Abstract: A flexible disk unit having a reduced thickness includes a spindle motor for rotating a magnetic recording medium having a magnet at its outer periphery, a movable carriage supporting a magnetic head and a stator surrounding the spindle motor and including a coil opposed to the magnet. The stator has a recess which is adapted to surround the tip of the movable carriage when the carriage is moved towards the magnetic recording medium. A head shield portion is disposed between the stator and the magnetic for shielding leakage flux in the direction of the magnetic head.

Abstract: A disk device with a cleaning device and a cleaning method according to the present invention include cleaning motor control means for rotating a disk oppositely to a direction of rotation of the disk in recording and regeneration, and seeking means for forcing a slider to seek the disk over a whole recording region during the opposite rotation of the disk to permit any dust to adhere to the slider, whereby a motor is started and stopped (contract-start-stop) after cleaning the recording region, so as to force the dust adhering to the slider to fall on a disk surface for cleaning the slider.

Abstract: A computer-based system, such as a value printing system, has a host data processor having at least one disk drive that includes a first read/write head for reading data from and for writing data to a removable data recording disk. The system further includes a printer, coupled to the host data processor and responsive thereto, for printing indicia indicative of a monetary value. The system further includes a removable data recording disk having an integral data processor including a memory for storing data expressive of a monetary value associated with printed indicia. The integral data processor further includes a second read/write head coupled to the recording medium for communicating with the host data processor through the first read/write head.

Abstract: A portable audio unit has a main unit, such as a CD player or tape recorder. The main unit is connected to a control unit by a cable. Audio and control signals are transmitted by the cable. The control unit has a connector for an earphone. Audio signals are transmitted by the cable from the main unit, to the control unit and to a connected earphone. Control signals are transmitted from the control unit to the main unit for controlling functions such as volume, power, tape-play, etc. The main unit has a built-in winder that stores and retrieves the cable. The control unit may be attached to the main unit when the cord is wound up and stored. With the control unit attached and the cable stored in side the main unit, the portable audio unit may still be operated by the control unit which forms a built-in control panel. With the cable extended, the control unit may be used as a remote control permitting the main unit to be placed in a handbag or pocket.

Abstract: A device for locking up a video cassette recorder having a box with a base, a top wall and upstanding side walls, and with intermediate walls therebetween, a drum journaled through the front and rear walls at the center of the box, the drum having a centrally located diametric bore, a pair of locking rods independently supported for axial movement through apertures of an end wall and an adjacent intermediate wall, the movement being between an operative position spaced from the shaft and an inoperative position within the bore of the drum, a dial for rotating the drum extending to the exterior of the front wall, and handles to axially reciprocate each rod extending through slots in the front wall laterally offset from the drum.

Abstract: An apparatus (and a method for producing the same) for preventing internal vibrations produced as a result of rotary motion at a predetermined frequency within a device mounted in an enclosure from being translated into resulting rotary motion of the device comprises n vibration isolation mounts located between the device and the enclosure, said vibration isolation mounts having stiffness characteristics and being positioned so that rotational motion of the device at the frequency of the rotary motion is eliminated. The vibration isolation mounts are arranged and configured so that when the rotary motion produces linear and rotational forces, the net moment of all forces about the center of gravity of the device is equal to zero. The vibration isolation mounts may be isotropic. The isolation mounts may have different stiffness's. Three or more mounts may be used. Alternatively, the vibration isolation mounts may have the same stiffness's but their positions may be varied.

Abstract: A service cassette for simulating the presence of a conventional video tape cassette within a conventional video cassette recorder, player and camera wherein a retractable extending arm is provided for actuating a sensor that detects the presence and absence of an opaque magnetic video tape wherein the sensor is mounted beyond the frame structure of the service cassette within the video equipment. An extending arm is slidably connected to an end wall of at least one of the end members of a c-shaped frame structure of the service cassette. The slidable connection allows the extending arm to move between a retracted position and an extended position. When in the retracted position, the extending arm does not extend beyond the frame structure of the service cassette and does not actuate the sensor mounted beyond the frame structure of the service cassette within the video equipment.

Abstract: An apparatus and a method for mode changing of a deck mechanism suitable for used in a compact cassette tape recorder. The apparatus includes actuating members for selectively actuating a mode switch, first restriction members for restricting rotation of the actuating members, selection members for selectively transmitting drive power in order to carry out a mode of the deck mechanism, biasing members for causing a cam assembly to initially engage with power transmission members, and second restriction members for restricting rotation of the selection members. The preferred apparatus employs a single cam gear and a single electrically operated solenoid for the mode changing operation of the cassette tape recorder and does not cause over-running of the tape out of the tape cassette in a mode changing operation.

