Patent ID: 6617791
Filing Date: 2003-09-09
Classification: H01J

Abstract:
An amplifying apparatus, comprising:an electron gun including a cathode, an anode spaced therefrom, and a grid disposed between said cathode and anode, said cathode providing an electron beam that passes through said grid and said anode, said grid being coupled to an input radio frequency signal that density modulates said electron beam; a drift tube extended from and concentric with said electron gun and anode and surrounding said electron beam, said drift tube including a first portion and a second portion, a gap being defined between said first and second portions; a first polepiece comprising a first centered hole through which said first drift tube portion passes, a first side of said first polepiece facing said cathode, and a second side of said first polepiece facing away from said cathode; a second polepiece comprising a second centered hole through which said second drift tube portion passes, a first side of said second polepiece facing said cathode, and a second side of said second polepiece facing away from said cathode; a first magnetic solenoid located between said first polepiece and said second polepiece and generating magnetic flux, said magnetic flux guiding said electron beam as it passes through said first and second drift tube portions and said gap, a portion of said magnetic flux threading through said cathode; a second magnetic solenoid located on said first side of said first polepiece and producing a magnetic field that effectively cancels said portion of said magnetic flux threading through said cathode; an output cavity connected with said first and second drift tube portions and enclosing said gap, said density modulated beam passing across said gap and coupling an amplified radio frequency signal into said output cavity; and a collector extended from said second drift tube portion and said second polepiece, said electron beam passing into said collector after transit across said gap, said collector having a plurality of electrode stages comprising a first electrode stage and at least one remainder electrode stage, said first electrode stage being connected electrically with said second drift tube portion, said plurality of electrode stages being insulated from each other, said remainder electrode being connected to an electrical potential source having an electrical potential less than that of an electrical potential on said anode, an electrical potential on said first drift tube portion and an electrical potential on said second drift tube portion.