Abstract: Transformer comprises a core (K1, K2), a primary winding (W1) and at least one secondary winding (W2), which are arranged as conductors on one or more layers of a flat carrier, and a coil former with a chamber system having chambers (C1, C2), which accommodate the layers with the windings (W1, W2). At least one of the chambers (C1, C2) is closed at least in regions, with the result that long distances for creepage paths are obtained. As a result of this, it is possible to adhere to existing safety regulations for the mains power supply isolation even with very compact dimensions and/or with full utilization of the width available for the conductor tracks. The chamber system can be formed from two or three plastic parts (P1, P2, P3) by mating. The layers with the conductor tracks are routed laterally out of the chamber system in order to make contact with terminals.

Abstract: An apparatus for electron beam deflection in a cathode ray tube, in particular in a picture tube of a television set, comprises a deflection coil arrangement for horizontal and vertical deflection of the electron beam, an auxiliary deflection coil arrangement, by means of which the electron beam can be influenced for the purpose of convergence correction, and a compensation coil arrangement for producing a magnetic compensation field. The compensation coil arrangement is arranged and designed such that the compensation field essentially compensates for the stray magnetic field of the deflection coil arrangement in the physical region of the auxiliary deflection coil arrangement.

Abstract: An optical polarization device includes a source of light emitting a non-polarised light beam. A polarization separator reflects one polarization component of the light beam and transmits the other polarization component. A reflection means receives the component reflected by the polarization separator, rotates its polarization plane through 90.degree., and returns it to the polarization separator. The polarization separator is a plane element. The reflection means is positioned on the source side of the separator and consists of a regular network of prisms, each partially covered with a reflective layer associated with a .lambda./4 plate.

Abstract: A high capacitance mirror driver cell provides reduced photocurrent leakage and includes a metal 1 layer comprising integrated circuit elements and a metal 2 layer comprising additional integrated circuit elements, the metal 2 layer being positioned over and associated with send metal 1 layer. A metal 3 layer blocking light and forming a ground plane and a metal 4 mirror layer covering at least a portion of said dielectric material and said metal 3 layer for forming a capacitive element operating to substantially reduce the effects of photocurrent leakage.

Abstract: The invention concerns a device which comprises a device for displacing to transversely position a multitrack tape in front of a reading and/or writing head. The magnetic tape carries a plurality of elementary tracks which are grouped in several bundles. These bundles are selectively accessed using the device for displacing. The writing and/or reading head can write and/or read information from elementary tracks contained in one bundle at a time. The device for displacing comprise a tape guide acting on longitudinal edges of the tape and transversely translating the tape. Furthermore they comprise either a movable tape reels platform or movable pins to accommodate for the transverse tape displacement.

Abstract: Switched-mode power supplies having a switching transistor and a transformer, with whose primary winding the switching transistor is connected in series, usually require a starting circuit, which is connected to an input voltage. Since a current continually flows through the starting circuit even during normal operation, it is endeavoured to keep the said current as small as possible. The switched-mode power supply comprises a threshold value circuit, for example a Zener diode connected in series with a resistor, which keeps the driver circuit turned off after the switching-on of the switched-mode power supply, until the operating voltage for the driver circuit has exceeded a specific threshold value which is referred to one end of a winding on the primary side. As a result of this, it is possible to charge a charging capacitor via the starting circuit with a low current, without currents flowing away.

Abstract: In recorders, in particular video recorders, the use of various sizes of cassette is intended and is already customary. For this purpose, the size of the cassette must be identified and the hubs of the transport drive changed appropriately. A mechanical coupling between the winding adjustment and the loading drawer during the loading operation, has no influence on the winding adjustment if a large cassette is inserted, whereas the identification and adjustment, formed by a lever, come into mechanical contact with the winding adjustment in the case of a small cassette. The mechanical coupling is formed by a U-shaped lever, the position.

Abstract: In order to compensate for currents which are induced in a convergence yoke (16) by a deflection yoke (14), a pulse of current is injected into an amplifier (26) which receives the convergence waveform (from 28) so as to correct or compensate for the induced current. One way of generating the compensating pulse is by delaying a horizontal retrace pulse (36).

Abstract: Transformer (1) for switched-mode power supply, equipped with a former (6) having chambers (9), each chamber (9) containing windings (15, 16), each winding (15, 16) having an outer side surface (18) generated by a straight line moving parallel to an axis (AA') of the former, and characterized in that the generatrices of all the outermost surfaces (18) of the windings (15, 16) contained in each of the chambers (9) are identically the same for all the outermost surfaces (18) of the windings (15, 16) of each of the chambers, these generatrices thus forming a unique cylindrical surface parallel to the axis (AA') of the former (6).

Abstract: There is disclosed a high voltage transformer for a television receiver, comprising a coil former in which there are situated auxiliary windings, a primary winding over the auxiliary windings, and a high voltage winding over the primary winding. A first sleeve forms a flat base for the primary winding, and is arranged on the auxiliary windings. The primary winding is wound from a plurality of layers of solid wire, each layer disposed directly over the other, and a further sleeve made of a dielectric inserted between two of the plurality of layers.

