Abstract: A device for switching a coil between a first state where it is connected between a supply source and the ground through an impedance and a second state where it is connected between an output terminal and the ground, a first switch (T.sub.REC) being arranged between the output terminal and the supply source. This switching device comprises: a diode (14) connected between the output terminal (16) and the supply source, a controlled switch (T.sub.PB) connected in parallel with the impedance between a second terminal of the coil and the ground, and a detection and control means (20, 24) connected between the diode and the power supply source for detecting the time when the voltage between the diode and the ground becomes equal to a predetermined value lower than the forward voltage drop across the diode and for thereby controlling said switch.

Abstract: A rotary head type reproducing apparatus having a reproducing rotary head for reproducing signals recorded on a recording medium and a rotary erasing head for erasing signals recorded on the recording medium, both heads being mounted on a rotary member, wherein a reproduction amplifier for amplifying a reproduced signal reproduced by the rotary reproducing head is put on the rotary member and supply of electrical power to the reproduction amplifier is made through a rotary transmitter which, when erasing, transmits an erasing signal to the erasing head therethrough.

Abstract: An analog signal digitizer for recording analog signals in a digital form on a video tape of a video cassette player. The digitizer is connectible between an audio production device, such as a compact disc, turntable, or any other audio devices of any quality, and a standard video recorder (VCR). Accordingly, the digitizer acts as an interface device, and converts the analog signals into digital form for recording on the wide band tapes utilized in these standard video recorders. The digitizer has a control circuit at the heart of its system, and it is provided with a memory device to produce control signals in association with audio information digital signals, and arranges these digital signals in a sensitized video-compatible format so that the video cassette treats the output signals of the digitizer as standard television signals.

Abstract: A recording and reproducing system for performing a read-after-write operation, and for performing automatic tracking. The system includes a magnetic head for recording/reproducing information from/onto a tape. The magnetic head has a first gapped portion and a second gapped portion. The system further includes a reading circuit for reading information recorded on the tape, a writing circuit for writing information onto the tape, a changing device for selectively connecting the first gapped portion to either the reading circuit or the writing circuit, and for selectively connecting the second gapped portion to either the reading circuit or the writing circuit, and a comparator for comparing the outputs from the first and second gapped portions when the first and second gapped portions are each connected to the reading circuit by the changing device, and for outputting a signal representative of that comparison.

Abstract: A control circuit for a recording and reproducing apparatus. The circuit includes a single magnetic head for recording and reproducing signals corresponding to data on a recording medium, a recording circuit for supplying a recording signal to be recorded to the magnetic head, a reproducing circuit for amplifying a reproduced signal detected from the recording medium by the magnetic head; and a switch for selectively shifting the apparatus between a recording phase wherein the recording circuit is activated, and a reproducing phase wherein the reproducing circuit is activated, wherein the reproducing circuit includes capacitors for storing an electric charge during operation of the apparatus, and buffers for maintaining the charge stored by the capacitors at a substantially constant level when the switch shifts between the recording phase and the reproducing phase.

Abstract: A data separator system has a PLL circuit for out-putting data pulses and clock pulses on the basis of the read data from a magnetic recording medium. The system also includes an external synchronization detection circuit which detects the synchronization data (predetermined zero pattern data) recorded in the synchronization area of the magnetic recording medium, on the basis of the read data. When detecting the synchronization data, the synchronization detection circuit enables the PLL circuit to oscillate in synchronism with the read data. The data pulses and clock pulses output from the PLL circuit are also supplied to an internal synchronization detection circuit. On the basis of the data pulses and the clock pulses, the internal synchronization detection circuit detects the synchronization data, and upon detection thereof, a floppy disk controller performs the data readout operation.

Abstract: An apparatus for recording or reproducing information on or from a magnetic recording medium by means of a magnetic head, including means for effecting change-over of recording mode and reproducing mode, which is provided with a circuit for preventing variation of DC potential near a change-over point at the time of the change-over to prevent damage of information previously recorded on the recording medium by transient current flowing through the magnetic head and a DC setting capacitor connected in series with said head at the time of said change-over or a circuit for producing said change-over after electric charge stored in a DC component cutting capacitor has been discharged.

