Abstract: The converter is designed to provide very great isolation between its input (AB) and its output (MN) in order to prevent disturbances in the input signal effecting the output signal.At the beginning of each cycle T as defined by a clock circuit (7), a switch (9) allows energy to be transmitted from the input (AB) to the output (MN) for a period of time t1 which is less than T. This period t1 is determined by a comparator (6) which receives a signal representative of the energy received by the input (AB) since the beginning of the cycle from a measuring circuit (1-5).Particularly applicable to protection against interference.

Abstract: The antenna comprises a parabolic reflector (1) and a primary source (2). The reflector (1) comprises a first grating of conductor wires (7) and a second grating of conductor wires (8) which are orthogonal to the wires of the first grating, and with both gratings constituting elliptical reflective surfaces. The sizes of the major and minor axes of the ellipses are determined in such a manner that both operating frequencies of the antenna have identical coverge zones on the surface of the globe.

Abstract: The microwave filter comprises resonators constituted by capacitor-coupled rejector circuits. The tuning and coupling capacitors are composed of parallel metal plates supported and separated by the dielectric of a substrate. The surface of at least one plate of each tuning and/or coupling capacitor is provided with windows which can be sealed-off by a metal deposit in order to permit adjustment of each capacitor to its optimum value.