Abstract: A controller, which is normally used for controlling different modes is used for circuit protection. The suipply voltage and control signals from the switched mode power supply to the controller are modified when a short circuit occurs. In response thereto, the controller switches "off" a mode-control signal and the switched mode power supply operates in standby mode.

Abstract: The present invention relates to a method of processing a digital signal of dimension k, in a so-called secure communication system, such that the digital signal (y) at output cannot be deduced from the digital signal (x) at input, consisting in dispatching the digital signal (x) to a device effecting a one-way function.The method includes the following steps:the digital signal (x) at the input is dispatched to a circuit C (1, 2) which gives as output a digital signal (x") of dimension n acceptable to the one-way function;the signal (x") from the circuit C (1, 2) is dispatched to the circuit effecting the one-way function giving as output the digital signal (y).The invention applies in particular to so-called secure communication systems.

Abstract: A microwave polarizer particularly in a system for coupling energy between a waveguide and a transmission line. The polarizer reduces cross polarization by means of the probes being adjusted to an input impedance of less than 50 ohms, in particular to 20 ohms, by reducing the penetration depth of the probes. The smaller penetration depth also increases the distance between the two probes, which reduces cross polarization.

Abstract: A toothed lever 11, 12 which engages in a toothed rim 21 of an intermediate wheel 5 when the tape drive changes over from the winding mode to the stop state, a pivot 18 for the intermediate wheel 5 is formed at the point of engagement, over which pivot the toothed rim 21 of the intermediate wheel 5 rolls and passes from the previously engaged supply spool 1 or take-up spool 2 into a disengaged position. It is then necessary only for the spools 1, 2 themselves to be braked.

Abstract: Low-redundancy codes are increasingly being striven for, such codes thus inevitably requiring comparatively long code words. However, since the memory requirement for coding tables increases considerably with the length of the code words, the use of code tables is then no longer expedient. Instead, coding is then effected by selecting the optimum code word in each case from a plurality of different code words taking account of coding; prescriptions and spectral decisions. For this purpose, the maximum run length for each code word is also determined, inter alia, but the spectral decisions are decisive as long as the maximum run length does not exceed a predetermined maximum value. Provided that the end of one code word and the beginning of a succeeding code word have the same binary value, incorrect decisions in the selection of the optimum code word may arise in the region where the synchronizing pattern is keyed in.

Abstract: A high-voltage transformer for a television display device having a core made of two core parts. One end of a core limb is chamfered or rounded on the outside such that the contact region is distal from the outer edge of the core limb. The end of the core limb is preferably provided with a bevel.

Abstract: The disclosure relates to a flexible-core electrical cable whose end is stripped and carries a metal disk of diameter not exceeding that of the cable sheathing and having a central hole. The disk is fitted against the end of the sheathing with the core passing through the central hole. Conducting solder is applied to rigidify the flexible core and attach it mechanically to the disk. The invention is applicable to flexible-core high-voltage cables, in particular those used on high-voltage transformers fitted with conducting connection pellets.

Abstract: A transformer to achieve a precise amplitude for the operating voltages produced by the auxiliary windings, and such that the construction and production of the transformer are simplified. An auxiliary winding is split into a plurality of winding elements disposed in different chambers of a chamber-type coil former. One of the chambers is disposed in the region of the air gap of a U/I core or of a U/U core, the two U-core halves having parallel limbs of different lengths.

Abstract: A method of digitization of an intermediate frequency signal having a bandwidth that can change from one standard to another and of which one of the frequency limits of this band is substantially constant, wherein before converting the analog signal into a digital signal, the signals of the channels (S.sub.if.sup.N+1, S.sub.if.sup.N-1) adjacent to the frequency band of the signal to be digitized are eliminated in three stages: in a first stage, the signals (S.sub.if.sup.N+1) of channels adjacent to said substantially constant frequency limit are eliminated by filtering; in a second stage, the signal to be processed is transposed in frequency so that in the transposed signal the variable frequency limit of said band of the signal to be digitized has a substantially constant value; in a third stage, the signals of channels adjacent to the transposed signal are eliminated by filtering. The invention is applicable to the processing of digital IF video signals.

Abstract: In an electronically commutated head drum motor in combination with a motor control circuit, commutation control and tacho signals are generated from the commutation of winding strands. One of the winding strands is used for the phase detection of the read/write heads arranged on the perimeter of the rotating head drum. A commutation signal is derived from the commutation of this winding strand and the commutation signal is set in relation to the reference signal of a signal track to be recorded or scanned.

Abstract: The disclosure concerns a device for estimation of movement by block matching in an image compression system based on blocks, characterized in that it comprises N lines.times.M columns of means of calculation of an error function between two values, N.times.M means of memorization of values representing the block whose movement is to be estimated, N.times.M means of memorization of values representing a block of a reference window, the two means of memorization being linked respectively to the means of calculation, M means of adding that totalize simultaneously the values of the error function for a column of N elements of calculation. The invention is applicable to image compression.

