Abstract: System for recording and/or reproducing information, medium for use in the system, and magnetic write head for formatting the medium. The invention relates to a system including a magnetic tape (310) formatted by way of a write head (360), and an apparatus incluiding a magnetic head unit (320) which is movable on a transverse direction (y) by way of an actuator. By way of the write head (360) the magnetic tape (310) has been provided with a pattern of servotracks ST101-ST127 which extend in a longitudinal direction (x). The odd-numbered servotracks contain a first servosignal and the even-numbered servotracks contain a second servosignal Sb which is phase opposition to the first servosignal. The servotracks ST103-ST113 and ST116-ST126 have a typical width W1 and form a group of two bands of N1 servotracks which are separated by a band of N2 servotracks ST114, ST115 having a typical width W2. The magnetic tape (310) is provided to cooperate with an apparatus including eight magnetic write heads (H31-H38).

Abstract: An arrangement for recording servo signals on a magnetic tape has first and second adjoining write heads respectively driven by first and second write signals. Each write signal includes a servo signal and a bias signal, the bias signals being phase displaced periodic signals which result in the magnetic tape being magnetized alternately by the first and second write heads. This provides a sharp transition in the servo signals produced from adjoining servo tracks during read-out.

Abstract: A servosystem for controlling the position of a magnetic head with respect to the tracks of a magnetic recording medium which is relatively movable with respect to the head and has a plurality of juxtaposed tracks, including a read head for simultaneously reading information signals and servosignals stored in the tracks, the read head having a head face and a layer structure comprising parallel read units, each having a read gap and extending substantially transversely to the head face, the read gaps of two adjacent read units each extending between a magnetically conducting common pole terminating in the head face and an individual pole terminating in the head face.

Abstract: The invention relates to a comprising a magnetic tape formatted by a write head, and an apparatus comprising a magnetic head unit which is movable on a transverse direction by an actuator. The write head records the magnetic tape with a pattern of servotracks ST101-ST127 which extend in a longitudinal direction. The odd-numbered servotracks contain a first servosignal and the even-numbered servotracks contain a second servosignal Sb which is phase opposition to the first servosignal. The servotracks ST103-ST113 and ST116-ST126 have a typical width W1 and form a group of two bands of N1 servotracks which are separated by a band of N2 servotracks ST114, ST115 having a typical width W2. The magnetic tape is adapted to cooperate with an apparatus comprising eight magnetic write heads. The actuator is controlled in response to the servosignals read by the heads. The center-to-center distance between the magnetic write heads is equal to four times the typical width W1 and, moreover, it holds that:N2=2, 4, 6 etc.

Abstract: A write head, particularly a buried servowrite head provided with a head face (21) having a longitudinal direction (L) along which a magnetic recording medium can be relatively moved with respect to the magnetic head, and a width direction (W) oriented transversely to the longitudinal direction. In order to write signals simultaneously in various tracks, the write head is provided with a structure having integrated, juxtaposed write units (25a; 25b) extending substantially transversely to the longitudinal direction and the width direction and each being provided with at least one write gap (27a; 27b). One write gap of the one write unit and one write gap of the other write unit of every two adjacent write units are situated in mutually different planes (P1; P2) which are oriented substantially transversely to the longitudinal direction.

Abstract: A system and method for recording and reproducing information includes a magnetic tape, a magnetic-head unit and an actuator. The magnetic tape has servo tracks containing servo signals. The servo signals have been written with a magnetic head, not shown, having a comparatively large gap length. As a result, the servo signals are recorded deep into the magnetic tape. The magnetic-head unit comprises a read head and a write head to inscribe the track, the read head following a bounding line between adjacent servo tracks and in response to the servo signals read from said servo tracks and by the read head. The system in accordance with the invention is characterized in that it comprises control means which determine the sequence in which the information tracks are written, the read head either following a track or between two respective non-overwritten parts of the magnetic tape, or following a track or between two respective overwritten parts of the magnetic tape.

