Abstract: A magnetic recording/reproducing apparatus equipped with a rotating drum having on its circumferential surface video signal heads for recording and reproducing a video signal on and from a recording medium and PCM signal heads for recording and reproducing a PCM audio signal on and from the recording medium. The apparatus further comprising at least a video signal irregularity detecting circuit for detecting a disturbance of the video signal. When detecting the disturbance of the video signal, the irregularity detecting circuit interrupts the recording of the PCM audio signal onto the recording medium in the case that the apparatus simultaneously records the video signal and PCM audio signal.

Abstract: In a magnetic disk recorder, a displacement of recording timings of a video signal and a timebase-compressed audio signal on a master disk can be corrected on a slave disk. When an output of a master disk reproducing apparatus is a video signal, a vertical synchronizing signal from a synchronizing separating circuit is delayed by a delay time of substantially 7H (H is the horizontal period) and supplied to a phase servo circuit in a slave disk recording apparatus as a reference signal, while when the output of the master disk reproducing apparatus is the timebase-compressed audio signal, a start flag signal accompanying with the timebase-compressed audio signal is detected by a flag detecting circuit and the start flag signal thus detected is employed as a pseudo vertical synchronizing signal, which is supplied to the phase servo circuit in the slave disk recording circuit as a reference signal.

Abstract: An information recording and reproducing apparatus of the rotary head type which is simple in construction and allows, when record data to be re-record are prepared, only the prepared record data to be re-record in a postrecording mode readily. The information recording and reproducing apparatus comprises a digital mixer which replaces data reproduced from a selected portion of a recording medium with record data to be re-recorded, and the resulted data are supplied by way of a recording circuit to a pair of recording magnetic heads so that they are recorded to the selected portion of the recording medium. The recording magnetic heads are mounted on a rotary head at mounting heights lower than a pair of recording and reproducing magnetic heads disposed on the rotary head.

Abstract: An information signal recording and reproducing apparatus having a reproducing head at a position anterior to a recording head by a distance corresponding to a predetermined time interval for recording an information signal on a recording medium and reproducing the recorded information signal. A test pattern signal is generated and delayed in a delay circuit by an amount determined by a control signal. An external delay-factor device receives the delayed test pattern signal and imposes a further delay thereon. The phase of the delayed signal from the external delay-factor device and the phase of the test pattern signal are compared and the control signal is generated, such that the sum of the amounts of delay imposed by the external device and the delay circuit becomes coincident with the predetermined time interval. Thus, the desired phase adjustment can be automatically and rapidly achieved with precision.

Abstract: A method of controlling the gain of a read amplifier preparatory to writing data on a length of multitrack magnetic tape, by writing and reading in a read-while-write mode a reference pattern on the tape immediately when the tape starts running. The gain of the read amplifier is automatically controlled so that the output therefrom, representative of the reference pattern read on the tape, may have a magnitude within a predetermined range. The gain control procedure is retried up to a predetermined number of, say, fifteen if the output magnitude of the read amplifier fails to come up to the predetermined range. If the failure in gain control is due to dust accumulation on the tape or on the transducer, the reference pattern is increasingly more likely to be written and read properly during the retries because the dust may be removed by relative sliding motion between the tape and the transducer.

Abstract: A digital VTR is provided with a block segmenting circuit for converting an input digital picture signal into data segmented into blocks of picture elements, an encoding circuit for compressing and encoding the output data of the block segmenting circuit block-by-block, a channel encoding circuit for channel encoding the encoded output data from the encoding circuit, an audio signal encoding circuit for encoding an input digital audio signal, and an additional code generating circuit for generating an additional control code which includes subdata.

Abstract: An apparatus for generating a high speed dubbing signal to be recorded by an external recording apparatus. The high speed dubbing signal, whose pitch is N times that of a digital input signal, is generated as follows. An encoding circuit subsamples the digital input signal consisting of frame signals each of which consists of N field signals, so that each frame signal is compressed by a factor of N to be contained in one field interval. A digital signal recording and reproducing circuit including a recording and reproduction system, records on a tape, at a normal tape speed and at a normal head drum rotational frequency, the compressed signal in such a manner that each field including the compressed signal appears once per frame interval, and then selectively reproduces from the tape the field including the compressed signal at a tape speed N times the normal speed and at the normal drum speed.

Abstract: Methods and apparatus are provided for recording and reproducing digital information signals including image and audio portions in successive tracks on a magnetic tape. An ID signal is produced for one of an image portion and an audio portion of a corresponding digital information signal to be recorded. The ID signal indicates whether the portion is to be after-recorded in a respective track. The ID signal is combined with the portion to form a recording signal. Previously recorded digital information signals are reproduced from the track and an ID signal thereof is obtained. The recording of the portion in the track is controlled based on the reproduced ID signal.