Abstract: In a plasma display screen them is a circuit which alternately applies a positive and negative voltage to the general capacitance of the screen or panel for a reset process. In the current path there is an inductance to ensure the recovery of the energy to the total capacity. The aim is to improve the drive and the erase process of a pixel in such a circuit The capacity (Cp) is cyclically connected via a third switch (T3) to such a third operating voltage that the voltage (UCp) at the capacitance (Cp) has a period of zero voltage between those of positive and negative voltage. Especially for a control circuit for a plasma display screen for a television receiver.

Abstract: A system for rapidly rewinding a tape from a first spool onto a second spool of a recording device. First and second sensors respectively sense the rotational speed of the first and second spools. The thickness of the tape, the radius of a core of the spool and the total thickness of tape present on the core are stored. A calculator receives the rotational speeds, the tape thickness, the radius and the total thickness, and calculates the remaining rewinding time and provides a deceleration signal while the remaining rewinding time is sufficient to decelerate the first spool to a final rotational speed.

Abstract: A reproduction and/or recording device for optical recording media which is compatible in respect of varying storage density, despite an interdependence between pit or domain size, and the light spot size. Use is made of a track guidance signal generation device which can be changed over according to the storage density type and is connected to a detector which can be used for recording media of varying storage density, i.e. in the form of the standardized CD, minidisk or MOD, and for optical recording media, which have a comparatively higher information storage density, or smaller track spacings and smaller dimensions of the pits or storage structures.

Abstract: In the case of a motor controller for electronically commutated DC motors, an additional current and/or an additional voltage is passed at the commutation instant to that winding of the motor which is active at that time, in order to prevent torque drops. In order to compensate for torque drops at different motor loads, the duration and/or amplitude of the additional current and/or of the additional voltage are/is determined from the actual motor load.

Abstract: Components for analog or digital input signals are in each case connected by switchable means to a controllable oscillator. The switch condition of the switchable means is set automatically and/or manually as a function of the input signal.

Abstract: Equalizers, used for equalizing distorted signals, are calibrated with the aid of the so-called "eye" pattern on the oscilloscope. Data bits are traced with their edges above one another by triggering to the amplitude so that an "eye" opening is produced. The "eye" is wide open and sharply delimited in the case of correct equalization. However, this method does not provide for automatic calibration of the equalizer. In order to automatically calibrate an equalizer in an optimal manner, a Lissajous figure is formed from in each case of two successive samples of the signal to be equalized. A fuzzy logic control loop compares the Lissajous figures generated with a circle in the case of a sine oscillation and with a square in the case of a square wave oscillation. From this comparison, the fuzzy logic control loop derives the parameters for the equalizer. The equalizer is optimally calibrated when a circle or, respectively, a square is formed as Lissajous figure.

Abstract: When a power supply unit supplies power to a plurality of power amplifiers, an appreciable power loss is produced in the power supply unit and in the amplifiers. According to the present invention, the output voltage of the power supply unit is regulated so that it is high enough at any instant for the amplifier which at that instant has an output signal having the largest amplitude.

Abstract: An optical scanning device having a holographic optical element for receiving a scanning beam which has been influenced by a recording medium. One aspect of the invention is to use an optical spatial filter to obtain the information signals. A further aspect is to image the entire area of the scanning spot on only one detector and to use the complete light component, as a result of which the power component is increased and the requirements for adjustment of a plurality of elements with respect to one another are reduced.

Abstract: To reduce the time required to access serially transmitted teletext data, such data is often stored in memory. The present invention reduces the otherwise required memory size by storing the characters in proportional form and/or with duplicated characters not stored a plurality of times but stored with information on the number of times a character is duplicated.

Abstract: A tuner is used in common for both terrestrial and satellite television reception. A second mixing stage is switched as a mixer for signal conversion into a second intermediate frequency during terrestrial television reception and is switched as a component of a FM-PLL demodulator during satellite television reception. The tuner is particularly suitable for television receivers and video recorders which receive signals from both a terrestrial antenna/signal source and from a satellite antenna/signal source.

Abstract: A television receiver providing a stable image whether or not a composite color signal is present, in which a transmitter-recognition processes the television synchronization signals of the composite color signal. A character generator displays alphanumeric as well as graphic characters. The deflection generators and the character generator are operative with TV signals as well as characters that are alphanumeric as well as graphic. The deflection generators and the character generator are driven by control signals. An oscillator controls the deflection generators, and a phase comparator operates in the presence of synchronization signals to synchronize the oscillator. The phase comparator receives no signals from the input terminal when no synchronization signals are present, so that the oscillator oscillates at a fixed preadjustable frequency to provide a stable image.

Abstract: A cassette for use with a recording apparatus comprises: a housing for a recording medium, the housing having a first surface and side walls, the recording medium being accessible through one of the side walls; at least a part of a chip card affixed to the housing, forming a second surface of the housing and closing the cassette, the chip card part having a memory formed integrally therewith and externally accessible contacts; and, the contacts of the chip card being positioned on the second surface to be engageable by corresponding contacts in the recording apparatus when the cassette is inserted therein. One of the side walls has an access door for the recording medium and the second surface forms an upper wall of the housing as defined by the access door. The part of the chip card forming the second surface of the housing has a marking position at which light transmissivity can be controlled. The marking position can be rendered non transmissive to light to prevent recording.

Abstract: A system for guidance of an optical scanning device is disclosed in which a gain factor (G factor) is responsive to a track error signal which is a function of the deflection of a scanning device. Deviation of the G factor setting from an optimum setting is automatically determined in conjunction with an open track control loop by driving a servo device (SV) to deflect an actuator from its neutral position and by evaluating a push-pull signal (PPTE). The G-factor is automatically set to an optimum value.

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 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: An apparatus for the transmission and reception of block coded discrete cosine transformed digital video signal having coefficients representing a DC component and a plurality of AC components of various importance. A means responsive to the digital signal separates and stores like components of the transformed digital signal. The like components are assembled into segments which define a portion of a picture. Addresses of the segments are generated and added thereto. The segments are modulated for transmission by a modulating means. Upon reception the modulated segments are demodulated by a demodulating means. The like components of segments are stored responsive to the addresses. A means, coupled to the storing means and responsive to the addresses, reconstructs from the like components, the block coded discrete cosine transformed digital video signal.

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: 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: 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: 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.