Abstract: A method and an apparatus are disclosed for recording a binary signal onto a magnetic record carrier. The binary signal is supplied to an input terminal. The apparatus comprise generators for generating at least two write pulses (P.sub.1,P.sub.2) for each bit of the binary signal to be written. More specifically, the generators are adapted to(i) generate at least two write pulses of a third polarity for the first bit of the first polarity in the first sequence,(ii) generating a write pulse of the third polarity and a write pulse of a fourth polarity for the at least second bit of the first polarity occurring in the first sequence, the third polarity being opposite to the fourth polarity,(iii) generating at least two write pulses of the fourth polarity for the first bit of the second polarity in the second sequence,(iv) generating a write pulse of the third polarity and a write pulse of the fourth polarity for the at least second bit of the second polarity occurring in the second sequence.

Abstract: The invention relates to a system for recording and/or reproducing information, comprising a magnetic tape and an apparatus comprising a magnetic head unit which is movable on a transverse direction by means of an actuator. By means of a write head, the magnetic tape has been provided with a pattern of servotracks ST101-ST127 which extend in a longitudinal direction. The odd-numbered servotracks contain a first servosignal and the even-numbered servotracks contain a second servosignal which is phase opposition to the first servosignal. The servotracks ST103-ST113 and ST116-ST126 have a typical width W1 and form a group of two bands of N1 servotracks which are separated by a band of N2 servotracks ST114, ST115 having a typical width W2. The magnetic tape is adapted to cooperate with an apparatus comprising eight magnetic heads. The actuator is controlled in response to the servosignals read by the heads.

Abstract: A magnetic tape apparatus intended for consumer use includes at least one digital head with nine digital transmission gaps for reading and/or writing compressed digital information in longitudinal tracks on a magnetic tape. The apparatus also includes electronic circuitry for compressing the digital information prior to writing, and for expanding the digital information after reading. This arrangement enables at least playback of digital audio information at the same frequency used for analog compact cassettes, so that inclusion of an analog head enables playback of analog compact cassettes as well.

Abstract: An apparatus is disclosed for positioning a head relative to a plurality of tracks running parallel to each other in their longitudinal direction on a record carrier. The apparatus comprises a position detection unit for detecting the position of the head in a transverse direction, which has an output for supplying a first and a second position signal when the head is positioned onto each of two tracks. A memory is present for storing the first and second position signals. In a calibration mode of operation, a control signal generator generates a control signal to position the head onto one of the tracks and the memory stores the position signal generated by the position detection means. The control signal generator subsequently generates a second control signal so as to position the head onto the other track. The memory stores the second position signal generated by the position detection means.

Abstract: Digital information recorded in a track (T.sub.a.i) on a tape-like magnetic record carrier (20) can be read out again when the record carrier is transported in a specific direction. The transport direction of the record carrier when the information is recorded may be similar or opposite to the direction in which the information is reproduced. This implies that as a function thereof a first or second equalization filter (F.sub.1, F.sub.2) is to be used during reproduction so as to realise a first or second filtering of the information that is read out. For this purpose, markers (M.sub.1, M.sub.2) are introduced on the record carrier (20) or the cassette (61). From these markers there may be derived whether the side being read out at a specific moment has been recorded in a transport direction similar or opposite to the transport direction during reproduction.

Abstract: Transmission system for transmitting and receiving, and subband encoding methods for generating for transmission, digital signals containing modulated bit allocation information; and record carriers containing such a signal. The transmission system include a transmitter which encodes in accordance with the subband encoding method a wide-band digital signal into subband signals which are each made up of successive signal blocks having a predetermined number of samples of that subband signal. The samples in the signal blocks of the subband signals are quantized to produce quantized samples in the signal blocks, and bit allocation information denoting how many bits the samples in the signal blocks are to be quantized by is generated. The bit allocation information (or a portion thereof) is modulated to obtain modulated bit allocation information.

Abstract: A device for recording an information signal on a magnetic record carrier (2) includes a write amplifier (3), a magnetic head (4) of the magnetoresistive type, and a compensation circuit for controlling the amplitude of the write current in dependence upon temperature variations which occur during recording. The compensation circuit includes an actuator for bringing the record carrier into contact with the magnetic head (4) before a recording is started. In addition, detector means (17, 18) is provided to detect an output signal of the magnetic head produced as a result of the magnetic head being brought into contact with the record carrier. A control signal generator (17) generates a control signal whose magnitude is a measure of the magnitude of the output signal. The compensation circuit (3, 5, 8, 11, 17) is adapted to control the amplitude of the write current in dependence upon the control signal.

