Abstract: In a multistage collector used in a linear beam tube such as an IOT or klystron, electrode stages are separated by ceramic rings having metallised surfaces to provide distributed bypass capacitors. This eliminates or reduces leakage or any radio frequency energy from the interior of the collector to the outside.

Abstract: An electron gun arrangement includes a cathode having a front surface and control grid located in front of it. The control grid is mounted via a cylindrical support on a Kovar mount. The cathode is supported by a cylindrical support mounted on a Kovar support. Ceramic material being located between the two supports. The vacuum envelope within which the electron gun is contained includes the Kovar support and a flexible member with which it makes a vacuum seal, this member being of copper. The copper member is sealed to a ceramic cylinder via metal flanges. The assembly permits the spacing between the cathode and grid to be maintained while the copper member permits thermal expansion to occur to maintain vacuum integrity.

Abstract: In a multistage collector used in a linear beam tube such as an IOT or klystron, electrode stages (1, 2 and 3) are separated by ceramic rings (5 and 6) having metallised surfaces (7 and 9) to provide distributed bypass capacitors. This eliminates or reduces leakage or any rf energy from the interior of the collector to the outside.

Abstract: In an electron beam tube arrangement, such as an IOT amplifier, an input cavity surrounds an electron gun. The cavity includes parts which are at high and low relative electrical potentials. These are separated by RF chokes to provide de isolation whilst acting as a short circuit to high frequency radiation coupled into the cavity. The arrangement also includes a bypass capacitor located behind the electron gun which short circuits stray or leakage radiation to prevent deterioration of the amplified signal. The bypass capacitor presents a distributed capacitance of low inductance. In one embodiment, the RF choke and bypass capacitor include insulating material defined by a common member on which metallisation layers are deposited.

Abstract: An electron beam tube includes an electron gun included within a vacuum envelope defined partly by a ceramic cylinder. The ceramic cylinder includes straight sided portions and with an intervening conical section between them. The straight sided portions and form part of two r.f. chokes, being metallized on their inner and outer surfaces and forming a connection with a cavity forming part.

Abstract: In an electron beam tube arrangement, such as an IOT amplifier, an input cavity surrounds an electron gun. The cavity includes parts which are at high and low relative electrical potentials. These are separated by RF chokes to provide dc isolation whilst acting as a short circuit to high frequency radiation coupled into the cavity. The arrangement also includes a bypass capacitor located behind the electron gun which short circuits stray or leakage radiation to prevent deterioration of the amplified signal. The bypass capacitor presents a distributed capacitance of low inductance. In one embodiment, the RF choke and bypass capacitor include insulating material defined by a common member on which metallization layers are deposited.

Abstract: In an output resonant cavity used with a linear electron beam tube such as an IOT, magnetic material is mounted on walls of the cavity and defines annular channels within which coils are located to provide focusing of an electron beam travelling along the axis of a tube located in apertures in the cavity walls. An inner rim locates the electron beam tube with respect to the cavity.

Abstract: In an electron beam tube such as a klystron, a vacuum seal comprises a ceramic cylindrical wall on which are brazed metal rings which are welded to flares and fixed to electrodes and of a collector. Ceramic rings and are located between the metal ring and the electrodes. The cylindrical wall includes inner flanges which overlap the inner peripheries of the metal rings hence reducing the likelihood of arcing occurring between them and other parts of the arrangement at different potentials. In other embodiments of the invention, the ceramic rings are extended to shield the inner edges of the metal rings or a separate ceramic tube is positioned within the metal rings to provided shielding.

Abstract: In an electron beam tube, such as an IOT, ferrite loaded silicone rubber or some other ferrite loaded dielectric material, is carried by a wall of an input cavity. The material absorbs r.f. energy, reducing coupling between different parts of the tube which could otherwise result in undesirable oscillation. Furthermore, its provision on part of the input cavity wall enables easy access to be made for replacement and servicing requirements.

Abstract: A linear electron beam tube has voltages provided thereto, an electron gun, and an output resonant cavity operatively arranged together. An internal body portion, an external body portion and an insulating portion are provided. The internal body portion, external body portion, and insulating portion at least partially define an annular input resonant cavity. The internal body portion is provided with a high voltage, with respect to the external body portion, and the internal and external body portions are separated by the insulating portion so that the internal and external body portions have no electrically conductive connection therebetween. The internal body portion is in electrical contact with the electron gun. The annular input resonant cavity at least partially defined by the internal and external body portions surrounds the electron gun.

Abstract: An electron beam tube arrangement has an output cavity resonator circuit which includes a first output cavity, a second output cavity being coupled thereto by means of a coupling loop. The coupling loop is located in the first cavity and connected to said second cavity. In one embodiment of the invention, the second cavity also contains a coupling loop which is electrically connected to that in the first output cavity.