Abstract: Provision is made of a traverse cycle measuring circuit for measuring the traverse cycle based on a signal CNIN obtained by digitalizing the tracking error signal at the time of a track traverse, a register in which any target value of the traverse cycle can be set, a circuit for comparing the measured traverse cycle and set target value, control circuits, for controlling the tracking and sled so that the detected speed of traverse converges to a target value, and counting circuits for counting the number of traversed tracks based on the signal CNIN, the target value of the register being reset to a value by which the speed of traverse is reduced when the count of the counting circuit reaches a number of tracks (N-.alpha.) smaller than the target number of tracks by exactly .alpha..

Abstract: In a magnetic reproduction system in which a magnetic tape must be controlled to run so as to keep a specified relative phase to a rotary phase of a rotary head, a tracking control apparatus obtains a characteristic curve showing a characteristic relationship between the relative phase and an envelope level of a reproduced information signal obtained by the rotary head by changing the relative phase, obtains a regression curve with respect to the characteristic curve, and controls the magnetic tape to run so that the relative phase becomes a value corresponding to a maximum value point of the regression curve.

Abstract: A magnetic tape drive system (20) records a directory block (CL) at a predetermined position on tape (22), and preferably at the beginning of tape. The directory includes, for each recorded track on tape (22), a data block number of the data block recorded at an end of the track. Preferably a plurality of copies of directory block (CL) are recorded, preferably in reverse direction. Upon receipt of a command to locate a target data block recorded on tape (22), a processor (102) directs a transport controller (82) to position a read element (30R) at the predetermined position on tape (22) for reading the directory. The read element reads the directory from tape (22).

Abstract: A digital video tape recording method for trick play includes the steps of dividing the data area of a video sector of respective tracks of the digital video tape into first, second and third regions, interspersely recording normal play data and trick play data in the first and third regions, and recording the normal play data in the second region, wherein the trick play data recorded in the first and third regions is frame data corresponding to the maximum odd-fold speed of a plurality of given odd-fold speeds, and the same trick play data is repeatedly recorded for a number of tracks equal to twice the number of the maximum odd-fold speed, thereby enabling satisfactory trick play at various odd-fold speeds and with various scanners.

Abstract: A preamplifier circuit arrangement for a magnetic or magneto resistive transducer, such as a record/replay head, in which a cascode preamplifier stage, and a stage providing a floating reference voltage for a following amplifier, are linked by an emitter coupled pair of transistors, one in each stage, such that the d.c. currents in the two stages flow in common through the transducer.

Abstract: The lubricant film for a near contact magnetic recording device is maintained by a closed loop servo control for a recirculating lubricant supply system. A reservoir closely overlies the disk data surface and includes a heater for controlling the temperature difference between the reservoir and the disk surface. Decreasing the heater current reduces the film thickness and increasing the heater current increases the film thickness. A wick system gathers lubricant from within the disk enclosure, which may have been spun off the disk or condensed from the lubricant laden atmosphere and returns the lubricant by capillary action to the reservoir. Further, the reservoir includes two portions which are independently controllable. The first overlies the data band of the disk and the second overlies the start/stop zone and the head when the latter is not operational and parked at the nonoperating location.

Abstract: An adaptive equalizer includes a recording density detector for calculating a recording density reference value by obtaining the track radius using input track information, a reference tap coefficient storage portion for storing the reference tap coefficient obtained according to the channel impulse response at the lowest density position, a tap coefficient controller for obtaining a tap coefficient according to the recording density using the recording density reference value on the basis of the reference tap coefficient stored in the reference tap coefficient storage portion, and a waveform equalizer for eliminating the interference of the signal adjacent to the input reproducing digital signal using the tap coefficient obtained from the tap coefficient controller, to output the reproducing information signal.

Abstract: A signal read out from a disk by a pickup is written in a RAM. The signal written in the RAM is read out at a speed lower than the writing speed to perform a reproduction operation. When there is an abnormality of the servo, the writing to the RAM is stopped and the servo is returned to a predetermined operation point to perform a re-try. After the occurrence of the abnormality of the servo, whether a return data and a data on a position just in front of a position where the servo abnormality occurs coincide with each other or not is determined. When the data coincide with each other, data on the position where the abnormality occurs and positions subsequent thereto are written in the RAM. When the data do not coincide with each other, the servo repeats the re-try for a predetermined period of time.

Abstract: A method for defining and writing parallel and concentric magnetic signal tracks to a spinning disk surface of a magnetic data storage disk drive system using the components of the Head Disk Assembly (HDA) implemented by an appropriately programmed digital signal central processing unit (CPU) or micro code in an integrated circuit (IC) and a digital signal random access memory RAM is described wherein an initial magnetic signal track is written under least (minimum) energy equilibrium conditions with undulating boundaries and a meandering center line relative to axes of the spinning disk surface for one revolution of the surface. Then servoing to an edge of the just written track, a digitized position signal table is created in memory for storing digital position signals representing the amplitude of the signals read from n sampling points per disk revolution over a number of disk revolutions, where n is determined with reference to `Nyquist criteria`.

Abstract: A method for synchronously operating two or more rotary head digital audio tape recorders without having to dedicate a separate timing track. The present invention synchronizes the machines in three steps. First, the slave unit reads the time code value from the data stream and compares this time code to the master's time code, examining the difference in time code values and adjusting the transport speed so that the values are approximately equal. Next, the slave's capstan motors are slowed down (or sped up) so that the slave and master units are within one drum revolution of each other. Finally, the slave's microprocessor adjusts the speed of the entire system to skip individual samples until the master and slave units are synchronized.