Abstract: A system for heating a tape drive includes a heating element which is actuated by the same voltage that drives the motor. An electronic switch is responsive to the motor voltage and turns the heating element on when the motor is not running and off when the motor is running.

Abstract: A portable recording and reproducing apparatus is adapted to reproduce a melody recorded on a recording medium such as a magnetic tape and to amplify the melody and voice through a speaker as the voice is inputted from a voice input unit in tune with the melody. The apparatus is formed integrally by incorporating a sound recording medium accommodating portion, the voice input unit, and the speaker via a grip portion, and excels in portability.

Abstract: A method for correctly measuring the time remaining for a tape running in a tape recorder on the basis of a previously calculated remaining time even when the speed of the tape running in the tape recorder changes or runs at a high speed. The method determines whether or not a present remaining time has been calculated and based on this determination other steps are performed. Other steps include determining the rotation period of a supply reel, determining whether or not the tape is running at a normal speed or whether or not the tape is running in a forward direction, whether the speed of the tape is a high speed or not, subtracting from or adding to the rotation period, a change in rotation period based on the speed and direction of the tape for every rotation of the reel to calculate a new rotation period and calculating a new remaining time by subtracting the new rotation period from or adding the new rotation period to the present remaining time determined in the first mentioned step.

Abstract: In a recording and/or reproducing apparatus (1) for a magnetic-tape cassette (6), the apparatus having at least one magnetic head (31, 32), at least one pressure device (46) for urging the cassette (6) towards the magnetic head (31, 32), a control device (52) for starting a "recording" mode, and a locking device (71) for locking the control device (52), the pressure device (46) and the locking device (71) are arranged and constructed to cooperate with one another, and the pressure device (46) holds the locking device (71) disengaged from the control device (52) when no cassette (6) has been inserted into the apparatus (1), and the pressure device (46) releases the locking device (71) to allow cooperation with the control device (52) when a cassette (6) has been inserted into the apparatus (1). (FIG.

Abstract: The invention is a protective member for the cassette receiving chamber of VCRs and audio cassette recorders. The device is insertable into the VCR and may be locked into place by means of a frictional member that engages with the flange located around the cassette access door of the VCR etc. The device prevents the insertion of foreign objects into the cassette receiving chamber of the VCR, etc.

Abstract: A tape recorder including a limiter gear mechanism having a torque limiter; a driving device for rotationally driving the limiter gear mechanism in a forward or reverse direction; a swing lever swingably provided between a pair of reel bed gears, and having a gear train adapted to be rotated by the limiter gear mechanism; a magnetic head supporting member for supporting a pair of magnetic heads selectively operable according to a tape travelling direction, one of the magnetic heads between an operative position in contact with a tape and an inoperative position in separation from the tape; a direction lever for selecting the tape travelling direction and controlling movement of the magnetic head supporting member so as to selectively restrict movement of the other magnetic head to the operative position; and a mode lever movable among a neutral position, a record position and a playback position, and biasing the magnetic head supporting member to the operative position of one of the magnetic heads when the mo

Abstract: A disc change signal generating circuit which uses an index sensor for generating an index pulse in order to detect a rotation of a floppy disk, a timer to input the output of the index sensor into a clear terminal and to input a clock signal into a clock terminal and thereby generate a value with a predetermined frequency, and a disk change signal generating circuit for generating a disk change signal by input of the output of the timer.

Abstract: A magnetic disk apparatus is disclosed wherein the apparatus comprises a magnetic disk, magnetic heads for recording and reproducing information to and from the magnetic disk, a disk driving device for driving the magnetic disk, head driving device for driving the magnetic heads, a mechanical portion driving circuit for operating the disk driving device and the head driving device, a logical operation device for exchanging signals between the magnetic heads and the mechanical portion driving circuit, a first box for containing at least the magnetic disk, the magnetic heads, the disk driving device, and the head driving device, and a second box, detachably connected to the first box, for containing at least the logical operation device, wherein signals are exchanged between the first box and the second box. The first box and the second box are electrically connected and the second box contains at least the logical operation circuit.

