Abstract: Apparatus for a rotary magnetic recording medium includes a magnetic head for sensing signals from tracks which are formed on a rotary magnetic recording medium in such a manner that the front end of a recording operation continues positionally equal to the last end thereof; a head move device for movably supporting the magnetic head; a control unit for controlling the head move device to move the magnetic head onto a desired one of the tracks so as to perform a tracking operation, and a first detect device for detecting an envelope of signals obtained by the magnetic head.

Abstract: An apparatus for reproducing a magnetically recorded video signal utilizes reproduced pilot signals not only for tracking control but also for detection of the recording mode of a signal being reproduced. More specifically, the above described video signal reproducing apparatus examines for a prescribed period a fundamental cycle of a comparing signal generated by reproduced pilot signals and reference signals mixed in the reproduced pilot signals so that the recording mode can be determined based on the number of times in which the fundamental cycle is repeated in the prescribed period. For the above described purposes, a pulse output corresponding to the fundamental cycle of a tracking signal is provided by using a level detecting circuit (30) , a first differentiating circuit (31), a first frequency dividing circuit ( 33), a second differentiating circuit (34) and a flip-flop (32).

Abstract: A floppy disk driver intended to protect the disk center hole from damage when the disk is mounted. The arrangement includes a speed detection circuit for detecting a relatively low rotational speed of the disk and a control circuit for speeding up the disk to a higher rotational speed for the read/write operation in response to the detection of the lower disk speed, whereby the disk is protected from damage by being rotated at the lower speed when its center hole is held between the collet and spindle.

Abstract: An apparatus and method wherein a switching means, which has the capability of generating one of a number of different output selection signals, is set to an automatic mode or a non-automatic mode. In the automatic mode, the switching means automatically switches from generating one selection signal to another selection signal in response to a predetermined input which includes a control pulse. In the non-automatic mode, no such switching occurs. In addition, the apparatus generates a pseudo-control signal which, in the non-automatic mode only, changes in a predetermined manner in response to the control pulse so as to simulate the control pulse. According to a preferred embodiment, the above functions are performed by a switchover circuit which is employed in a multi-tape well logging system to automatically switch from one tape to another tape upon reaching an end of tape.

Abstract: In the helical scan type magnetic recording and reproducing apparatus having the tape loading mechanism for training the magnetic tape against the wall of the tape guide drum including the magnetic head over the predetermined angle, an idler is arranged to selectively engage the supply reel pedestal and the takeup reel pedestal and is provided with a driving torque transmitting means for transmitting driving torque from a drive source to this idler wherein the aforesaid driving torque transmitting means is arranged to be switchable between a 1st mode where the driving torque of the drive source is directly transmitted to the idler and a 2nd mode where the driving torque of the drive source is transmitted through a slip torque transmission portion to the idler, and this switching is effected in relation to operation of the aforesaid tape loading mechanism.

Abstract: An auto-reverse tape recording and reproducing apparatus has a mode setting means for holding a tape running direction in normal mode or reverse mode, and this mode setting means is returned to the normal mode position in connection with the return movement of an operating means for playing, only when the mode setting is in the reverse mode position, and further this mode setting means is not displaced in connection with the forward movement of a mode change-over means when a base plate of a magnetic head is in the returned position, but is displaced in connection with the forward movement of the mode change-over means when the base plate of the head is in the forward position.

Abstract: A disk for use in a dedicated surface track following servo system has a plurality of radially spaced circumferential tracks on which synchronizing, position, and track region identifying transition pairs are recorded together with guard transition pairs between the synchronizing and position transitions pairs and between the position and track region identifying transition pairs. The guard and position transition pairs each bridge two adjacent tracks and are separated radially and circumferentially from track to track in repetitive staircase fashion.

Abstract: A cover for the light channel for a device for switching-off at the end of its run a magnetic cassette tape with a transparent leader tape, an opening being provided in the bottom part of the cassette for accommodating the light, the opening being defined by a one- or two-part light shaft having slotted light channels for the passage of the beams of light towards the light-receiving elements on the side of the device, the light shaft 5 located only in the bottom part of the cassette being provided with an encircling ledge 8 below the light channels, 6, 7 on which ledge a flexible piece of film 9 rests which is transparent at least in the region of the light channels, or the light shaft, which is divided in the middle and fills out the height of the interior of the cassette housing, has an encircling ledge 8, 10 in each of the top and bottom parts 5, 5 a thereof, outside the region of the light channels, between which a flexible transparent piece of film 12 covering the light channels rests, the piece of film

Abstract: A video signal reproducing apparatus which reproduces a video signal from many evenly spaced recording tracks formed on a recording medium, comprises:a first rotating head;a second rotating head which has a larger width than the first rotating head and which traces the recording tracks alternately with the first rotating head;detecting apparatus for detecting the positional errors of the first and second rotating heads relative to one of the recording tracks by using the outputs of these heads;adjusting apparatus for adjusting, on the basis of the difference in head width between the first and second rotating heads, the output of the detecting apparatus related to the second rotating head;recording medium moving apparatus for moving the recording medium in a direction which intersects the recording tracks; andcontrol apparatus for controlling the moving apparatus on the basis of the output of the detecting means adjusted by the adjusting apparatus.