Abstract: An apparatus having an UP and DOWN switches which enable the user to set photographing conditions or parameters of the photographing condition, and which has a reproducing function by itself or by connection to an external device through an adapter. The UP and DOWN switches also enable the user to effect the frame or track feed for allowing a head to make an access to a desired track during reproduction.

Abstract: The present invention relates to a control circuit for a double deck cassette tape recorder, and comprises switches, resistors, transistors and diodes. A plurality of transistors control the specific circuitry functions of the tape recorder. These transistors are in turn controlled either by switches, directly or indirectly, through other transistors. The present invention offers advantages such as simple structure, low production cost, ease of operation and prevention of confusion or mistakes in operation.

Abstract: A magnetic disk drive of the type comprising at least one read/write head assembly having a read/write coil which is center-tapped to provide a pair of coil halves which are alternately excited during writing, and a write terminate resistor connected between the coil halves for preventing the flow of oscillatory current therethrough during writing. In order to electrically isolate the write terminate resistor from the read circuit also coupled to the opposite extremities of the read/write coil, alternating-current switches are connected between the write terminate resistor and the read/write coil so as to be away from the paths of write current through the coil. The alternating-current switches are rendered conductive only during writing.

Abstract: A tape recorder comprising a cassette tape compartment for detachably housing a first and second cassette tapes, a capstan for driving the first and second cassette tapes coaxially mounted thereon, a mode selector member for selecting the driving mode for the first and second cassette tapes, operation means for causing the second cassette tape to perform a first or a second function and causing the first cassette tape to perform the first function, a device for allowing the second cassette tape to achieve the first or second function, in response to operation of the operation means corresponding to the first or second function, when the second cassette tape-driving mode has been selected by the mode selector member, a device for allowing the first cassette tape to achieve the first function, in response to operation of the operation means corresponding to the first function, when the first cassette tape-driving mode has been selected by the mode selector member, and a function blocking device for hindering th

Abstract: With the inventive method, after a servo pattern data including index pattern is written onto the servo disk in a magnetic disk unit, a variety of software processes is effected thereafter, and the servo pattern data having been written is read and the index pattern is detected, a varify data is outputted, the comparison between the read index pattern data and the verify data is started, thereby verifying the validity of the writte servo pattern data. More particularly, immediately after completion of said variety of software processes and without waiting for the revolution of the servo disk, the verify data is compared with the read servo pattern data, whereby the write of servo pattern data onto the magnetic disk and the read verify process can be effected speedily.

Abstract: At least two operation buttons are arranged to set one of a plurality of operation modes of a recording/reproducing apparatus. When each operation button operated a plurality of times within a predetermined period of time is detected by a microprocessor, a switching circuit sets a recording medium in a predetermined operation mode determined by the operation/non-operation and the number of operations of each operation button. In the predetermined operation mode, at least one recording medium mounted in the recording apparatus is erased while being rewound or fast forwarded.

Abstract: In rotating mass memories, for example magnetic disk memories, write or, respectively, read operations are controlled by a static status signal. A plurality of read heads having assigned preamplifiers is selectively activatable with the assistance of a selection signal and is through connectible to a common signal shaping device for further amplification and filtering of the read output signal. The signal shaping device has an input stage assigned thereto in which the differential outputs of the preamplifiers are respectively connected in parallel to the signal shaping device via a respective coupling capacitor. The input stage also comprises first analog switches arranged between an operating voltage and the coupling capacitors and comprises second analog switches in series in the signal lines.

Abstract: An information recording system comprising a read/write device including a read/write head for reading and writing information from and on a rotatable data-storage medium rotated by a first drive motor, and electrically operated elements such as a second drive motor for moving the read/write head relative to the data-storage medium, reading and writing amplifiers, and detectors for sensing operating conditions of the recording system such as the angular position of the data-storage medium. Electric power is supplied to such electrically operated elements from a power source via power disconnect switches connected between the power source and the respective electrically operated elements for selective power supply to the individual elements.