Abstract: A lock mechanism for disk drives includes a case slightly shorter than an ordinary diskette, a lock slantly disposed in front of the case and controlled by a key, a transmission shaft extending into the case and being moved forward when the lock is locked, and a hook member pivotally connected to the transmission shaft at the end extending into the case. The case has two spring clips separately accommodated in two recesses formed at two front corners of the case and are clamped by an upper and a lower link of a linkage which connects to and moves together with the transmission shaft. When the case has been pushed into a disk drive via a disk slot, the forward movement of the transmission shaft and the linkage allows the spring clips to spring open and push against the front inner wall of the disk slot of the disk drive. The backward movement of the transmission shaft and the linkage allows the spring clips to be pressed closed, permitting the case to be freely inserted into or drawn out of the disk drive.

Abstract: A sheet-shaped cleaner including a resilient film and nonwoven cloth consisting of synthetic fibers formed on one side of the film is disposed in opposition to a guide roller. A magnetic tape is sandwiched between the guide roller and the cleaner and with the magnetic surface of the magnetic tape being contacted by the nonwoven cloth of the cleaner. The film of the cleaner is wedged between locking portions of the cassette in order to cause the cleaner to bow in a direction away from the guide roller such that the nonwoven cloth of the cleaner is biased under a low force against the magnetic surface of the tape. Accordingly, foreign matter on the surface of the magnetic tape is removed.

Abstract: Device for cleaning a head assembly (12) of a magnetic tape player and/or recorder with a cleaning solution. The device includes a housing (14) adapted to be inserted in the player/recorder in a cleaning position, a drive mechanism (18) and wiper and (16) connected within the housing (14) for providing oscillating movement, and a cleaning head (20) connected to the wiper arm (16) for cleaning the head assembly (12). The cleaning head (20) comprises a rigid body (82) having a plurality of cleaning materials (84, 86, 88) extending forwardly out of the rigid body (82). One of the cleaning materials is a solution-holding material (84) characterized by its ability to absorb a cleaning solution, for spreading the cleaning solution on the head assembly (12). Another cleaning material (86, 88) comprising a relatively stiffer material for scrubbing the head assembly, is positioned on both sides of the solution-holding material (84).

Abstract: A switch assembly that can vary at least two controllable parameters and can vary the upper, lower and any intermediary limits of the switch assembly. The switch assembly has a pair of nested coaxial rotary knobs each attached by shafts to sensors that determine the radial position of a reference point on each knob. The knobs rotate with respect to each other and are constructed to allow rotation of the knobs with one hand. The sensors are attached to the controls of the parameters, such that rotation of the knobs varies the output of the parameters. The sensors are coupled to a magnetic clutch that engages and prevents rotation of one of the knobs, when the knob is rotated into a predetermined radial position. A computer can be connected to the magnetic clutch and sensors. The computer receives input signals from the sensors and produces an output signal to the clutch, to engage the clutch and prevent rotation of the knob in accordance with a computer program.

Abstract: A cleaning system for magnetic tape intended for high density magnetic data usage combines passing a high volume flow of negatively ionized air across a moving tape surface with simultaneous wiping of one surface of the tape with a soft, non-abrading material to remove dust and foreign particles from the tape. The air flow passes through a filter, which removes the particles. The air then passes through an ionizing grid and back across the tape in a continuous, closed loop operation. The cleaning material is housed in a removable cartridge along with the air filter. A brush moves in response to loading of the tape to pinch the tape and thus remove particles from the surface opposite the tape surface engaged by the soft material.

Abstract: A portable audio apparatus allows a user to sing along with the recorded song, the user's voice and recorded song being outputted through a speaker. The apparatus permits the recorded lyrics or recorded tune of the song to be substantially eliminated prior to being reproduced by the speaker. The apparatus can operate in a fast forward or reverse mode and will stop between adjacent songs. A power savings circuit interrupts the supply of power to a motor to stop the latter from continuing to operate on a fast forward or reverse mode.

Abstract: A method and system detect and remove particles from a tape. Debris on a tape can cause errors. Location of the tape is continuously monitored, and when an error is detected during a data transfer operation, the tape is moved and re-positioned to rewrite a data block where the error was detected. If the error is not corrected, a minimum threshold requirement is decreased so the system detects the data block as corrected thereby avoiding system hang-ups or the like.

