Abstract: Disclosed is an information recording/reproducing apparatus which uses a rewritable recording medium having a sector structure, and in which a data writing gate signal and a data erasing gate signal are reproduced on the basis of an ID detection signal of a target sector, while a data reading gate signal and a marking gate signal are produced on the basis of the ID detection signal of the target sector or on the basis of an ID detection signal of a sector located N sectors before the target one, so that when data is to be renewed in a specific sector from which no ID detection signal can be obtained, marking is performed in the specific sector on the basis of an ID detection signal of a sector located N sectors before the specific sector and new data are rewritten into a substitutive sector, whereby it is possible to perform data erasing and data recording in a target sector with high reliability and high positional accuracy and it is possible to shorten gaps respectively in front and rear of a data field to

Abstract: A magnetic recording/reproducing apparatus for magnetically recording and reproducing information on and from a magnetic tape. The apparatus includes a rotary drum adapted to be rotatable about its own axis and having at its circumferential portions a plurality of magnetic heads including at least first and second signal recording/recproducing magnetic heads and one signal erasing magnetic head. In order for coupling between the plurality of magnetic heads and a recording/reproducing circuit of this apparatus, further included is a rotary transformer which is provided between the rotary drum and a stationary portion of this apparatus and which includes first and second transformer coil assemblies coupled to the first and second magnetic heads, respectively, and one erasing coil assembly coupled to the erasing magnetic head. The erasing coil assembly is disposed between the first and second transformer coil assemblies to assume a magnetically neutral position with respect thereto.

Abstract: A method and an apparatus for recording and reproducing a PCM audio signal either alone or together with a video signal, using a rotary-head type scanner. An analog audio signal is converted into a digital signal having a predetermined number of quantization bits in each predetermined sampling period. The digital signal is recorded on a recording medium such as a magnetic tape, and an analog audio signal is reproduced from the digital signal reproduced from the recording medium. In the reproducing mode, the signal reproduced from the tape is written into a memory where error detection, correction and deinterleaving are carried out, and the signal is then read from the memory and applied to a D/A converter. The write rate from the memory depends on the video field period, and the read rate depends on the sampling period. Accordingly, the difference between the write address and the read address of the memory depends on the difference between the field period and the sampling period.

Abstract: A demagnitizing apparatus erases, track by track, wide-band and high-frequency recorded signals such as signals which are frequency-modulated (FM) with video signals, and thus eliminates the need for a relay to switch a single magnetic head between erasing capability and recording or reproducing capability.

Abstract: A magnetic disk drive channel circuitry is shown and described that generates eight incremental values of write current and eight incremental values of delta-V (the minimum voltage change per unit time which tests signals to discriminate between data and noise). Each of these variable parameter values may be program selected by a three bit bus signal. This variability testing of an adaptation to the optimum parameter value for each head media combination and by grouping tracks in contiguous data bands, the parameters may be optimized for tracks near the inner diameter, the outer diameter and in the middle band. The variable delta-V can also be used as an additional data recovery tool wherein re-reading with a lower value enhances recovery of missing bit errors and re-reading with an increased value can assist recovery from an extra bit error.

Abstract: An audio signal recording/reproducing system is used in a time-lapse video tape recording device for time-lapse recording a video signal on a magnetic tape at predetermined time intervals. The audio signal recording/reproducing system comprises a memory which stores an audio signal and time-compresses the stored audio signal to output it as the time-compressed audio signal at one field period, and a magnetic head for recording the one-field period audio signal on the magnetic tape. Each of the audio signal recording tracks recorded on the magnetic tape is arranged between two adjacent video signal recording tracks. The audio signal recorded on the magnetic tape is read out by the magnetic head and stored in the memory again. The audio signal stored in the memory is expanded in its time-base to be reproduced as continuous sound.

Abstract: This invention relates to an information signal recording apparatus which can be used also as an audio tape recorder only. When it is used only as the audio tape recorder, an audio signal is sampled with a frequency m times the sampling frequency of an audio signal which is used upon recording a video signal and the thus sampled PCM digital audio signal is diffusively recorded on at least two recording intervals thereby to improve the tone quality of the audio signal and the compatibility with the audio tape recorder using a video tape recorder of the same kind can be established.

Abstract: A write circuit for a streaming cartridge tape drive provides a substantially constant and symmetric write current to the magnetic write heads in the drive. The write current is provided by a pair of transistors coupled to the write head and the magnitude of the write current is maintained substantially constant by an operational amplifier coupled to the two write current transistors which regulates the voltage at the emitters of the two write current transistors.

Abstract: A memory unit adapted for use with an electronic computer or the like. In the unit, a data-clock pulse train regenerated by a head is discriminated into a data pulse train and a clock pulse train by a first discrimination circuit in accordance with a first gate signal outputted from a first gate circuit, and any error in each of such discriminated pulse trains is detected by a first regeneration error detection circuit. Meanwhile, the data-clock pulse train is discriminated into a data pulse train and a clock pulse train by a second discrimination circuit in accordance with a second gate signal which is outputted from a second gate circuit in accordance with the regenerated data-clock pulse train and is different in waveform from the first gate signal, and any error in such discriminated pulse trains is detected by a second regeneration error detection circuit, so that any regeneration error in the data-clock pulse train can be detected with a higher precision.

Abstract: A magnetic recording and reproducing apparatus wherein mechanical deteriorations and induced noises can be eliminated and detection signals different in recording density can be read by a reading circuit without a misoperation. The apparatus comprises a filter circuit including a switching element for changing over between different impedance elements in order to allow reproduction from a magnetic medium which is recorded in a recording period which is different from recording and reproducing characteristics of said magnetic head. Preferably, the switching element is a field effect transistor.