Abstract: The invention relates to a device for interfacing between at least two communications buses. The device includes a two-way interface for each of the communications buses, a circuit for comparison of messages received by the interfaces, and a circuit for resolving conflicts of priority between messages overlapping in time so that the conflict resolution circuit authorizes the transmission of the higher priority message through the interface or interfaces to the communications buses from which the higher priority message did not originate.

Abstract: The disclosure concerns a dual-mode ISDN/STN visiophone terminal, including at least one audio equipment and one video equipment respectively connected to an ISDN via a dual-mode ISDN/STN audio coder/decoder incorporating an ISDN audio coder, an ISDN audio decoder, an STN audio coder and an STN audio decoder, and via a dual-mode ISDN/STN video coder/decoder incorporating an ISDN video coder, an ISDN video decoder, an STN video coder, and an STN video decoder, wherein in order to provide an answering/recording function in said visiophone terminal a RAM memory is used to store audiovisual messages in STN mode, and wherein the outputs of the ISDN audio and video decoders are connected respectively to the inputs of the STN audio and video coders in order to record in the RAM an audiovisual message sent by a calling party via a remote terminal, and wherein the outputs of the STN audio and video decoders are connected respectively to the inputs of the ISDN audio and video coders in order to send an audiovisual mess

Abstract: A polarizing splitter device includes a double prism having an entry face for receiving a beam of unpolarized light, a polarizing splitter transmitting the polarized light in a first polarization direction, and reflecting the light polarized in a second polarization direction. The double prism also has a reflection face provided with a mirror receiving the light reflected by the polarizing splitter as well as an exit face for receiving and transmitting the light transmitted by the polarizing splitter and reflected by the mirror.

Abstract: This invention concerns a television receiver equipped with speakers fitted in a particular manner. The television receiver includes at least one speaker located at the bottom of a cavity in the outer surface of the case of said television receiver, this cavity being located in at least one of the faces of said case, said bottom and said speaker being oriented so that the sound from said speaker radiates at least partially towards the front of said television receiver, and said bottom of said cavity being close to the rear face of said case.

Abstract: A radio-frequency (RF) receiver generally contains an RF amplifier, a mixer stage, a mixer oscillator, a demodulator and an AGC (automatic gain control) circuit, to which the output voltage of the demodulator and a set voltage value for the automatic gain control are applied. Such RF receivers have a non-optimal signal-to-noise ratio under certain circumstances. The present invention improves the signal-to-noise ratio in such high frequency receivers, as well as the effectiveness of the AFT (automatic fine tuning) circuit. The amplitude of the AGC set voltage value is regulated depending on the frequency of the received RF signal so that the mixer stage is optimally controlled at all frequencies of the RF signal. In one embodiment, a PLL circuit connected to the output of the intermediate frequency amplifier to regenerate the non-modulated image carrier, is further used to ensure automatic fine tuning by regulating the frequency of the mixer oscillator.

Abstract: A rack drive contains a suspension tooth element which is formed by a rack which has a guide opening parallel to its row of teeth. The rack opening is guided on a bearing bolt of the drive pinion for the rack. The suspension tooth element is preferably connected via a drive pin to a device which can be variably positioned and is produced integrally from an acetyl polymer. The rack drive can advantageously be used as a positioning device for controlling a scanning and/or recording device in a recording and/or playback unit for optical recording media but is not limited to such.

Abstract: A drum assembly for a magnetic tape reading and writing system, comprises: a static drum; a rotary spindle coaxial with the static drum and connected to a drive motor; a rotary drum mounted on the spindle; at least one pair of read heads for video and a pair of read heads for audio, each of the read heads rigidly attached to the rotary drum; a first rotary transformer mounted inside the rotary drum, on the rotary spindle, and connected to one of the pairs of read heads; and, a second rotary transformer mounted outside the rotary drum, on the rotary spindle, and connected to the other one of the pairs of read heads.

Abstract: Due to low output voltage during flyback mode of start phase the secondary current cannot be fully discharged in time. The current buildup will eventually damage the output transistor if the current is not limited.In order to prevent the current build up during start phase, the storage time of the output transistor of the SMPS has to be reduced.During the startup phase a negative bias capacitor is not fully charged. Thereby the base of an output transistor is not biased sufficiently when the transistor is switched off. So the transistor could not operate safely if the collector voltage is higher than Vceo.It is the object to keep charges, which are stored on the capacitor during startup phase and to reduce discharging of the capacitor.According to this invention means are provided between the base and the emitter of the output transistor. It is preferred that said means are realised by a resistor and a diode, connected in series.

Abstract: Electrical contact surfaces, especially when connected to a chip, are designed to be purely functional. However, according to the present disclosure, the contact surfaces are designed so that their external shape is that of a visible letter or symbol with a meaningful content. These contact surfaces may, e.g., be placed on cassette casings for recognition. In a stripe or bar code unit consisting of several code components, i.e., bars, individual bars are electrically conductive to facilitate additional coding. The electrically conductive bars or the contact surfaces are preferably connected to the terminals of an integrated circuit.