Abstract: Apparatus is provided for switching between recording and playback modes of a tape recorder having a single input/output jack to which an output plug for an earphone, a headphone or the like, or an input plug for a microphone or the like can be connected. The jack is compatible with two channels. When a remote-control unit having a remote-control switch and connected to an input/output transducer is connected to the jack, one channel is used as an input channel for a remote-control signal, and the other channel is used as an input/output channel for an audio signal. In another embodiment, the tape recorder has a control circuit for discriminating between insertion of a 1-channel plug and insertion of a 2-channel plug into the 2-channel jack to control the operation of switches included in this tape recorder.

Abstract: In order to prevent the staining of magnetic heads of a magnetic recorder in a low humidity environment, a refrigeration device which refrigerates a magnetic tape is positioned so as to engage the magnetic tape prior to the tape engaging the magnetic heads. The refrigeration device comprises either a refrigeration post or a refrigerated semi-closed space and functions to transfer water to the magnetic tape.

Abstract: A method of determining the position of a tape in a tape cartridge having a first hub, a second hub, a means for measuring the rotation of the first hub, a means for measuring the rotation of the second hub, and a length of tape with one end of the tape wrapped around the first hub and the other tape end wrapped around the second hub, the tape having a relatively uniform and predetermined thickness and the hubs having predetermined diameters. In accordance with the method, the first hub is locked to prevent rotation of the first hub. A length of tape is then extracted from the cartridge, which causes the second hub to rotate as tape is unwound from the second hub. There is then determined the angle rotated by the second hub in response to the length of tape being unwound from the second hub. The first hub is unlocked and the second hub is locked.

Abstract: Occurrence of mechanical noise and tape damage due to operation of a pinch roller is avoided when the system is switched from the tape playback mode to the radio mode or vice versa. On playback of the tape, an interrupt signal 33 from a microcomputer 34 is low. Transistors 28 and 13 are thus turned on. A drive motor 14 in the tape deck 11 is energized by power from a (+B) terminal 45. When the cassette tape is loaded into the tape deck, a plunger 15 is energized directly by power from a (TAPE+B) terminal 12. Thus, a pinch roller 41 in a head drive mechanism 16 is brought into contact with the tape 43. If the microcomputer 34 detects any interrupt signal such as traffic or emergency information signals multiplexed with FM broadcasting waves, it changes the interrupt signal to high so that the transistors 28 and 13 are turned off. Therefore, the drive motor 14 is de-energized, but the power continues to be supplied to the plunger 15.

Abstract: A system and method for controlling and analyzing data storage systems, and more particularly, to systems and methods for controlling and analyzing performance and physical attributes of a sealed disk drive unit using an externally accessible but internally integral positioning system. A disk drive having a sealed housing utilizes a reflective planar mirror on the rotary actuator controlling the head drive assembly. A narrow beam directed through a window on the side wall of the housing onto the mirror is reflected off at angle dependent on the actuator position to a beam sensitive detector. A translator system driven by a positioner disposed at a distance from the rotary actuator axis which is substantially greater than the distance between the actuator axis and the head assembly, is used to vary the relationship between the directed and reflected beams.

Abstract: The invention provides a device to facilitate precise positioning of a tape head at a particular track on a magnetic tape. Typically, the magnetic tape is adapted to be received in a drive assembly which has a memory and a motor. The device includes a mounting tray for receiving the tape drive assembly, and a laser beam emitted from a laser source. On the tape head of the device, a reflector is positioned and moves with the tape head. Beam directors are provided to ensure that the laser beam passes from the laser source to the reflector. The distance traveled by the tape head from a predetermined point to a position adjacent a track on the magnetic tape is accurately measured, and the extent of movement of the motor required to move the tape head through such a distance is also measured. Thereafter, the measurements are programmed into the tape drive assembly memory.

Abstract: In accordance with an illustrative embodiment of the present invention, a magnetic tape which has seismic data thereon and which has been stored for so long that stiction is a problem is temporarily placed in an environmentally sealed room and subjected to a temperature of about 140.degree. F. and a relative humidity of 20% or less for about 48 hours. After removal from the room and cooling down to ambient temperature of about 70.degree. F. in the presence of relative humidity of about 50%, the tape is cleaned and retensioned on a reel. The data then can be read out onto another media with recovery of practically 100% of the seismic data.

