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.