Abstract:
A high frequency velocity modulated beam tube is disclosed having a beam collector structure insulated from the body of the tube. A high frequency conductive housing surrounds the insulator structure to prevent stray radiation from the tube. A wave energy attenuator is disposed in the housing to minimize excitation of high Q resonant modes in the housing. The attenuator comprises plural turns of a dielectric conduit having a cooling liquid flowing therethrough. In a preferred embodiment the conduit forms the attenuator which is cooled by the liquid. In another embodiment the coolant is lossy to form the attenuator.
Abstract:
A tunable high frequency velocity modulation beam tube has a plurality of floating resonators arranged along a beam path intermediate an input circuit and an output circuit for velocity modulating the beam to provide bunching of the beam at the output circuit. The cavity resonators are tunable over a relatively wide band for tuning the electronic bandwidth of the tube over a relative wide tunable band. A plurality of floating resonators are each loaded by a series resonant loading circuit with the Q''s and frequencies adjusted to provide a certain flat electronic bandwidth. The loading circuits are tuned and loaded such that the loss introduced into the floating resonators is frequency dependent over the tunable band of the tube in order to maintain the given electronic bandwidth over the tunable band of the tube.
Abstract:
The collector incorporates an impact surface portion at the downstream end for collecting substantially all the electrons in the electron beam. The impact surface portion closely approximates the locus of points equidistant from the constricted mouth portion of the collector. By this means amplitude modulation of the few secondary high-velocity reflected electrons returning from the collector and refocused back through the beam tunnel is reduced.