Abstract: A cassette-detection device for use in magnetic tape apparatuses which is provided with a first detection means for detecting the difference in thickness between a cartridge and a cassette shell in order to judge which cassette tape is loaded, an analog cassette tape or a digital cassette tape, and a second detection means for detecting the recessed section of the cartridge of an analog cassette tape in order to judge which side is up with respect to the analog cassette tape. In accordance with the above arrangement, by providing a simple structure, judgement is made as to which cassette tape is loaded, an analog cassette tape or a digital cassette tape, and judgement is also made as to which side is up when an analog cassette tape is loaded.

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: A cleaning apparatus for optical or magneto-optical storage disks includes a first rectangular part having four lateral edges and a raised interior, the interior having at least three troughs for holding utensils for cleaning the optical or magneto-optical storage disks; a second rectangular part having four lateral edges, an interior which is shaped complementary to the interior of the first rectangular part, and a border which runs completely along its four lateral edges for enclosing a disk cassette of a magneto-optical or optical storage disk inserted for cleaning; and a back strap for connecting the two parts to each other such that the two parts can be folded together, similarly to a book, and locked along their lateral edges. The second part further includes a disk bearing which, when the storage disk is inserted, raises the storage disk inside the disk cassette to such an extent that the storage disk is rotatable without friction.

Abstract: The invention is an interlocking lockout device for a computer system. The lockout device comprises a locking disk dimensioned similarly to a floppy disk for so that it can be inserted and locked into a disk-drive. An engagement member of the locking disk interlocks with a bezel. In a locked position, the bezel covers the disk-drive preventing the locking disk from being removed from the disk-drive and preventing foreign matter from being inserted into the computer and disk-drive. While inserted, the locking disk keeps the computer system from booting and thereby prevents unauthorized operation of the computer system. The bezel and locking disk are adaptable on any size disk-drive and can easily be installed on different systems. This provides a lockout capability for computer systems with multiple drives and variable sized disks.

Abstract: A tape recorder used in a telephone message recorder, etc. includes a mode switching mechanism which switches over electrically between various working modes. The mechanism utilizes the operation of one solenoid and the rotational force of a motor, in which the operation of the solenoid is used as a trigger for the mode switching over and the sliding of a head base plate and gear switching are effected by the rotational force obtained through an assist gear.

Abstract: A portable recording and reproducing apparatus is adapted to reproduce a melody recorded on a recording medium such as a magnetic tape and to amplify the melody and voice through a speaker as the voice is inputted from a voice input unit in tune with the melody. The apparatus is formed integrally by incorporating a sound recording medium accommodating portion, the voice input unit, and the speaker via a grip portion, and excels in portability.

Abstract: A magnetic head device includes a rotary cylinder and a magnetic head having one end fixed to an inner portion of one surface of the rotary cylinder such that the magnetic head extends from the inner portion toward the outer circumference of the rotary cylinder in alignment with a radius thereof. The head tip is provided on another end of magnetic head. A laser beam is impinged on the base plate at a portion within a range from 2 mm to (5.times.T1/2)mm from the outer edge of head tip where T is a thickness of the bass plate. The portion on which the beam impinged is heated and melts causing the base plate to incline in a vertical direction which is parallel to an axis the rotary cylinder. Thus, the head tip is positioned at a required horizontal level which is perpendicular to the axis of the rotary cylinder.

Abstract: A floppy disk drive is disclosed which is for use with a host system capable of connecting its own power supply to the disk drive when its operation is needed, and disconnecting the power supply from the disk drive when its operation is not needed. The disk drive includes a stepper motor for moving a data transducer from track to track on a rotating magnetic disk, and a track counter for ascertaining the radial position of the transducer on the disk by counting the stepping pulses fed from the host system to a stepper motor control circuit. In order to maintain the count of the track counter despite power suspension, the track counter is connected to a supply terminal of the disk drive via a reverse blocking diode, and a capacitor is connected between the diode and ground. The track counter is therefore fed from the capacitor when the disk drive is disconnected from the power supply of the host system.

Abstract: A mass storage subsystem is connectable to a host computer via a host adapter and includes a subsystem bus extending from the host adapter to at least one base unit and a removable disk drive cartridge for use with the base unit. A control signal path extends between the base unit and the removable disk drive cartridge when it is installed and connected within the base unit. The disk drive cartridge includes a housing, at least one storage disk rotatably mounted within the housing, at least one data transducer head within the housing and positionable by a head positioner at selected concentric data storage tracks defined on a storage surface of the storage disk. A bus interface circuit is provided for directly connecting to the subsystem bus when the cartridge is installed and connected within the base unit, and a cartridge controller is provided for controlling operations of the bus interface circuit and the head positioner and for communicating with the base unit via the control signal path.

