Abstract: The invention relates to a scratch pad memory system having a table of contents for identifying program material recorded on a magnetic tape in a cassette or cartridge with program material being recorded or changed responsive to user command. The scratch pad memory system comprising an address register, a read only storage, and having an interface for read/write storage and a text displaying terminal coupled to a television receiver for display of program material.

Abstract: To obtain a duo-binary FSK modulation, the modulating binary signal train has a three state partial response and is fed through a precoding, a transition-type coding, a simplified MSK modulation at the carrier frequency, a frequency division by two, and a multiplication by the same signal delayed by one binary element period. In order to obtain a "tamed FSK" modulation, the modulating binary signal train has a five state partial response and is fed through precoding, a transition-type coding, a simplified MSK modulation at the carrier frequency, a frequency division by two, a multiplication by the same signal delayed, for one part, by one binary element period and, for the other part, by two binary element periods. A TFM modulation is obtained by using the FSK duo-binary generating process, but a wave shaping filter is connected between the division by two circuit and the multiplication circuit.

Abstract: The invention relates to doublet plates and the method of making them so t they may operate at very high frequencies.

Abstract: A system broadcasts videotext data in the form of data packets originating from numerical data coming from several paths. Each packet has a prefix which contains synchronization and path identification code signals, a format signal which indicates the length of the data which follow the prefix. The transmitting station has as many coupling devices as there are paths for originating data. The coupling device has a data memory coupled to drive to a multiplexing circuit under the control of a common governing circuit. An inhibition order is given either as soon as the memory is full, or as soon as a counter has reached a pre-determined count. Then, the memory is connected to the multiplexing circuit, into which the stored data is emptied. The system is characterized in that a small capacity buffer is used between the memory and the input circuit for reading data out of the buffer memory responsive to a programmer. A transcoder treats the broadcast data to fit it into the system format.

Abstract: A coding process for the adaptive prediction differential PCM type. An error signal e.sub.t is formed between a sample of signal y.sub.t to be coded and a prediction signal p.sub.t of said signal. The prediction signal p.sub.t is formed from restored signals y.sub.t and e.sub.t by two linear filtering operations, the first relating to N successive samples of y.sub.t and using coefficients A1.sub.t, A2.sub.t, . . . , AN.sub.t and the second relating to P successive samples of e.sub.t and using coefficients B1.sub.t, B2.sub.t, . . . , BP.sub.t, the coefficients A1.sub.t, A2.sub.t, . . . , AN.sub.t and B1.sub.t, B2.sub.t, . . . , BP.sub.t being sequentially adjusted at each time t so that the mean power of error signal e.sub.t is minimal. Instead of carrying out the prediction on the basis of signals y.sub.t and e.sub.t only according to the invention, use is also made of the real signal y.sub.t and the real error e.sub.t. A linear filtering of y.sub.t using the coefficients A1.sub.t, A2.sub.t, . . . , AN.sub.

Abstract: Television system using a marking code superimposed on a picture.According to the invention, this code is constituted by a strip located in the right-hand part of the picture and formed by a periodic sequence of white and black areas constituting a clock and by a strip located in the left-hand part of the picture and formed by a sequence of white or black areas constituting the actual code. A decoder detects the presence of clock signals and compares the code received with stored codes.

Abstract: A device for following and recursively estimating the local state of pict contours defined by lines of N points distributed in accordance with an orthogonal sampling structure, said points being defined by successive numerical samples.The invention also relates to a differential coded pulse modulation coder and a differential coded pulse modulation decoder.

Abstract: A subscription card for videotex receivers, comprising:(a) a support,(b) means for processing the information, comprising in particular a control unit governing an arithmetical and logical unit and a live memory,(c) an interface permitting exchanges between the card and the apparatus in which it is inserted (charging station or receiver), further comprising:(d) a programmable memory comprising a plurality of locations for receiving numerical subscription blocks C.sub.i,(e) a dead memory containing instructions for proceeding with the recording and selection of said subscription blocks, and for carrying out a calculation,(f) a calculation circuit receiving, from the receiver in which the card is inserted, numerical messages M.sub.i and receiving from said programmable memory a numerical subscription block C.sub.i, this circuit being adapted to work out an algorithm whose parameters are provided by the subscribers' keys C.sub.

Abstract: The present invention relates to a process for making semi-conductor components on an amorphous substrate, comprising two phases, wherein, in a first phase, the substrate is introduced into a deposition chamber and a uniform deposit is made of four successive primary layers on all this substrate, without contact with the outside atmosphere: a first layer of protective insulating material, a second layer of semiconductor material, a third layer of insulating material, of smaller thickness than the first layer, and finally a fourth layer of a metal; and, in a second phase, the substrate coated with these four layers is withdrawn from the deposition chamber and the last three layers are subjected to photoetching and ancillary deposition operations, which are appropriate for the structure of the component to be obtained.

Abstract: A text video-transmission system comprising an information emitting center and receiving stations, the emitting center comprising encryption means using an operating key, each receiving station comprising decryption means using the operating key, wherein in this system, the encryption means of the emitting center comprise: a generator delivering a numerical signal representing an operating key K, this key changing randomly at predetermined intervals; an automatic encryption means comprising: a discriminator with an input connected to a magazine memorizing circuit from which it receives clear octets, this discriminator being capable of distinguishing, among these clear octets, those wherein the 7th and 6th binary elements are zero, an OR-exclusive logic circuit connected to the discriminator from which it receives octets wherein the 6th and/or 7th binary elements are not zero, this logic circuit having an output which carries encrypted octets; a generator of encoding octets, the decoding means of each receivin

Abstract: A system for transmitting information between an emitting center and receiving stations, comprising: a subscription administration center generating a plurality of subscriber's keys C.sub.i changing randomly at relatively long intervals of the order of a month; in the emitting center: a generator of an operating key K changing randomly at relatively short intervals of the order of a few minutes; a circuit for forming messages M.sub.i obtained from said subscriber's keys C.sub.i and from the operating key K by means of an algorithm, all the messages M.sub.i then being directed towards the emitting center; and automatic encryption means using the operating key K, in each receiving station: a subscription holder on which is recorded a signal corresponding to at least one of the subscriber's keys C.sub.i ; a circuit for restoring the operating key receiving the messages M.sub.i and the subscriber's key C.sub.

Abstract: In a system for broadcasting data in combination with a television signal, he emitting station broadcasts, sets (blocks) of data which may be in-coming from several paths, the sets of data being time multiplexed. The present invention makes it possible to use the same television broadcast system, regardless of the television standards which may be used, with a minimum of modifications in the conventional television receivers. The frequence of the binary elements used to transmit data is made to vary as a function of the band width of the television signal which in turn, corresponds to the TV broadcast used in the area where the data is broadcast.

Abstract: An arrangement for the electrical control of the keyboard of a video or audio tape recorder includes electromechanical levers acting on the usual rod system associated with the keyboard in substitution of the conventional keys. The levers are essentially bellcranks and are associated with tumblers and electromagnets.

Abstract: There is provided a one-way data transmission system wherein a transmitter station transmits in the form of data packs data from a plurality of channels, the said packs being time multiplexed.One channel amongst the plurality of channels is allotted to transmitting date information. In the receiver equipments, the dead memory stores not only the channel code, but also a subscription period information which permits to validate the channel code depending on the date information received from the date channel. Automatic dead-memory distributors are provided which receive data from a control channel transmitted by the system, like other channels. The system is compatible with television systems.