Abstract: A folded back doublet antenna including two symmetrical half-plates separd at their one ends by a cut, a long, continuous plate separated from one side of each of the half-plates by a gap, linking sections joining the other external ends of the half-plates to respective ends of the continuous plate, and a line feeding the antenna in the vicinity of the cut and extending along the axis of symmetry of the half-plates. The half-plates have a common width, which is much larger than the width of the continuous plate. The half-plates constitute an input side and the continuous plate constitutes a folded back side.

Abstract: An isobaric device housing rotating electrical contacts, including a wateight housing filled with an electrically insulating liquid at a pressure which is substantially the same as the pressure of the environment in which the device is to be used, and one or more rotating electrical contacts formed by concentric conductive collars located between pairs of insulating rings, which rings are separated and sealed by sealing joints of elastomeric material, the space defined between said rings, collars and sealing joints being filled with an electrically conductive liquid, and washers on each outer end of the contact structure limiting axial movement of the sealing joints which joints also transmit pressure. A plurality of such contact structures may be stacked together on a common shaft thereby forming a multi-contact device. A process for manufacturing such contacts is also disclosed.

Abstract: A system for measuring variations in floatability or floatation force of a loat under varying pressure conditions, including a liquid filled enclosure and means for varying the pressure therein, a dynamometric ring suspended in the enclosure with strain gauges located on each side of the ring, and means for suspending a test float and a ballast from the ring. The system may also include means for preventing inelastic deformation of the ring, and the strain gauges may be connected as adjacent arms of an electrical resistance bridge.