Abstract: The device of the invention comprises, in the terminal (7) of each subscriber, a carrier wave generator which sends this wave to a distribution center (1) as long as the television of this terminal is operating, the absence of this wave being detected in the center by a circuit (4) which then sends a shadow channel to the subscriber. The deflecting of the subscriber's television to a source independent of the center can be done only after the sending of a shadow channel to this subscriber.

Abstract: The device comprises a generator for the analog test signals intended for the equipment to be tested, incorporating a digital computer, a device for the acquisition of the signal supplied by the tested electronic equipment in response to the test signals received by it, as well as display means controlled by the computer for displaying the signals transmitted by the test signal generator and/or the signals received by the acquisition device.

Abstract: The correction control device for a television camera connected to camera channel equipment comprises a mass memory unit containing the camera correction data, a correction memory, a digital computer for transferring the correction data contained in the mass memory unit into the correction memory, as well as correction circuits which are responsive to the correction data contained in the correction memory in order to produce action on the adjustment circuits of the camera and/or of the channel equipment unit.

Abstract: A generating device comprising means for storing test signals in the form of digital samples coupled to a digital-to-analog converter for converting the samples to analog signals at the output of the device. A read/write memory is interposed between the digital-to-analog converter and the storage means. A computer is coupled to the storage means and to the read/write memory. The computer comprises means for generating test signals in the form of digital samples, means whereby the samples stored within the storage means and the test signals produced by the generating means are transferred into the read/write memory as well as means for synchronizing the transfer of samples stored within the read/write memory to the digital-to-analog converter.

Abstract: A television base signal and test signal generator comprises a first memory for storing n eight-bit words (n being a positive whole number) located by a pair of indices (i, j) and a second memory for storing t four-bit words (t being a positive whole number) located by an index k. A first counter and a second counter supply respectively the index i associated with the word to be read in the first memory and the index k associated with the word to be read in the second memory. The index j associated with the word to be read in the first memory corresponds to the value of the four-bit word supplied by the second memory. The two memories are programmed so that at all times the eight bits of the word read in the first memory define entirely the desired base signals and test signals.

Abstract: A processing arrangement making it possible on the one hand to measure the amplitude of the horizontal sync. pulses and correct them, in order to give them a predetermined amplitude, and on the other hand to measure the amplitude of a signal at the frequency of the chrominance sub-carrier, and to correct it in order to give it a predetermined amplitude, the two amplitudes references thus introduced into the video signal forming, at the time of reception (or read-out) of the signal, absolute references which are used to automatically correct distortions produced in the signal.

Abstract: In a processing circuit of the type using pre-emphasis of the composite color television signal and frequency modulation, an amplitude compressor is used for selectively compressing the higher portion including the chrominance sub-carrier, of the frequency spectrum of the composite signal, prior to pre-emphasis of the latter.