Thomson-csf

Thomson-brandt

Michel Van Den Driessche

Gerard Coussot

Olivier Menager

Jean C Coschieri

Jean C Guillon

Bernard Duret

This invention concerns television scanning circuits. It involves a scanning startup circuit comprising a capacitor, and means of gradual charging or discharging, to produce a priority voltage transmitted at startup to replace a control voltage, regulating a chopped power supply circuit which is to be started up progressively. At the end of a certain period of time, the regulation control voltage takes over from the original voltage which, at startup, is at a level such that it prevents over-consumption of current in power components. The circuit is also protected against voltage surges, being halted and restarted automatically and gradually in the event of such a surge.

Scanning control circuit for a television receiver, with gradual startup

Integrated interface circuit between a television receiver and its

Devices for displaying a label on a visualization screen. The information display inserted into a background image is provided by a character-generating circuit. The stability of the label requires synchronization of the vertical scanning of the image and of the label. This synchronization is obtained by measuring the current which flows through the deflector of the cathoscope tube: the information acquired, amplified, is applied to a threshold detector which controls the display circuit. The beginning and the end of synchronization are regulated by two reference voltages. The invention applies to the display of information on television receiver or visualization console screens.

Synchronization device for a character-generating circuit and a vertical

The invention relates to a circuit for decoding chrominance signals from the composite videofrequency signal in the Secam color television system. In order to direct each chrominance signal to the corresponding channel, it is proposed in accordance with the invention to extract the demodulated signals at the beginning of each line and to treat them in the first place by a controlled circuit which equalizes their d.c. voltages, in the second place by a color identification circuit which synchronizes the commutator with the television transmitter and in the third place by a 'keeper' circuit for identifying the Secam process which inhibits the chrominance circuit if the transmission is by another process or parasitized. Application to television receivers using the Secam system.

Circuit for decoding chrominance signals in the Secam television system

An elastic surface wave filter including on the surface of a plate, an emitting transducer, a surface wave coupler, and means for receiving the waves radiated by the coupler. The means for receiving includes two transducers each having two terminals with one terminal of each being in common with one terminal of the other. The common terminal serves as a phase reference and the voltages induced at the remaining terminals are in phase opposition to one another in the transmission band of the filter.

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Paris, France

Michel Van Den Driessche