Abstract: An apparatus has a part which can be moved to an operating position by an actuating device, in response to movement of a button to an on position. Upon movement of the part to its operating position, a latching member directly associated with the part latches the button in its on position. Upon sensing a predetermined condition in the apparatus, a control member prevents the transmission of the actuating movement by the actuating device to the part, and a user becomes aware that the part has not moved to its operating position because the button does not become latched in its on position.

Abstract: A magnetic head switching circuit for a magnetic recording and reproducing apparatus having a recording and reproducing magnetic head has three switching circuits. The first switching circuit is coupled between ground and one end of a winding of the head and controlled between conducting and non-conducting states in response to a voltage applied to a first control terminal. The second switching circuit has an output end, an input end coupled to a D.C. power source, and a second control terminal supplied with a mode switching signal for assuming a non-conducting state in the recording mode and assuming a conducting state in the reproducing mode to guide a voltage at the input end to the output end in response to the mode switching signal. The third switching circuit has an input end coupled to the output end of the second switching circuit and an output end coupled to the first control terminal.

Abstract: In an apparatus in which a video signal can be reproduced from a magnetic tape that is transported with a different tape speed from that in recording, such as, in a slow or still reproducing mode, and the reproduced video signal and an input video signal can be alternatively supplied to an output terminal at every predetermined number of field intervals, there is provided a circuit for controlling a time axis of the input video signal so as to be substantially equal to the time axis of the reproduced video signal.

Abstract: A magnetic recording and reproducing apparatus which comprises recording and reproducing means including a magnetic recording/reproducing head and a capacitor connected in series to one end of the head winding to remove the DC component of a recording current flowing to the head; recording/reproduction switch-over apparatus including first and second switching circuits which are respectively grounded on the sides opposite the sides associated with the wiring of the head; and inhibiting apparatus for inhibiting the recording/reproduction switch-over apparatus from operating as a result of a variation in the potential of one terminal of the capacitor.

Abstract: A motor of a motor drive mechanism is driven by a logic control circuit and a motor driving circuit when an operating member for tape feed is operated. A shift control mechanism receiving a forward or reverse rotatory force from the motor controls a pinch roller included in a tape drive mechanism for a specified condition by means of a playback slider, and also controls a head to a predetermined position by means of a head slider. Thus, the motor drive mechanism can establish a forward or reverse tape feed mode in a tape recorder.

Abstract: A magnetic head has three pole pieces that form a magnetic circuit. The magnetic pole pieces are arranged in a common plane so that the two outside pole pieces are each spaced from the central pole piece to form a transducing gap between each of the outside pole pieces and the central pole piece. A first and a second coil, each having the same magnetic sense, is wound on the magnetic structure between an outside and the center pole piece. The coils are connected in series for a write operation so that the flux in the outside pole pieces is additive for writing, and the coils are connected in series opposition for a read operation so that the flux produced in the center pole by a previously recorded magnetic transition in the magnetic recording medium adjacent to the transducing gaps is sensed additively in the coils.

Abstract: A signal transmission circuit includes a switched capacitor and a control circuit. The switched capacitor includes a capacitor and a plurality of switching means. The control circuit controls the frequency or level of a control signal to be applied to the switching means of the switched capacitor. By varying the frequency of the control signal with the control circuit, the equivalent resistance of the switched capacitor can be varied. By controlling the level of the control signal with the control circuit, at least one of the plurality of switching means is held in the "off" state thereof, to substantially inhibit the signal transmission of the switched capacitor.

Abstract: A floppy disk driving circuit comprises a memory circuit for storing a plurality of items of delay time of a pair of erase heads from the switching-ON and the switching-OFF of a read/write head for all the tracks of a floppy disk, a control circuit responsive to the memory circuit for controlling ON- and OFF-delay timing of the pair of erase heads based on the plurality of items of delay timing. The plurality of items of suitable timing are previously calculated in connection with the respective tracks of the disk and stored within the memory circuit.

Abstract: The rotating-head PCM record/reproduce apparatus has record and reproduce heads of which the reproduce heads are disposed to scan the recorded track formed by the record heads with a delay of a rotation angle of 90.degree. thereby reading immediately after recording, and circuits for converting analog signal to digital signal, and for compressing the timebase of the digital signal, the compressed digital signal being supplied to the record heads so that no signal is supplied to the record head while the reproduce heads are reading the recorded signal.

