; a microwave amplifying portion provided with at least an input section receiving the electron beams and a microwave signal, and a microwave signal output section coupled to an output utilization device and amplifying microwaves; and a collector for collecting the electron beams passing out of the microwave amplifying portion; first means for conducting microwaves modulated by modulating signals of a first amplitude level to the input section of the microwave amplifying portion of the linear beam tube, said first means including a video signal generator; a level distributor for distributing video signals into video signals having a higher amplitude level than said first amplitude level and into those signals having a second lower amplitude level; a video signal amplifier for amplifying the video signals having said higher amplitude level and supplying said amplified higher level video signals to the grid electrode of the electron gun; a video carrier signal oscillator for generating video carrier signals; a video carrier amplifier and modulator for modulating said video carrier signals by those of the video signals from the level distributor which have said second lower amplitude level; and a circulator for supplying said input section of the microwave tube with said video carrier signals modulated by said video signals having said second lower amplitude level; and second means responsive to said modulating signals and connected to said first grid electrode of the electron gun for density modulating the electron beams by said modulating signals in said first grid electrode of the electron gun said second means modulating said electron beam by a higher amplitude level than said first amplitude level.

Claim 2

A system for operating a linear beam tube comprising: a linear beam tube which includes in turn: an electron gun for emitting electron beams, the electron gun having a first grid electrode; a microwave amplifying portion provided with at least an input section receiving the electron beams and a microwave signal, and a microwave signal output section coupled to an output utilization device and amplifying microwaves; and a collector for collecting the electron beams passing out of the microwave amplifying portion; first means for conducting microwaves modulated by modulating signals of a first amplitude level to the input section of the microwave amplifying portion of the linear beam tube, said first means including a video signal generator; a level distributor for distributing video signals into video signals having a higher amplitude level than said first amplitude level and into those signals having a second lower amplitude level; a video signal amplifier for amplifying the video signals having said higher amplitude level and supplying said amplified higher level video signals to the grid electrode of the electron gun; a video carrier signal oscillator for generating video carrier signals; a video carrier amplifier and modulator for modulating said video carrier signals by those of the video signals from the level distributor which have said second lower amplitude level; and a circulator for supplying said input section of the microwave tube with said video carrier signals modulated by said video signals having said second lower amplitude level; and second means responsive to said modulating signals and connected to said first grid electrode of the electron gun for density modulating the electron beams by said modulating signals in said first grid electrode of the electron gun said second means modulating said electron beam by a higher amplitude level than said first amplitude level.