Abstract: Device for estimating, at high temperature, the electromagnetic properties of a material, including:an oven (1, 19, 20);a waveguide (3) disposed at least in part in said oven, a housing for a specimen piece of uniform thickness made of said material, this specimen piece being such that, when it is disposed in said housing, its outer periphery matches the inner surface of the waveguide;means (4, 5, 6) for applying an incident very high frequency electromagnetic wave to the waveguide (3); andmeans (4, 5, 6) for collecting the electromagnetic wave reflected by said specimen piece.A vertically disposed waveguide has (3) said housing provided at the open lower end (3B ).

Abstract: A process and apparatus are provided for checking the electric continuity of an electrically conducting material device, in which a current is injected between two points of said device and the resulting voltage between these points is measured. The invention is remarkable in that said current is an AC current and its pulsation is chosen sufficiently large so that the impedance between the two points, measured by the ratio of said voltage and of the current, may be considered as being equal to the product of the inductance of the path of the current between said points multiplied by said pulsation.

Abstract: A device is provided for estimating the electromagnetic characteristics of a dielectric or magnetic material by means of a hyperfrequency electromagnetic wave which device comprises a coaxial line formed of a tubular body (2,3) and a core (1), which are rigid and coaxial with, at one end, a housing such that the external and internal peripheries of an annular sample piece (17) are respectively in tight friction contact with the inner surface of said tubular body and with the external surface of said core, said tubular body being formed of two parts which can be assembled together.

Abstract: A device is provided for connecting together two coaxial ultra-high frequency structures of different diameters. This device is remarkable in that it has itself a rigid coaxial structure comprising a central core in the form of a truncated cone, as well as a peripheral sheath whose internal wall is a truncated cone shaped surface, the small bases of the truncated cones of said central core and of said peripheral sheath of said connection are two parallels of the same sphere centered on the apex of the truncated cone shaped surface of said internal wall and the large bases of the truncated cones of said central core and said peripheral sheath of said connection are two parallels of a second sphere concentric to the first one.

Abstract: This invention relates to a system for establishing at ultrahigh frequency the electrical continuity between two conductive elements, wherein:the annular joint is made of a resilient metal and is in the form of a washer;the junction face of one of said conductive elements comprises an annular projection directed towards the other conductive element and surrounding a recess;the junction face of the other of said conductive elements comprises at least one bearing portion disposed opposite said annular projection, so that the peripheral part of said washer can be pressed between said annular projection and said bearing portion, due to the action of said tightening means; andblocking means are provided to maintain the central part of said washer inside said recess, so that, when said conductive elements are pressed against each other, said washer deforms elastically in non-irreversible manner, to take the shape of a flare widening in the direction of said other element.