Abstract: Run/standby switching including switching to standby upon excessive current loading are provided in a switched mode power supply useful as an auxiliary power supply in a television. A switching controller IC is coupled between a primary transformer winding on the rectified raw B.sup.+ input voltage and ground. A switching transistor is coupled to the control input of the controller and is biased by the raw B.sup.+ input voltage for pulling down the control input. A run/standby control circuit and an overcurrent protective circuit disable the switching transistor during run mode operation and enable the switching transistor upon an overcurrent fault. The switched-mode power supply is further provided with a quick-reset capability to enable the power supply to consistently provide output voltages which are within nominal output voltage levels despite rapidly repeated dislocations in the operational mode of the apparatus.

Abstract: Circuitry to control a power supply of a degaussing coil of a cathode ray tube, said degaussing coil is coupled to a main voltage supply through a switching device the circuitry has inputs coupled to a direct source of current of a switched mode power supply, the switched mode power supply comprises a switched mode transformer with primary windings coupled to the main source of voltage, and secondary windings and the switched mode power supply is switched in a first range of frequencies when the power supply is in a "standby" mode and in a second range of frequencies when the power supply is in an "on" mode wherein said circuitry comprising a detecting circuit which detectes a change in the range of switching frequencies when the power supply is switched from standby to on, the detecting circuit having an input coupled to a direct current source being downstream of a primary winding of the switched mode transformer and an output coupled to an input of a control circuit of the switching device the control circ

Abstract: A power sensor circuit for use in a convergence system which comprises a convergence circuit for generating a convergence correction signal. The power sensor circuit receives at least one supply voltage and generates an output signal having a magnitude selected in accordance with whether the at least one supply voltage is above a first threshold. The output signal is coupled to the convergence circuit, which enables or disables the convergence correction signal in response to the magnitude of the output signal.

Abstract: Electronic circuit having a digital controller operation of a synchronous motor.Precision motors for driving, for example, a video head drum in video recorders are normally designed as externally commutated synchronous motors. These motors are driven with square-wave voltages by a digital controller (CON), whose circuitry can easily be implemented.The object of the present invention is to specify an electronic circuit of the type mentioned initially for controlling a synchronous motor, which enables good synchronism and the motor to be operated with little electrical noise.This object is achieved in that the synchronous motor is driven by sinusoidal signals, a separate control signal from the controller (CON) influencing the amplitudes of the drive signals (U1, V1, W1). A regulating signal for regulating the synchronous motor is produced by a sensor (GE) which is arranged on the synchronous motor, which regulating signal produces a fixed phase relationship between rotor revolution and drive signals.

Abstract: In order to produce synchronous control signals of a video recorder, in particular of a digital video recorder, a position pulse of the scanner motor, which coincides with the beginning of the video frame, is used as time zero point. Time markers in which changes in the control signals take place are calculated starting from this time zero point. These time markers and the bit patterns occurring at these time markers are stored as data words in a data field and, for corresponding time markers, the corresponding data word is output in parallel, that is to say synchronously. A realization is possible by means of a microcontroller and a controllable output memory, the microcontroller containing the functions of capture register, timer, calculation unit and comparator.

Abstract: Deck and drum for a tape playback and/or recorder machines in which the assembly of deck and drum is made by way of lugs 19 of the drum cooperating with catch 14 of the deck. With such an arrangement the assembly of the deck and drum can be easily automated the drum being assembled by translation and then relative rotation of the deck and drum.

Abstract: A drive mechanism for driving independently a first and a second coaxial reel, uses only a single rotatable driving unit for driving both coaxial reels. Independent drive is achieved by reversing the rotation of the driving unit.

Abstract: Power amplifier circuit for an inductive load including a supply voltage applied to the inductive load via a series circuit comprising a first transistor electronically coupled to a second transistor for conducting current from the supply voltage through the first and second transistors to the inductive load, wherein a reference potential smaller than the supply voltage is coupled at a center point of the series circuit.

Abstract: A deflection yoke assembly for a cathode ray tube includes four substantially equally spaced inclined mounting members arranged about the circumference of a mounting ring at the front of the yoke assembly. Each mounting member has a plunger which positions the yoke with respect to the funnel portion of the cathode ray tube. A continuously unidirectional restricting means prevents the plunger from withdrawing from the funnel portion of the cathode ray tube. A release cylinder, which is coaxial with the sleeve and plunger, releases the unidirectional means, which may be an internally toothed washer, in order to provide capability for readjustment.

Abstract: A television receiver has a switched mode power supply controller, which may be deflection synchronized, which produces pulses in a power transformer. To power the controller during startup, before the internal power supply has started, a storage capacitor on the power supply input of the controller is coupled through a current limiting resistance to a rectified voltage from the AC mains so as to charge the storage capacitor during first polarity phases of the AC mains. The current limiting resistance includes a positive temperature coefficient (PTC) element which increases its impedance as it heats, to reduce power dissipation after initial connection of the television receiver to AC mains. In addition, a diode is coupled in a current path to the storage capacitor to charge the capacitor to the same polarity during opposite polarity phases of the AC mains.