Abstract: A recording/playback apparatus wherein rotary heads play back positional information recorded on a magnetic tape which can travel rapidly in a search operation. Piezoelectric actuators extend the rotary heads, an actuator driver drives the piezoelectric actuators, and a microprocessor controls the actuator driver. A target position on the magnetic tape is designated through a control panel by a user of the apparatus. The processor controls the actuator driver so as to hold the heads out of contact with the tape in a pause or stop mode of the apparatus, and so as to bring the heads into temporary contact with the tape at least once before the tape is caused to travel to the target position, whereupon the processor detects the positional information on the tape. When the target position has been approached, the processor controls the actuator driver so as to hold the heads in contact with the tape, and it detects the positional information.

Abstract: An information recording-playback apparatus is made up of a circuit for recording first information, which is video data or data for the evaluation of a recording medium such as a magnetic tape, on the first track formed by helical scanning of rotary heads, a circuit for recording second information such as a control signal or time code or third information on a second or third track formed by one or more fixed heads in the longitudinal direction of the tape, and switching device for selecting the operational mode in which the first information and the second or third information are recorded or the operational mode in which only the second or third information is recorded. The arrangement enables pre-formatting of only the second or third information without recording the tape evaluation information.

Abstract: A head drum apparatus includes a cylindrical piezoelectric ceramic member formed of a polarized ceramic material and having inner and outer peripheral surfaces. A plurality of electrodes are formed on at least one of the inner and outer peripheral surfaces of the piezoelectric ceramic member. The piezoelectric ceramic member vibrates in response to an AC voltage applied to the electrodes. A cylindrical stationary head drum having an inner peripheral surface and an outer peripheral surface around a portion of which a magnetic tape is wound is caused to vibrate in a bending mode under vibration of the piezoelectric ceramic member. The stationary head drum includes a cylindrical stationary portion, a cylindrical vibratory portion and a cylindrical thin wall portion provided between the stationary portion and the vibratory portion. The piezoelectric ceramic member is coupled to the vibratory portion so that the vibratory portion is caused to vibrate under vibration of the piezoelectric ceramic member.

Abstract: A digital tape recording and reproducing apparatus includes a rotary drum, a magnetic tape helically wrapped around the rotary drum, a mechanism for advancing the magnetic tape relative to the rotary drum, and a recording/reproducing magnetic head mounted on the drum which scans the magnetic tape for recording or reproducing digital signals. The digital signals are recorded in, or reproduced from, successive inclined tracks formed on the tape as the tape is advanced. During recording of the signals, a timing signal is generated at a predetermined interval of time after detection of a reference signal that represents a phase of rotation of the drum, and then the timing signal is recorded in at least one of the inclined tracks, interspersed with the digital signals recorded in the track. During reproduction of signals from the tape, the drum phase reference signal is detected and the timing signal is reproduced and detected, and the time interval between detection of the two signals is measured.

Abstract: A rotation control device including a rotary head drum drive circuit for driving rotation of a rotary head drum, a tape transport mechanism for transporting a tape in a predetermined direction relative to the rotary head drum, and a correction circuit for detecting a change of the speed of transportation of the tape to supply correction information to the rotary head drum drive circuit so that the driving state of the rotary head drum is corrected.

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: A record and play-back system for a still video device, in which a picture signal and an audio signal associated therewith are recordable on a first track and a second track of a recording medium; a first code signal and a second code signal are recorded together with the associated picture signal and the associated audio signal to discriminate that the respective picture signal and audio signal are recorded together with the corresponding audio signal or the picture signal. The second track is played back when the first code signal is recorded on the first track upon play-back of the first track. The audio signal can be post-recorded on the second track when no signal is recorded on the second track.

Abstract: A magnetic recording head positioning system includes a Terfenol-D magnetostrictive rod prestressed by a lever arm to operate in a linear range to microposition the magnetic recording head in accordance with an electromagnetic field. The mechanical advantage of the lever arm amplifies changes in the magnetostrictive rod to position the head. The varying electromagnetic field is applied to the rod by a coil in response to a position error signal produced from servo data tracks on the magnetic tape. A permanent magnet system biases the magnetostrictive element with a DC field so that varying the field provides bi-directional motion of the magnetic recording head. The DC field also reduces coil current and size requirements.

Abstract: A head base has at least one head chip fixed thereto. A position of the head chip is adjusted to a predetermined position by applying a laser beam to the head base to cause plastic deformation of the head base. Appropriate laser radiation conditions are set depending upon a necessary amount of positional adjustment of the head chip fixed to the head base.

Abstract: A disk drive in a multi-disk storage system has a spindle synchronizer and a spindle controller that are microprocessor-based. The spindle synchronizer has a counter used to track the phase of a master phase reference signal that is distributed to all the disk drives in the storage system. The counter may also optionally be used to generate the master reference signal. The spindle synchronizer also has programmable registers and a comparator that are used to generate a spindle reference signal having a programmable phase offset relative to the master reference signal, and a register used to sample the phase of the master reference once per revolution of its associated spindle. The spindle controller contains a counter used to measure the actual rotational period of the associated spindle. The spindle phase error is used in a phase correction algorithm that controls a reference voltage supplied to a motor spin controller.