Abstract: A disk drive connected to a host computer compatible with a plurality of computer hardware types can automatically transmit one desired control signal to the host computer, the desired control signal corresponding to a computer hardware type which is being used for the host computer. The disk drive may use a signal transmitted from the host computer which represents a storage capacity of a disk used for the disk drive.

Abstract: A recording and/or reproducing apparatus comprises a display panel which is disposed at such a position as not to face a cassette pressing member between a lid and a holder, thus making it possible to provide display portions by making effective use of a space defined between the lid and holder.

Abstract: A magnetic head position detecting device having enhanced miniaturization and improved measuring accuracy. In the device, the output light beam of a light source is reflected by a first mirror so as to be applied to a rotary drum or the slide contact surface of a magnetic head. The light beam reflected from the rotary drum or the magnetic head is then reflected by a second mirror so as to be detected by a light receiving element. Furthermore, in the device, the output signal levels of a light receiving element corresponding to the position of light beams from the rotary drum and the slide contact surface of the magnetic head are subjected to comparison, so that the amount of protrusion of the slide contact surface of the magnetic head from the rotary drum can be measured with high accuracy.

Abstract: A system for differentiating magnetic recording media of varying shades of black comprises a controller 10, first and second amplifiers 12A, 12B, and first and second fiber optic cables 14A, 14B. The sensitivity of the first fiber optic unit is adjusted such that it detects gamma ferric oxide media but not metal particle or barium ferrite media. The sensitivity of the second unit is adjusted such that it detects both barium ferrite and gamma ferric oxide media, but not metal particle media. The controller employs binary logic to determine which type of media is being viewed by the fiber optic units.

Abstract: A security module for a removable disk drive having a lockable hardware write protect feature for use with docking base. Additional features provided by the invention are an enclosure and electrical connection interface designed to reduce or eliminate radio frequency interference (RFI) and electromagnetic interference (EMI), a removal mechanism that provides for orderly powering down of a disk drive before removal of the security module from a docking base, and a module latching and lock mechanism that provides for positive, lockable securement of the module into a docking base.

Abstract: An apparatus and method for precisely controlling the playback operations of a VCR for transcription purposes by means of a foot-operated remote control containing electronics with timing and delay circuits and programmable read-only memory to generate special sequences and combinations of control signals to the VCR, including a user-controllable variable delay interval function for varying the execution of two or more sequential VCR operations.

Abstract: A disk change signal generating circuit which uses an index sensor includes an index sensor for generating an index pulse in order to detect a rotation of a floppy disk, a timer for inputting the output of the index sensor into a clear terminal and inputting a clock signal into a clock terminal, thereby generating a counting value in a predetermined frequency, and a disk change signal generating circuit for generating a disk change signal by inputting the output of the timer.

Abstract: A method and a device for obtaining a data of tape thinness, in which a calculation is carried out by using information of the changing pulse period based on rotational speed of a tape reel in a take-up side or a supply side, and the number of revolutions of the tape reel and tape velocity. The tape thinness d is obtained by a formula, d=A.times.v.sub.0 (T.sub.T -T.sub.T0)/2.pi..times.n.sub.T, in which, in case of the tape reel in the take-up side, the pulse period of the tape reel is represented as T.sub.T, the initial pulse period of the tape reel is T.sub.T0, the counted number of revolutions of the tape reel from initial setting time is n.sub.T, tape velocity is v.sub.0, and a pole number of the tape reel is A.

Abstract: A receiving apparatus displaying the amount of unrecorded storage medium includes a recording device for recording received data in the storage medium. A display is provided for displaying the amount of recordable, but unrecorded portions of the storage medium upon reception of the received data.

Abstract: A child resistant VCR cover comprises a cover plate having ribs for locating the cover within the video cassette door, a pair of cams which lock the cover in place, grips for rotating the cams, and springs for biasing the cams against the cover plate. The cover is installed by pushing and turning simultaneously the two grips. Each cam has a bevelled surface and acts in a screwlike fashion to engage the interior surface of the VCR frontplate, thereby locking the cover in place. To release the cover, the grips are pushed and rotated until the cams no longer engage the interior side of the VCR frontplate.

Abstract: A video recording and playback device with a built-in video camera includes an outer case having the same profile as that of a tape cassette that can be inserted into an exiting stationary video tape recorder.