Abstract: A holding arrangement for a record storage medium includes a holding member, a housing with an aperture therein for loading the record storage medium into the holding member and removing it therefrom, and a closure member which is supported on and spring coupled to the holding member so as to be movable therewith to close the loading aperture when the holding member is moved from a loading condition to an operating condition. Movement of the holding member to a loading condition causes the closure member to open the loading aperture. The spring coupling permits a degree of freedom of movement of the closure member so that correct positioning thereof is not dependent on the accuracy of positioning of the holding member.

Abstract: A magnetic field sensor has a substrate on which a plurality of resistive elements form a double Wheatstone bridge circuit, at least one of the resistive elements in each bridge having a magneto-resistive characteristic. The two bridges are identical except in that, if a given magneto-resistive element in a given branch in one bridge has a positive output polarity, then the corresponding magneto-resistive element in the same branch in the other bridge will have a negative output polarity. By adding the output signals of the two Wheatstone bridges a zero-point offset of the sensor can be determined and eliminated. There is no need to employ the so-called flipping technique employed for that purpose in conventional sensors, which requires increased power consumption.

Abstract: Power and data are both transmitted over a single transmission line to which a power source and a number of stations are connected. A bipolar AC voltage is supplied to the line by the power source, the half cycle pulses of one polarity being used for supply of power only, while transmission of data is achieved by modulation exclusively of the half cycle pulses of the other polarity. High power is supplied to the stations by providing pulses of the one polarity at a low ohmic level. Only low power is required for modulation for the purpose of data transmission, and so the pulses of the other polarity are supplied at a relatively high ohmic level. Thus, only two conductors are required, one of which can be replaced by the system ground in the simplest case. If three conductors are provided, it is possible to achieve improved tolerance of defects in a conductor.

Abstract: A disc-shaped information carrier and a device for reading and/or writing information blocks in a track thereon which follows a helical or concentric path forming successive windings. For identifying each winding the information carrier also has a servo pattern thereon which includes position-information as well as synchronization elements. Such elements may be, for example, brief pulses in a continuous track wobble, and are distinguishable in adjacent windings based on a predetermined detectable parameter, such as alternating polarity or shifted relative phase positions. The device has a read/write head and a system control which during writing detects the synchronization elements and monitors whether a deviation has occurred signifying that the read/write head has wandered to an adjacent winding. In that event writing is interrupted. Thus, the least possible information in adjacent windings is overwritten in the case of disturbances resulting from shocks or defects of the information carrier.

Abstract: A device in which an elongate material which can be wound in the form of a roll is driven in a transport direction. The device has tension control means for controlling the tension in the material when the material is driven, which tension control means comprise a flexible braking member which is passed around a braking drum. The braking member is formed by a coil spring which has two spring arms, one of which is movable in order to influence the braking force of the coil spring in dependence on the instantaneous tension in the material.

Abstract: In a harmonic speech encoder (16) a speech signal to be encoded is represented by a plurality of LPC parameters which are determined by a LPC parameter computer (30), a pitch value and a gain value. The speech encoder comprises a (coarse) pitch estimator (38) for determining a coarse pitch, and a refined pitch computer (32) to determine a refined pitch from the coarse pitch value. The refined pitch value is determined in an analysis by synthesis way, in which a refined pitch value is selected which results in a minimum error measure between a representation of a synthesized speech signal and a representation of the original speech signal.

Abstract: An audio bitstream is read from a digital video disc DVD for transfer, subsequent to parsing thereof, via an IEC 958 protocolled interface, for use in a multi-channel audio reproduction apparatus. For each respective audio channel MPEG audio samples are packaged recurrently in burst payloads, and these burst payloads are packaged as user data in IEC958 format frames. Pause bursts are used for signalling absence of audio for all associated channels with, each pause burst representing such audio absence during a perceptibly acceptable time interval only.

Abstract: The invention relates to a brushless d.c. motor having a commutation circuit for the commutation of phase currents in order to generate a given commutation angle in a given mode of operation of the d.c. motor. In order to guarantee a satisfactory performance of the motor for all modes of operation the commutation circuit is switched between a plurality of modes in which different commutation angles are generated with a switching frequency which is substantially higher than the operating frequency of the motor. The invention is particularly suitable for the use in brushless d.c. motors for domestic appliances such as food processors.

Abstract: An angle sensor includes a lateral magnetic field sensor element (1) for producing a sensor signal (U.sub.S) which is dependent on the angular position of a target object (6) which is rotatable about an axis of rotation (5). The lateral magnetic field (8) is produced by a magnet (4) which also produces an axial magnetic field (7). Magnetic field sensor elements have a linear characteristic only over an angular range of up to at most 180.degree.. According to the invention, however, in addition to the field sensor element (1) there is also provided a measuring element (2) which determines the direction of an axial magnetic field (7) also produced by magnet (4) and which traverses the measuring element (2). An evaluation circuit (9) is thereby enabled to determine the angular position of the target object (6) from the sensor signal (U.sub.S) produced by the magnetic field sensor element (1) and the direction signal (U.sub.

Abstract: Method is described of reducing particle contamination during sputtering and sputtering device for the implementation of such a method.A method of providing a layer on a substrate (1), whereby, during a certain process time, material (8) is detached from a target plate (6) through a bombardment of this target plate with ions from a gas discharge (4) under reduced pressure in a reactor chamber (2) which is provided with a support (7) for the substrate (1). Measures are taken to ensure that material deposited on a surface of chamber component (9) near the support (7) has a better adhesion. According to the invention, the measure for achieving a better adhesion of the material consists in that the surface of the chamber component (9) is first bombarded with ions from the gas discharge (4) for at least part of the process time.