Abstract: A tape run control unit in a magnetic recording and reproducing apparatus is provided with a discriminator and on a controller. The discriminator detects a stand-by time until a signal to be recorded is received in repositioning of the tape and generates a discrimination signal for discriminating the length of the stand-by time. The controller controls tape driving unit such as a capstan motor during the reposition and controls the stop position of the tape such that a magnetic head scans the portion of the tape where no data is recorded. After completion of repositioning, furthermore, the controller is responsive to a discrimination signal so as to select the stop mode which involves the release of pinch roller when the stand-by time is long and to select the mode for simply stopping only the capstan when the stand-by time is short.

Abstract: The present invention provides an apparatus and method for precise servo tracking of a multi-track magnetic tape head. The magnetic tape has at least one servo area with at least two servo tracks. Adjoining servo tracks have different servo patterns recorded thereon, one being a single frequency, constant amplitude signal, the other alternating between a zero amplitude null signal and a constant amplitude signal of a second frequency. A servo element in the tape head senses and combines the signals from both of the tracks. A detector outputs the peak-to-peak amplitude values of the combined signal and two register modules detect and store the maximum and minimum peak-to-peak values over a predetermined period of time. These maximum and minimum values are provided to a signal processor which determines their ratio.

Abstract: A helical scan type digital recording/reproducing apparatus arranged such that data corresponding to m fields/frames are divisionally recorded in n tracks on a magnetic tape and a slow, still or frame advance reproduction mode is effected in response to an instruction from an external input. The apparatus is equipped with a signal processing circuit coupled to a rotary head for inputting data reproduced from the magnetic tape by the rotary head to store the reproduced data in a memory. In response to the instruction for the slow, still or frame advance reproduction mode, the signal processing circuit outputs a control signal when the data corresponding to one or more frames/fields are stored in the memory. Also included is a servo circuit coupled through a signal line to the signal processing circuit to be responsive to the control signal from the signal processing circuit. The servo circuit controls a capstan motor in accordance with the control signal and the reproduction mode instruction.

Abstract: A disk head position control system having a disk head controller that moves a disk head relative to a surface of a magnetic media disk encoded with a plurality of tracks of a quadrature burst pattern includes a burst pattern that comprises an asynchronous, multi-frequency track address code having burst pattern transitions that extend across the width of a track and are arranged in staggered fashion in alternate tracks such that no transitions between adjacent tracks are aligned in the disk radial direction.

Abstract: A recording/reproducing apparatus for a disc accommodates a magnetic disc in a disc cartridge. The disc may be loaded on a disc table of a disc rotating-driving device by the operation of introducing the disc cartridge into a cartridge holder which is supported for vertical movement along the rotational axis of the disc rotating-driving device. The magnetic head is brought into contact with the magnetic disc after loading the magnetic disc on the disc table and rotationally driving the disc rotating-driving device. Since the magnetic head is contacted with the magnetic disc after loading the disc on the disc table and setting the disc into rotation, the magnetic head and the magnetic disc may be contacted with each other after removal of dust and dirt occasionally affixed on the disc surface.

Abstract: An information data recording/reproducing apparatus where input information data is divided into sectors and distributed to be recorded on a magnetic tape by a plurality of magnetic heads. In a recording mode, the sector phase of the information data to be recorded is identified by input sync data which represents the phase relation thereto. In a playback mode, the sync data which identifies the sector phase of the recorded information data is obtained form the magnetic tape and used to control the playback operation. The phase relation of the information data can be restored exactly.

Abstract: A rotary scanning-type magnetic recording and reproduction apparatus comprises a plurality of magnetic heads installed on a rotary drum, and being in contact with a magnetic tape running on the peripheral surface of the rotary drum, for recording the information signal onto the magnetic tape and/or reproducing the information signal from the magnetic tape, a plurality of recording circuits connected to the magnetic heads respectively, for processing the information signal to be recorded on the magnetic tape transferred from outside the rotary drum and output it to the magnetic head, a rotary transformer for transferring the information signal sent from outside the rotary drum to the recording circuits, and a control circuit for sequentially selectively bringing the recording circuits into an active state according to the rotational position of the rotary drum, and bringing the recording circuits into an active state only during a period of time when the information signal is detected.

Abstract: A tape recorder is disclosed in which an accurate cue & review operation is possible without being influenced by the wound state of a magnetic tape or the fluctuation of the mechanical load.

Abstract: This invention relates to a magnetic recording head assembly and method enabling an end user to record a unique servo control track on a magnetic recording tape while the tape is in the recorder to be used for recording and playback of computer data. Previously, most such control tracks were applied only at the time of manufacture of preformatted media. The head assembly includes, in addition to a plurality of sets of read/write transducers, a servo write head having an extended transverse width for uniformly recording a servo signal across the width of a servo track section, and a servo erase head having a plurality of alternating erasing and non-erasing sections adapted to controllably erase portions of the previously recorded servo signal, resulting in unique servo control tracks.

Abstract: A method for following data tracks on data surfaces of a disc drive by organizing the data tracks in concentric cylinders including servo tracks on a dedicated servo surface and following servo tracks with a servo transducer that is offset from the servo track to align selected data transducers with the data tracks. To measure the offset for each data surface, a calibration correction track is written to one data surface while a track on the servo surface is followed and the correction track is read by a thermal calibration circuit while following the servo track with an offset to obtain a calibration correction indicative of electronic offsets in the thermal calibration circuit.