Abstract: Fuzzy control is disclosed in the environment of tracking control for a playback head relative to a medium from which signals are played back. Tracking control data is generated as a function of the detected signal level of the played back signal by using fuzzy inference to obtain direction and magnitude values of the control data which then is used to adjust the tracking of the head.

Abstract: A magnetic recording method and apparatus which performs a quadrature phase shift keying operation on a digital information signal, superimposes a high frequency bias signal on the performed signal, records the resulting signal into a deep portion of a magnetic layer of a magnetic tape with a first rotational head, and records a video signal in a surface portion of the magnetic layer above a track formed by the former recording, with a second rotational head which is different in azimuth angle from the first rotational head, the frequency of the high frequency bias signal being set to a value which is about four times as high as the carrier frequency of the quadrature phase shift keyed digital information signal, thereby eliminating a 5th-order distortion component due to cross modulation of the high frequency bias signal and the carrier frequency.

Abstract: A generally rectangular outer housing is sized to fit within the full height five and one quarter inch form factor. A drawer is mounted for sliding motion within the housing along a longitudinal axis thereof from a retracted position in which the drawer is substantially fully contained within the housing to an extended position in which a forward portion of the drawer extends beyond a forward transverse end of the housing. A DAT tape drive is mounted within a rear portion of the drawer and has a forwardly opening cassette insertion slot. A cassette magazine is provided that has a plurality of vertically spaced receptacles for holding a plurality of DAT cassettes in a vertically stacked configuration. A magazine loader is mounted in the forward portion of the drawer for receiving and vertically reciprocating the cassette magazine and for selectively transferring cassettes between the magazine and the cassette insertion slot of the DAT tape drive.

Abstract: A magnetic tape drive simultaneously senses on a magnetic tape three evenly spaced-apart servo track areas for servoing a multi-track magnetic head to follow a concurrent set of data tracks on the magnetic tape. The data tracks are arranged into a plurality of track groups. Each track group has a first and second subgroup of data tracks. The first subgroup of tracks are scanned in a first relative motion of the magnetic tape and magnetic head as a forward direction (tape is being spooled from a supply tape reel). The second subgroup of tracks are scanned in a second relative motion of the magnetic tape and magnetic head that is opposite in direction to the first relative direction and is a forward direction of scanning. While writing data in any one of the plural track groups, a servo dropout affecting most of the servo track areas is detected and indicated as a servo error. Writing is aborted. The relative position of the magnetic tape and head is detected at both longitudinal ends of the servo dropout.

Abstract: A video signal processing system for a double deck VTR which can accomplish the simultaneous recording/playing function in both video decks and the dubbing function between two types of video tapes, wherein input/output select switches and input/output analog switches are located for appropriately processing the video signal between the respective devices of the double deck VTR.

Abstract: A video processing system comprises a processing unit, a VDU, and a look-up table. A user defined profile is displayable on the VDU and can be adjusted interactively by way of a stylus and touch tablet. Data representing the profile is stored in the look-up table. An input video clip is stored in digital form in a disc store and output video clip frames are generated in accordance with the user defined profile data. The system can be used for example to stretch or compress a video clip in time.

Abstract: A head position recognition method, a speed calculation method, and a head movement speed control device which provide for an overall improvement in storage device performance without increasing the seek time of the data head. Discrete servo sectors are provided circumferentially to the recording medium, four servo patterns with a minimum repeat cycle of 24 tracks are written into each servo sector. The range of the head seek distance that should be obtained at the current servo sector is estimated based on the previously calculated head seek distance, and the calculated head seek speed is corrected to the true head seek distance.

Abstract: A test disk is used to measure disk drive alignment and other parameters without removing the drive from its computer system and without any need for special test equipment. It includes a pair of prerecorded signal tracks separated by a gap smaller than the width of the head so that one track is used for providing computer readable signals and the other is used to inject variable interference into the composite signal under the head. Multiple pairs of tracks at differing radii are included for measuring drive alignment and other parameters. The method for measuring alignment and other parameters suppresses measurement errors due to disk signal modulation and changes in track radius. Alignment testing requires only a single measurement and is capable of resolving the measurement to the nearest bit so that maximum accuracy is achieved.