Abstract: Circuit means for recorders in which the same external pin receives a play signal, a record signal, and a noise reduction signal generated by a user. The circuit means is comprised of a differentiating means for receiving the play and record signals and differentiating between them. A memory means is connected to the differentiating means and stores an indication of the last received of the signals. A first switch means is connected to the memory means and is operable to a first condition to control the play function when the memory means indicates the play signal was last received and to a second condition to control the record function when the memory means indicates the record signal was last received. A second switch means is connected to the external pin receiving the noise reduction signal and generating an ouptut signal to turn on noise reduction means during either the play or record mode.

Abstract: In an apparatus having a record mode for recording video or other information signals in successive parallel information tracks on a record tape by means of a plurality of rotary heads repeatedly scanning across said tape and having respective gaps with different azimuth angles, and in which the apparatus is changeable to a playback mode for causing each of said heads to provide a respective output when it is scanning an information track in which information signals have been previously recorded by a head with a gap having the same azimuth angle; clogging of one or more of the head gaps which would prevent further recording is detected, in the playback mode, by switching from one to another of the outputs of the heads during each period required for the scanning of the tape by each of the heads, detecting the levels of the head outputs during such switching therebetween, and operating a clog indicator when the detected levels of the head outputs are insufficient during the scanning of the tape by each of the

Abstract: A portable tape recorder for remote location news-gathering including a rugged metal housing having operating controls and input-output connections located at one end for ease of access. An audio output suitable for direct interconnection to telephone circuitry is provided in addition to internal speaker and external headset audio output connections. A talk-over preamp operatively interconnects the microphone or other audio input to the recorder output when the recorder is in the pause mode facilitating the use of the recorder microphone for direct telephone line connection. This permits live reporter commentaries, introductions, or `wrap-arounds` to be conveniently interspersed with pre-recorded news story segments. The speaker audio output is muted in the talk-over mode to preclude acoustic feedback while reporter `side-tone` monitoring is available through the external headset or telephone handset connections.

Abstract: A magnetic recording/reproducing apparatus has a rotor drum with a group of rotary magnetic heads mounted thereon, a reproducing amplifier, a recording/reproducing mode switching circuit, a head selection circuit, a control circuit and a DC voltage source. The control signal circuit and the DC voltage source receive a control signal transmitted from a stator drum through a rotary transformer and produce signals for controlling the mode switching circuit and the head selecting circuit and a DC voltage for energizing all the circuits on the rotor drum, respectively.

Abstract: A mode switching circuit is for use in a reproducing apparatus, and comprises a rotation detecting circuit for detecting the rotation of a rotary body which rotates according to a moving tape, a plunger solenoid for driving a plunger which switches the operating state of the reproducing apparatus to a state which is in accordance with the moving mode of the tape, an unrecorded band detecting circuit for detecting an unrecorded band from the tape which moves in a fast-forward mode during a program selecting mode of the reproducing apparatus, a control circuit coupled to the rotation detecting circuit and to the unrecorded band detecting circuit, and a feedback path coupled from a connection point between the control circuit and the plunger solenoid to the rotation detecting circuit through a resistor.

Abstract: A switching circuit for AC bias signal has an input terminal for inputting an input signal into the switching circuit and a first transistor connected to the emitter of the input terminal. A second transistor is connected at the collector to the collector of the first transistor. The emitter area of the second transistor is larger than that of the first transistor so that the dynamic resistances of the these transistors are equal to each other when these resistors are ON state. The emitter of the second transistor is connected to the reference voltage terminal supplied with ground voltage. The first and second transistors are controlled in conduction by a control signal as input.

Abstract: A dictating machine having a revising function, records a correction signal onto a magnetic tape in superimposition with an originally recorded content when correcting the originally recorded content or adding a content to the originally recorded content so as to accurately indicate a position where the correction or the addition is required, without erasing the originally recorded content. The dictating machine is capable of recording a new content onto the magnetic tape with a large degree of freedom without erasing the originally recorded content, because the new content is recorded on a track on the magnetic tape which is different from the track on which the original contents are recorded.