Abstract: A housing for storing disc-shaped information carriers, for example CD's, has a central part (14), two identical lid parts (10, 11), and a support plate (15) which extends from the central part and is situated between the lid parts. In order to increase the available space within the housing, the support plate (15) is flat on both sides and is asymmetrically positioned between the lid parts (10, 11) so as to form two spaces (17, 18) of different sizes between the lid parts and opposite sides of the support plate. Such spaces can accommodate information leaflets of different thickness.

Abstract: A digital transmission system provides selective protection by combining a convolutional coding, a punctured coding and a digital quadrature amplitude modulation. The rate of the convolutional coding in N/2N and the modulation uses a 2.sup.2N -point constellation, with N>1.

Abstract: Apparatus having a wall and a button arranged in an area of the wall, button actuating means, a switch which is remote from the button actuating means, switch actuating means, and transmission means arranged between the button actuating means and the switch actuating means. The button actuating means is formed by a bell-crank lever which is pivotable about a pivot which is displaced toward the switch in a direction parallel to the wall of the apparatus. The transmission means is formed by a transmission bar supported so as to be movable at least substantially in a direction parallel to the wall and which extends substantially in that direction.

Abstract: A digital communication system including a transmitter and a receiver and wherein transmitted digital signal samples are modulated in accordance with a first constellation of modulated signal values. The receiver includes a phase locked loop for synchronizing digital sampling at the receiver with the received signal samples. The synchronism adjustment error is formed from a pseudo-error function which is a weighted combination of first and second errors, the first error being a function of the distance between received samples and the decisions made with respect thereto in the first constellation, the second error being a function of the distance between received samples and the decisions made with respect thereto in a second simplified constellation derived from the first constellation. A weighting is assigned to the second error which may, in one embodiment, be proportional to the first error.

Abstract: A read device for reading a record carrier which has recorded thereon a data signal which represents data words, added codewords of a first type and added codewords of a second type. The added codewords of the first type have a predefined first relation to the data words, and the added codewords of the second type have a second predefined relation to the data words and the added codewords of the first type. The added codewords of both types enable error correction according to a given algorithm. The data signal is divided into blocks which each contain a control portion which includes control words and a data portion which includes user-supplied data words. The data words and added first and second type codewords are ordered and interrelated so that the order of the data words is not altered by error correction according to the given algorithm, and the second-type codewords are located closer to the related control data words than are the first-type codewords.

Abstract: A data compression apparatus for data compressing a digital information signal obtained from a digital audio signal. The digital information signal includes p-bit samples, where p is an integer larger than 1. The apparatus has an input (16) for receiving the digital information signal, and a lossless compression unit (18) for carrying out a substantially lossless compression step on the digital information signal so as to obtain a data compressed digital information signal. The lossless compression unit includes a Rice encoder, which is distinguishable by a code parameter m. Further, an output terminal (22) is available for supplying the data compressed digital information signal. The Rice encoder has a generator unit (30) for generating the code parameter m from N samples of the digital information signal, in accordance with a formula which optimizes the value of m for each frame of N samples.

Abstract: In an interactive audio-video digital distribution system a pointer is transmitted at least once every T milliseconds to indicate the position of a time marker. An interruption (V) occurs every T milliseconds. A given number N of integer frames being transmitted in T milliseconds, there remains only space for transmitting a portion containing R symbols of the N+.sup.th frame before the next interruption. Following transmission of a signaling packet (x) with a pointer indicating a number (x) of symbol periods, during the next interruption N packets will have been completely transmitted since the last pointer, plus R symbols. The end of the transmission of this packet is waited for, that is, U.dbd.C-R symbol periods before a new signaling packet (x-U) is transmitted. The value of the pointer contained in this packet will thus have to take this offset into account as it is decremented by U symbols, that is, x-U, and so on.

Abstract: An information storage system is described which comprises a reading device (6) and an optical record carrier (5) having at least two information planes (1, 2, 3). The radiation from the record carrier is converted in a detection system (15) into a detection signal (16) which is applied to a detection circuit (17). In order that this circuit can derive the read information from the detection signal in a reliable manner, the interference signals generated by the information planes which are not to be read should comply with a requirement, referred to as the interference requirement, which is characteristic of the detection circuit. Values for the parameters of the record carrier, such as the thickness of the layers between the information planes and the reflection and transmission coefficients of the information planes then follow from this interference requirement.

Abstract: An amplifier having an inductive coupling (LL) via which a load (Z1) may be coupled between the two main current terminals (E,C) of a transistor (QA). A capacitive coupling (CC) is also provided between the two main current terminals (E,C). The inductive coupling (LL) and the capacitive coupling (CC) provide, between the two main current terminals (E,C), respective impedances (ZLL, ZCC). To achieve a satisfactory performance in terms of signal distortion and gain, impedances (ZLL, ZCC) are substantially equal in magnitude in at least a portion of a frequency range throughout which the amplifier provides gain. The amplifier is particularly suitable for cable-network applications.

Abstract: A signal processing method and apparatus are described for demultiplexing selected components (especially audio signals) from a multiplexed data stream. Each of the desired channel components has a unique identification code detected by a processor parsing the contents of a received data buffer between the disc reader and the demultiplexer. The demultiplexer is set up to output received data channel streams having a specific identification code different from any of those assigned to the channel streams originally. Prior to demultiplexing, the identification code for a desired one of the channel streams is altered by the processor to the specific identification code as it passes through the buffer in order to avoid re-setting the demultiplexer.