Abstract: The invention is generally directed to a device which receives control signals and is selectively capable of serially controlling an auxiliary device. According to one aspect of the invention, the controlling device is operable in a first mode where control signals are used to control the device itself, in a second mode where the device uses the control signals to serially control the auxiliary device and in a third mode where the control signals are used to control both the device and the auxiliary device. According to one aspect of the invention, the device may be a multi-track recorder and the auxiliary device may be a video tape recorder.

Abstract: A floppy disk controller enters into a standby mode to reduce electric power consumption, and includes a standby controller which causes a floppy disk driver unit to report a status change to a recovery controller during the standby mode to recover the floppy disk controller to an active mode, thereby indicating the correct status of the floppy disk driver unit at all times.

Abstract: When a magnetic track is formed, the magnetic track is divided into a plurality of track areas in its longitudinal direction. Information signals are recorded in the divided track areas independently of each other. At a portion of the magnetic track, there is provided a reference track area in which a specific reference signal is recorded. When an information signal is recorded in either of the track areas, the reference signal is played back from the reference track area, and the information signal is recorded in the track area corresponding to the information signal using the played back reference signal as a reference for timing of the recording.With the described arrangement, when a plurality of information signals are recorded in a plurality of track areas, which are formed by dividing a track in its longitudinal direction, independently of each other, a signal recorded in a track area is prevented from adversely affecting another signal recorded in a neighboring track area.

Abstract: A method for increasing data storage on a hard disk drive is disclosed herein, the method including determining a capacity goal for the disk drive, partitioning the usable disk surface on the disk drive into regions, and calculating a transfer rate based on the capacity goal and the usable disk space. The rate at which data may be transferred is then increased by a first selected quantity and/or decreased by a second selected quantity to establish a higher and/or lower transfer rate. For multiple data heads used in an individual disk drive unit, a first group of heads is partitioned from the remaining heads based on a particular selection criteria, and the remaining heads are arranged into a second group. The first group of data heads then operates at a higher transfer rate than the second group of data heads, and an algorithm for reading and writing data at the different rates is created.

Abstract: A diskette comprising a jacket, a liner material disposed within said jacket, a flat circular media having a magnetic coating on both sides disposed within said liner material, a hub attached at the center of said media, a plurality of servo grooves on at least one of said sides of said media that have stitched patterns that will alternate on-and-off at twenty kilohertz in the presence of a constant, unmodulated light source. The diskette is magnetically formatted with reference and data tracks recorded in such a way that extremely accurate position determinations can be made by looking at the analog amplitude of the detected tracks and comparing them at different head positions.

Abstract: A magnetic reading and/or recording apparatus for reading and/or recording information from/on a magnetic information track on a web comprises a magnetic reading and/or recording element and a flexible member for supporting the magnetic reading and/or recording element for rotation about an axis perpendicular to a longitudinal axis of the web while restraining the magnetic reading and/or recording element from rotating about an axis parallel to the longitudinal axis of the web and an axis in a direction transverse to the longitudinal axis of the web.

Abstract: A helical scan system (10) determines whether a medium is a non-native formatted medium and controls operating parameters (e.g., tape speed) so that a non-native formatted medium can be read without resort to embedded servo information in the non-native medium. The helical scan system reads the medium in a manner to obtain format-indicative information therefrom, and then determines whether the medium is non-native formatted. If the medium is non-native formatted, a controller determines operating parameters required by the system to read the non-native formatted medium and generates signals corresponding to the required operating parameters. The medium is preferably read in a slow speed mode in order to obtain format-indicative information therefrom, and block header information obtained from the medium is analyzed to determine whether the medium is non-native formatted.

Abstract: The invention is a write clock generator circuit adapted for use in disk drives having either dedicated servo or sector servo architecture. A high frequency write clock signal is generated from a relatively low frequency reference signal synchronized to disk rotation. The reference signal may originate from a number of sources, including a dedicated servo pattern, a sector servo pattern, any index pattern, or a spindle pulse. A clock generates a clock signal having a predetermined number of cycles for each reference period. A counter coupled to the output of the clock counts the number of clock cycles generated for each reference period. The number of cycles is then compared to an expected number corresponding to a desired clock frequency. If the compared numbers are not the same, an error signal is generated. Control logic receives the error signal and the reference signal, and generates an appropriate control signal.

Abstract: A tracking apparatus for a sampled servo system, wherein a tracking servo loop is opened when a jump command is generated by ceasing to supply a tracking error signal to a tracking control circuit, which is instead supplied with a kick pulse to start a track jump operation. Thereafter the tracking control circuit is reset to relay the tracking error signal when a read track is switched causing a change in value of an odd/even determining signal to close the tracking servo loop. Finally a brake pulse is supplied to the tracking control circuit for terminating the track jump operation. This enables an irradiating spot to be stably led into a target track when the track jump operation is switched back to the tracking servo operation even if the track pitch of the disk being read is variable.

Abstract: A digital tape recorder is provided in which main digital signals and time code signals are recorded on a magnetic tape after realization of the timing concurrence between these signals. To this end, a delay correction circuit 23 for delaying the input time code signals by a delay time at an A/D converter 13 or a delay time at a digital input interfacing circuit 16 are provided. The input time code signals delayed by the delay correction circuit 23 and main digital signals from the A/D converter 13 or the digital input interfacing circuit 16 are transmitted to an encoder 17 and recorded on the tape 30 in such a state in which the in-line relationship or timing concurrence is maintained between these main digital signals and the time code signals.