Abstract: A position control system for controlling a motor-driven mechanism capable of occupying a plurality of specified positions comprises a plurality of switches for specifying a position to be occupied by the mechanism and an encoder for generating a specified position signal representative of the specified position and a loading circuit for providing a present position signal representative of the position presently occupied by the mechanism. A read-only memory circuit uses the specified and present position signals to provide a control signal for controlling the motor to move the mechanism to a particular position and a comparison signal and a particular position signal indicative of that particular position. A position detector responsive to the position of the mechanism provides a detection signal representative of the particular position when the mechanism reaches it.

Abstract: A tape recorder capable of performing simultaneous recording or reproducing operation and dubbing operation easy is disclosed. The tape recorder comprises a dubbing means for simultaneously operating a reproducing operation means for one tape drive mechanism and a recording and reproducing operation means for the other drive mechanism or an operation interlock means for simultaneously operating a pair of pause operating means.

Abstract: Tape recorder apparatus includes an amplifier section and a tape deck section which is selectively attachable to and detachable from the amplifier section. The amplifier section includes a muting circuit which is connected to an amplifier bias circuit and is adapted to be connected to a switch circuit in the tape deck section when the tape deck section is connected to the amplifier section. When the two sections are connected, the switch circuit supplies a muting release instruction to the muting circuit in the amplifier section for normal amplifying operation and, when the two sections are disconnected from one another, the muting release instruction from the switch circuit in the tape deck section is withheld from the muting circuit in the amplifier section, thus disabling the amplifying function of the amplifier section by causing a change in the bias potential supplied by the amplifier bias circuit.

Abstract: This invention is an automatic read to write or write to read switching electronic recording and playback circuit that automatically disconnects the write section of the circuit when it is not in use, thus permitting reading without the necessity of an additional signal to select read or write.

Abstract: In a mass storage system, a method for controlling the stepping feed of an information medium (T) on which recording tracks are formed by stripes (T.sub.n) which run diagonally or vertically across the information medium is disclosed. According to this method, the feed of the information medium (T) begins after the completion of the recording or reading operation of data (DATA) upon a first recording track (T.sub.n) and prior to the completion of the checking of the content of the data (DATA). After that, it is determined whether the feed of the information medium is continued or reversed should be in accordance with the result of checking the content of the data (DATA). That is, when no error is detected as a result of the checking, the feed is continued so as to perform the recording or reading operation of data (DATA') upon a second recording track (T.sub.n+1).

Abstract: In the disclosed system, a large scale integrated circuit receives operating signals from record, play, stop, fast-forward, and rewind actuating switches at corresponding input terminals and produce motor forward and reverse signals for controlling switches that operate a motor, fast-forward signals, and amplifier control signals at corresponding output terminals. Outside the LSI, a feedback arrangement responds to a tape-stop signal indicating that the tape has stopped advancing, and the motor forward signal produced by the large scale integrated circuit to apply play and rewind signals to the input terminals of the circuit whether or not the rewind or play switches have been operated.

Abstract: A magnetic tape recording and playback apparatus, selectively changeable between recording, playback, and stop modes, includes a recording/playback transducer, a line amplifier connected during recording to amplify the signal to be recorded by the transducer and during playback to amplify the signal picked up by the transducer; a power amplifier to amplify the signal provided by the line amplifier to drive an acoustic transducer; and a level indicator for selectively indicating the output level of the line amplifier and of the power amplifier. A switch circuit automatically connects the level indicator to the line amplifier when the recording mode is selected and to the power amplifier when either the playback or stop mode is selected. When the apparatus is in the playback mode, the level indicator can be coupled to the line amplifier by actuation of a push button or other manual switch.

Abstract: A servo system provides track following servo information from a buried servo layer disposed under the data recording layer, using the same transducer for simultaneously reading the servo information and writing data. To prevent the voltage generated in the transducer while writing data from masking out the servo information, a dummy voltage having the same magnitude as the transducer voltage is connected so that it cancels the write data voltage in the head.