Abstract: Transmission system, and transmitter and receiver for use in the transmission system for transmitting and receiving digital signals containing modulated bit allocation information. The transmitter encodes a wide-band digital signal into subband signals which are each made up of successive signal blocks having a predetermined number of samples of that subband signal. The samples in the signal blocks of the subband signals are quantized to produce quantized samples in the signal blocks, and bit allocation information denoting how many bits the samples in the signal blocks are to be quantized by is generated. The bit allocation information (or a portion thereof) is modulated to obtain modulated bit allocation information. The quantized samples in the signal blocks and the modulated bit allocation information are included in a digital signal applied by the transmitter to a transmission medium. The receiver receives a replica of the digital signal applied to the transmission medium.

Abstract: Digital information recorded in a track (T.sub.a.i) on a tape-like magnetic record carrier (20) can be read out again when the record carrier is transported in a specific direction. The transport direction of the record carrier when the information is recorded may be similar or opposite to the direction in which the information is reproduced. This implies that as a function thereof a first or second equalization filter (F.sub.1, F.sub.2) is to be used during reproduction so as to realise a first or second filtering of the information that is read out. For this purpose, markers (M.sub.1, M.sub.2) are introduced on the record carrier (20) or the cassette (61). From these markers there may be derived whether the side being read out at a specific moment has been recorded in a transport direction similar or opposite to the transport direction during reproduction.

Abstract: The audio signal is divided into frequency sub-bands, the sub-band samples are quantized according to a predetermined quantizing criterion, and the quantized samples in one or more sub-bands are summed with samples of the auxiliary signal in such sub-bands, the auxiliary signal sample in a sub-band having a maximum amplitude less than half the quantization step used in such sub-band. The combined signal, covering the entire frequency band of the audio signal, can be transmitted or recorded on a record carrier. Upon audio reproduction at a receiver only the audio signal will be audible, the auxiliary signal being masked due to the psychoacoustic characteristics of the human auditory system which are unresponsive to low-level noise in the presence of high amplitude sound. The receiver includes a decoder which analyzes the combined signal into the original frequency sub-bands and re-quantizes the sub-band signals using the same quantizing criterion as at the coder.

Abstract: Low-frequency components of the left and right channels of the audio signal to be recorded are derived by means of filters (3, 4). First and second auxiliary signals are added to such low-frequency components in such a way that during reproduction of the audio signal so recorded, including the first and the second auxiliary signals added thereto, by means of two loudspeaker units arranged in a stereo configuration, the two auxiliary signals are not audible. However, they will inhibit re-recording by apparatus for recording audio signals which are not copy-protected in the form of the aforesaid two auxiliary signals, or will cause such apparatus to indicate that the audio signal to be re-recorded is protected.

Abstract: A system (1) for reproducing information signals recorded on a magnetic tape (2) in oblique tracks (S) in different modes of operation with different tape speeds v(n) includes a tape drive device (13), which is switchable in respect of the tape speed, at least one magnetic head (K1, K2), which is rotatable by a head drive device (32), which is switchable as regards the speed of rotation, and a tracking servo system (41) for guiding said head along the tracks, and including a sawtooth generator (67) whose signal waveform is variable in order to generate a sawtooth-shaped control signal. In the case of a change of mode, the tape drive device (13), the sawtooth generator (67) and the head drive device (32) are set to different operating values by a switching device (12).

Abstract: A reproducing apparatus for information signals recorded in inclined tracks together with tracking signals whose frequency changes from track to track in a cyclic sequence, comprises a variable-frequency signal generator for the generation of track selection signals, from which together with the crosstalk tracking signals reproduced during a playback mode by at least one rotatable playback head arranged on an electromechanical transducer a transducer actuating signal is derived for tracking purposes, by means of which actuating signal the transducer with the playback head is adjustable between two extreme positions transversely of the tracks.

Abstract: A control loop provided with a control unit for realizing a transfer characteristic having a number of peaks at a fundamental frequency and harmonics thereof. The control unit comprises a memory device for digitally storing a number of samples of the error signal appearing in the control loop during a cycle period equal to the period corresponding to the fundamental frequency. Furthermore, there are provided means for comparing the sample stored in the memory device with the value of the error signal one cycle period later and, depending on this comparison, correcting the memory content of the relevant memory location. The variation of the error signal stored in the memory device is furthermore cyclically employed as a control signal for the control device included in the control loop.