Abstract: This invention relates to a push-button type switch comprising electrical contacts actuated by a head made up of a command button (1) associated with a body (2) within which is housed a piston (4) and a push rod (6) acting on electrical contacts which are able to slide and to pivot within the body (2) along an axis (X—X) without being able to pivot relative to one another, the push rod (6) being fitted with a first catch (7) and a second catch (8) characterized by the fact that the piston (4) is fitted with a command device (41) capable, when the button (1) is pushed, of actuating the first catch (7) called the stop catch immobilizing the push rod (6) in the “stand-by” position and then releasing the push rod (6) which can move into the “held” position where it is immobilized by the second catch (8) which is used to maintain contact.

Abstract: A receiver system processes signals transmitted via a multipath dispersive transmission medium. It includes a device for digitizing the received signals to supply corresponding digital signals. An adaptive digital equalizer responsive to the digital signals supplies information symbols. A symbol-clock signal controls the digitizer and the equalizer. A timing signal recovery device responsive to the digital signals and to the information symbols derives a phase control signal for controlling the phase of the symbol-clock signal.

Abstract: A digital signal receiver comprises receiver and demodulator means producing from the received signal a succession of complex elements. It produces sequences of successive complex elements consisting of conjugate elements of homologous elements used at the transmitting end. The sequences so used at the receiving end are synchronized to the homologous sequences used at the transmitting end. The complex elements obtained at the output of the demodulator are multiplied by a corresponding sequence of successive complex elements so produced and synchronized. The resultant complex elements appearing during the duration of an information symbol are summed over said duration to produce an estimate of the original information symbols used at the transmitting end. The complex elements obtained at the output of the demodulator are analyzed to identify a marking introduced at the transmitting end.