Abstract: A magnetic tape recorder of the type wherein tape is transported at high speed during recording and at low speed during playback is described. The recorder has separate record and playback heads. To prevent the shallow-gapped playback head from being worn out by, and during, the high speed recording operation, the playback head is disposed to fly the tape at an appreciable distance from the playback head. During low speed playback of the tape, however, tape flight vis-a-vis the playback head is desirably miniscule.

Abstract: An operating mode change-over apparatus in a tape recorder includes: a plunger-solenoid having a stationary iron core and a movable iron core movable from a first position in contact with, and a second position spaced from, the stationary iron core; an electric motor; a pinion driven by the electric motor; a rack engageable with and disengageable from the pinion; an operating mode change-over member driven by the rack; a locking lever driven by the movable iron core and holding the engaged condition of the rack and pinion; and a spring for pressing the movable iron core to the stationary iron core, wherein, while the movable iron core is pressed to the stationary iron core, the plunger-solenoid is energized, and the electric motor is driven.

Abstract: A magnetic tape device having two independently operative tape transports incorporated in one common deck which comprises means for selectively performing recording by a first transport in combination with reproducing by a second transport and reproducing by the first transport in combination with recording by the second transport, and means for recording a reproduced signal from either one of the transports on the other transport through a common reproducing and recording process circuit, thereby to effect dubbing in either direction.

Abstract: A sound dubbing control for a videotape recorder includes a mechanism which enables it to be automatically locked in operating condition when the playback control is subsequently actuated; the dubbing control is automatically released when the playback control is released. The dubbing control and playback control each include a slidable member one of which moves transversely with respect to the other and the member for the dubbing control is provided with a leaf spring having parallel arms. One of the arms has a hook-shaped end which catches on a projection on the playback member when the dubbing member is advanced into the path of the playback member. This action also causes the other arm of the spring to actuate a switch controlling the sound dubbing circuit.

Abstract: A mode switching circuit has external terminals, a mode selection means for selecting a mode in accordance with the kind of a signal applied to the terminals, and a means for designating a mode selection state in the mode selection means by a mode selection signal. The external terminals are used commonly for a plural kinds of signals.

Abstract: An operation mode display apparatus comprises first and second display means (LED1 and LED2) capable of being operated independently of each other and a display state specifying means for specifying the display states of said first and second display means corresponding to an operation mode of a tape recorder. At least three operation modes of said tape recorder can be displayed by corresponding combinations of the display states of the first and second display means (LED1 and LED2).

Abstract: A miniature tape recorder with a two-channel magnetic head and a selecting member for selecting one of combinations of channels for recording and reproducing without releasing a record-actuating member and a reproduction-actuating member, which tape recorder can be used to form an inexpensive study machine by connecting it to an outside study unit for using a two-channel study tape, wherein study step cannot proceed unless a student thoroughly understands the answer to the question of one study step.

Abstract: The disclosed data recorder utilizes a common tape recorder to which a computer unit is docked. In the computer unit, a display indicates if the reproducing or recording mode of the tape recorder is correct so that an operator may change the recorder operating mode.

Abstract: An operation mode switching system for a tape recorder in which the tape recorder is set to a recording-pause mode by operating a REC. STBY. (recording stand-by) key when the tape recorder is in a stop mode, set to a recording mode by operating a PLAY key when the tape recorder is in the recording-pause mode, and set to a playback mode by operating the PLAY key when the tape recorder is in a stop, fast-forward or rewinding mode.

Abstract: This invention relates to a magnetic recording and reproducing device in which automatic settings of optimum recording bias current, optimum recording level and optimum recording equalization characteristic are successively accomplished in this order. The settings of the optimum recording conditions are achieved with high accuracy within short period of time by a computer control using a microprocessor.

Abstract: A cassette type tape recorder provided with a manually operated control member for operating a record circuit when the tape recorder is to be set in the record mode, and a main control member to be switched over and set in play, stop, and rewind positions, further comprising a lock mechanism for locking the record control member in the operative position, a mechanism for setting said main control member in a specific position between play position and rewind position, a mechanism for releasing said lock mechanism when said main control member is manually operated to a position set by said setting mechanism, and a rewind mechanism which operates when said main control member passes the position set by said setting mechanism and is set in rewind position. In accordance with this structural organization, it becomes possible to release the locked record control member without any accidental rewinding of tape.