Abstract: A floppy disk drive apparatus includes a control signal generating circuit for generating a step signal and a direction instruction signal, head driving section for driving a magnetic head in the radial direction of a floppy disk, and a detector circuit for generating an output signal when the magnetic head locates in the outer limit location of the floppy disk. The detector circuit is inhibited from generating an output signal in response to the direction instruction signal generated for driving the magnetic head in an inner direction of the floppy disk.

Abstract: An improved servo control system for data track following of the read/write head in a magnetic recording system uses a pattern of segments of servo information slanted across the data tracks. The time of flight of the servo segment from occurrence of a reference pulse until the peak servo signal is read by the head is an indication of the position of the head in a direction perpendicular to the desired track. This time is compared with the known time of flight if the head were precisely over the centerline of the desired track and the time difference is used to generate a control signal to position the head over the track centerline. In an embodiment where each segment is slanted across only one track, the reference pulse is the beginning of the servo signal and the time measurement is the number of fixed frequency magnetic transitions read by the head in the servo segment.

Abstract: A helical-scan recorder for two-channel digital video recording comprises two pairs of write-read heads which are situated diametrically opposite each other. To simplify tracking it is proposed to record tracking, signals of different frequencies with one head of each of said pairs of heads and to read said tracking signals during recording via crosstalk, each time using the other head of each of said pairs of heads.

Abstract: The performance of a track-following servo system for a disk file is improved by the feeding forward of a prediction of track eccentricity into the normal feedback control loop. The eccentricity related function is derived by combining functions of the position error signal and of the input signal to the head position actuator during at least one revolution of the disk. The eccentricity function is stored and then fed forward to the actuator during a subsequent revolution of the disk. The eccentricity function may be a track shape position signal formed from the difference of the PES and the double time integral of the actuator current. Alternatively it may be an actuator current profile formed from the difference between the actual current and the double time derivative of the PES.

Abstract: The disclosed information reproducing apparatus includes a transporting portion for moving a tape-shaped recording medium at one of at least two different speeds, a reproducing head for reproducing the information on the recording medium as it is moved by the transporting portion, and a detecting portion for detecting whether or not the speed of movement of the recording medium during reproduction is coincident with that of the recording medium during recording of the information.

Abstract: A recording and/or reproducing head which is adapted for recording signals on a recording medium and/or reproducing the signals from the medium when the head and the medium are relatively moved at a first relative speed is cleaned with a head cleaning member when the head and the cleaning member are relatively moved at a second relative speed lower than said first relative speed.

Abstract: A storage file for particular use with a flexible magnetic disk having a series of concentric magnetic tracks thereon, comprising a four phase stepping motor for moving a transducer head radially of the magnetic disk. The stepping motor has several sets of first, second, third and fourth phase windings arranged sequentially in the order named. A radial drive control circuit is provided which normally acts to cause energization of the stepping motor windings in a single phase drive mode to cause rotation of the rotor by discrete increments. In order to prevent the rotor from being trapped in alignment with the third phase windings, instead of being returned to the first phase windings, when the disk file is electrically turned on, the radial drive control circuit further functions to briefly energize a selected one or more of the second, third and fourth phase windings of each set, with the simultaneous or subsequent energization of the first phase windings.

Abstract: In a rotary head type digital information signal recording and reproducing apparatus having plural rotary heads mounted on a rotary drum so as to be capable of recording and reproducing signals on parallel, oblique tracks on a magnetic tape, a tracking signal is recorded on at least one portion of each track which is not overlapped with a portion of each track where a digital information signal is recorded to avoid interference between the tracking signal and information signal. The tape travel speed and the rotary drum rotation speed are changed depending upon the transmission rate for a digital information signal to be recorded and reproduced to make the wavelength of a recorded signal frequency constant irrespective of the signal transmission rate. Tracking control is enhanced without increasing the error rate.

Abstract: A magnetic data storage apparatus such as a Winchester disk drive is disclosed wherein a transducer head or heads are normally held in contact with a magnetic disk or disks and move out of contact therewith for data transfer when the disk or disks are set into rotation. In order to preclude the possibility of the transducer head destroying the series of concentric data storage tracks on the magnetic disk, the head is normally retained on a head landing track formed on the disk, preferably radially inwardly of the data storage tracks. When the disk is set into rotation, the head is transported to a position over a desired one of the data storage tracks for the commencement of data transfer only after it has moved out of contact with the head landing track. Upon completion of each run of data transfer, the head is returned to a position over the head landing track for landing thereon when the disk is set out of rotation.

Abstract: Apparatus for playing back from recording media (such as magnetic tape) recorded information which includes both preselected segments and unpreselected segments, such as edited video scenes (burst and still) and unedited video scenes. The apparatus includes a memory for storing start and end addresses (which may be the same) of preselected segments recorded on the media, and a device for designating an unpreselected segment for playback such as on a display monitor. The apparatus includes control logic (1) for determining from the stored start and end addresses of preselected segments the start and end addresses of a designated unpreselected segment, and (2) for causing playback of the designated segment.

Abstract: The track access time in a disk drive system is minimized by determining an optimum velocity profile each time the system is operated. The optimum velocity profile is determined by performing repeated seek operations with successively higher velocity profiles until a seek failure occurs. A velocity profile slightly lower than the profile which caused failure is then used to control seek operations. During seek operations, the time between track crossings is monitored and the velocity profile reduced if the transducer of the disk drive system is not adequately following the preset velocity profile.