Abstract: A ferrimagnetic medium is locally heated above its compensation temperature and a magnetic record head provides a magnetic field for data recording on the heated portion of the medium. Upon re-cooling to the compensation temperature, the recorded signal is magnetically "locked" in the medium. The user of a magnetic head to provide the recording magnetic field allows fast head current switching rates with attendant high density data recording or high speed erasure of the medium. The recorded medium is read by means of conventional magneto-optic apparatus.

Abstract: An information recording and reproducing apparatus records and reproduces information on and from an optical recording disk having a sector recording format of frame structure in which data in each sector are divided into a plurality of frames, and a data head identification mark is affixed to the head of each of the frames, so as to prevent propagation of a demodulation error due to failure of word synchronization attributable to pull-out of a PLL during data reproduction. In the apparatus, one frame pulse is generated for each of the frames on the basis of a sector identifier detection signal and a frame data demodulation start signal, and, according to the result of counting the frame pulses, the frame numbers of frame data demodulated and stored in a sector buffer memory are accurately detected.

Abstract: In a PCM (pulse code modulated) audio signal recording and/or reproducing apparatus, a scanning track formed by one scanning of a tape by a rotary head is divided into a plurality of track areas in its longitudinal direction to thereby form multi-channel segment track areas, and the PCM audio signal is recorded on and/or reproduced from the segment track area of each track corresponding to a particular channel on the tape. When a plurality of programs or events are sequentially recorded in a timer scheduled recording mode, it is possible to select either a series recording mode in which successive events are recorded only in the segment track areas of one channel or a parallel recording mode, in which the successive events are recorded in segment track areas of different channels, respectively.

Abstract: Track misregistration between a read-back head and a previously recorded pair of tracks can cause erroneous data to be detected by the read head. It has been discovered that a prior erasure to eliminate any residual magnetization reversals occurring between and along side of the two parallel data tracks in twin track vertical recording can unexpectedly increase track misregistration tolerance by several hundreds of percents over the tolerance exhibited by twin track vertical recording having no pre-write erasure in the space between tracks and along side of the tracks. The erase before write technique may be practiced with a new read-write head structure having an E-shaped erase core aligned with the twin track read-write head and insulated from it to precede the read-write structure in the direction of relative motion between the read-write head structure and the magnetic medium.

Abstract: A system for data transfer includes a plurality of disks each having surfaces divided into sectors in which data may be stored; drive mechanisms for rotating the disks; a plurality of data transfer heads, one transfer head associated with each disk surface; sector determining circuitry for determining the current sector of each disk surface relative the associated head; and control circuitry responsive to the sector determining circuitry, for initiating transfer of data between the head and the associated disk surface whenever the head for that surface is at the beginning of any sector involved in the data transfer. The system further includes a memory; and a data bus coupled to the memory; a buffer coupled between each of the heads and the data bus.

Abstract: A device for dynamically indicating relative wear in a magnetic tape cartridge in which a specially identifiable signal is recorded on a separate track from that used for normal recording. Upon playback, the specially identifiable signal is recovered and compared with a "clean" reference signal to provide an error signal indicative of the amount of flutter present. The error signal sequentially activates an array of LED's to provide a relative, easily interpreted indication of the amount of flutter and hence of the extent of wear in the tape and cartridge.

Abstract: An amplifier for voltage biasing and amplifying the signals produced by a magnetic sensor is provided. Electrically, the resistance of the sensor is disposed between the bases of a differential pair comprising the input stage of the amplifier. Constant bias voltage for the sensor is provided independently of sensor resistance. DC feedback to the input stage balances current flow in both paths of the differential input stage to correct for DC offset arising in the output from input stage emitter resistor. The amplified signal, representing .DELTA.R.sub.h /R.sub.h, is sensed as a voltage across the magnetoresistive sensor, where .DELTA.R.sub.h is the change in steady-state resistance, R.sub.h, of the sensor.

Abstract: An electric control system for an apparatus for writing and reading data on and from a flexible magnetic disk under the control of host equipment such as a central processor unit having an associated controller. The control system includes a time setting circuit responsive to stepping pulses, by which the magnetic head is transported from track to track on the disk, for determining an access time to be elapsed from the moment the head starts to be transported from any track on the disk to any other track thereon to the moment the head becomes stably positioned on the new track. Connected to the time setting circuit is an index pulse suppressor circuit which suppresses any index pulse, indicative of the rotation and angular position of the magnetic disk, that is generated during each access time and which permits the delivery to the host equipment of the subsequent index pulses that are generated after the lapse of the access time.

Abstract: In a multitrack motion analyzer in which video information representing a scene is recorded at a fast frame rate and played back at a slower frame rate, digital data timing and synchronization signals relating to each recorded frame is simultaneously recorded on a separate track as bipolar return to zero (BRZ) FM signals. A Non Return to Zero (NRZ) bit serial digital data signal and synchronous data clock signal are encoded as BRZ digital data signals and then frequency modulated so that the "1" bit, the "0" bit, and the "return to zero" signal levels of the BRZ data signal are converted to three frequencies. The three frequencies are integral multiples and synchronous to the data rate of the NRZ digital data signal so as to eliminate uncertainty between bit boundaries and allow packing more bits per unit time for a given carrier bandwidth. Additionally, accurate synchronization information is recorded and recovered by inserting a missing clock in the BRZ data stream.

Abstract: A recorded data reproducing apparatus according to the invention includes a memory section having a gain data table for storing gain data determined in accordance with a cylinder position above a recording medium. Using the data representing the current cylinder position, the optimum gain data is determined from the gain data table, and supplied to a read pulse generator section under control by a control section. With this arrangement, the gain adjusting circuit is simplified, and the gain adjustment process is also simplified.