Abstract: In a magnetic disk drive device comprises a magnetic disk having a plurality of concentric tracks on a data surface on which data are recorded. At least one of the tracks serves as a shipping area. Dedicated data is written in each of the data sectors in the shipping area and a DC erase section is formed in one of the data sectors in the shipping area. The dedicated data and the DC erase section are detected at the time of starting the rotation of the magnetic disk, and the speed of the disk is measured on the basis of the data thus obtained. The speed as obtained from the above data is monitored to determined when it has reached a predetermined value.

Abstract: The present invention relates to a double-deck VTR which can reproduce continuously, without any interruption, contents of the same program tele-recorded on a multitude of tapes. The present invention further relates to a continuous reproduction method of tapes for a double-deck VTR wherein naturally-matched video images can be viewed, during the reproduction by the double-deck VTR, according to detection of auto marking, end marking and start marking signals. The reproduction of tape tele-recorded with the next contents is readily performed simultaneously with the ending of the tape being reproduced in accordance with auto marking, end marking and start marking signals marked on a multitude of tapes separately tele-recorded with the same program.

Abstract: A magnetic reproducing device such as a VTR, DAT, or the like reproduces recorded information from inclined tracks on a magnetic tape, having auxiliary information, such as address information, recorded in areas in the inclined tracks, includes a rotary magnetic head rotatable for successively scanning the tracks on the magnetic tape to generate a reproduced signal representative of the auxiliary information. A pulse signal is generated having pulses in synchronism with each rotation of the rotary magnetic head through a predetermined angle. Window pulses used subsequently to extract the auxiliary information in the areas from the reproduced signal are generated based on the pulse signal.

Abstract: Apparatus for fine positioning a tape head relative to a head carriage that is coarsely positionable by a lead screw. The fine positioning apparatus includes parallel first and second resilient support beams oriented generally parallel to the direction of tape travel and having their ends fixedly secured to the head carriage so as to be deflectable in a direction transverse to the direction of tape travel. The centers of the parallel first and second support beams have their centers secured to a tape head frame which contains the tape. A linear motor drives the tape head frame against the resilience of the first and second resilient support beams in response to a drive signal which, for example, is derived from tracking error information produced pursuant to reading of servo information on tape. Pursuant to the displacement of the tape head frame against the resilience of the support beams, the magnetic tape head is moved along a linear path transverse to the tape travel direction.

Abstract: In a disk apparatus of contact-start-stop system, a head slider carries out a contact-start-stop operation at a non-specified position taken in the radial direction of a disk-shaped recording medium. This can be achieved by entering a random signal from a random number generator to a means for positioning the head slider in the radial direction of the disk when the recording medium begins to stop rotating. Accordingly, the head slider can be effectively inhibited from adhering to the disk, and the disk becomes unlikely to suffer wear, damage and head crash, and further, many information tracks can be formed on the disk.

Abstract: A computer memory backup device which utilizes standardized computer tape cartridges is disclosed. The focus of the invention is upon the techniques for ascertaining the appropriate placement of such cartridges to allow operation of the computer memory backup device. The device being connected to a computer allows for the determination of a cartridge presence through the use of an optical sensor mechanism. The sensor mechanism includes a light emitting diode (l.e.d.), light pipe and phototransistor. During any time that the cartridge is not in the computer memory device or improperly or incompletely inserted the electromagnetic radiation emitted by the l.e.d. will be directed by the light pipe to the phototransistor. In this manner a negative determination is correctly made. When the cartridge is correctly and completely inserted, the pathway of the electromagnetic radiation is blocked between the light pipe and the phototransistor. In this manner a positive determination is correctly made.

Abstract: A method of and apparatus for accurately positioning a magnetic read head in relation to a magnetic data track recorded in a magnetic recording medium of a photographic filmstrip. The read head is precisely aligned with one edge of the moving filmstrip through the use of an optical detector and an optical pattern placed below the filmstrip and extending beyond one edge of the filmstrip. The portion of the optical detector field of view corresponding to the optical pattern and the portion corresponding to the filmstrip are detected and the detected signal is processed to provide a control signal for moving the read head with respect to the film edge so as to position the head a precise distance away from the edge of the filmstrip without requiring physical contact with the filmstrip edge.