Thomson-Csf

Thomson Tubes Electroniques

Guy Clerc

Pierre Gerlach

Arvind Shroff

Roger Hoet

Michel Langlois

Jean De Cachard

A grid for an electron tube with an axial beam which includes an apertured part through which the electrons of the beam are intended to pass. The grid is in the form of a bell and is made of a single material. The apertured part is located at the top of the bell but is placed in the bottom of a hollow so that the electrons passing through the grid around its periphery are focused onto the axis. Such a grid may find particular application to IOT-type tubes.

Electron tube with axial beam and pyrolitic graphite grid

The disclosure relates to a radiofrequency generator including an Inductive Output Tube with an electron gun followed by an anode, the gun being raised to a high voltage in use, means producing an input radiofrequency signal and means of transmitting it to said IOT such that it provides an output signal whose power is amplified compared to said input signal, wherein said means producing said input radiofrequency signal, said means transmitting it to said IOT and said gun are confined in an electrostatically screened enclosure that is electrically isolated from the potential of the anode and can be raised to a high voltage, said gun receiving its high voltage from said screened enclosure. The invention is applicable to very high power radiofrequency generators.

Very high power radiofrequency generator

Electron gun having a grid

Disclosed is a thermionic cathode for electron tubes comprising a material that has a substrate, a compound of an element forming an emitting monolayer, chosen from among the rare earth zirconates, rare earth hafnates, rare earth aluminates and rare earth berylates, and a reducing agent which, at the working temperature of the cathode, reacts with the compound releasing the element that forms the monolayer. Application in particular to electron grid tubes. FIG. 1.

Thermionic cathode for electron tubes and method for the manufacture

An electron tube includes cylindrical electrodes which are mounted coaxially. The electrodes include a cathode surrounded by a grid, with the cathode and the grid defining an input resonant cavity having an active zone. The cavity extends on both sides of the active zone. The central part of the active zone is located at a point where the voltage reaches a maximum. The resonant input cavity is folded back on itself so that both ends of the cavity are at the base of the tube.

Grid electron tube with a folded cavity structure

The invention provides a direct heating thermo-electronic emission cathode comprising a pyrolytic graphite support and an emissive coating formed of a mixture of tungsten and lanthanum oxide, the tungsten being transformed in its surface part into tungsten hermicarbide.

Direct heating cathode and a process for manufacturing same

A directly-heated cathode for power electron tubes such as triodes, tetrodes or pentodes comprises a cylindrical sleeve constituted by a lattice of crossed wires forming the emissive portion of the cathode and by two conductive plates attached respectively to each end of the sleeve. In order to permit free deformation of the cathode, a flexible metallic bellows element is fixed between one of the plates and the corresponding end of the cylindrical sleeve.

Directly-heated cathodes

A direct heating thermionic emission cathode for high frequency tubes of the diode, tetrode or pentode type. It comprises a pyrolytic graphite support and a lanthanum hexaboride-based thermoemissive material, these elements being separated by a layer which constitutes a diffusion barrier and comprises a tantalum or hafnium carbide, a metal of the platinum group or a boron compound.

Growing community of inventors

Thonon-les-Bains, France

Guy Clerc