Victor Company of Japan, Limited

Akira Hirota

Takuya Tsushima

Yoshihiko Ota

Yoshiteru Kosaka

Seisuke Hiraguri

Masahiko Tsuruta

Takashi Uchimi

Yutaka Ichinoi

Naomichi Nishimoto

Seiji Higurashi

Yasutoshi Matsuo

Hiroyuki Miyahara

Hidetoshi Ozaki

Noboru Watanabe

Masato Mihara

Kenji Shibayama

Hiroyuki Kitamura

Osamu Inoue

Koichi Kido

Kazutaka Ashida

Shinji Hirano

Yoshimichi Nagaoka

Yuma Shiraishi

Masaharu Tsunekawa

Nobuyoshi Suzuki

Masajhi Yoshida

An apparatus for producing a frequency-multiplex signal on the basis of a plurality of signals so as to record the produced frequency-multiplex signal on a recording medium, second signal having a frequency lower than that of the first signal. The apparatus includes a multiplying circuit for multiplying the frequency of the second signal by 2 and an amplitude-modulator for multiplying the first signal by the output signal of the multiplying circuit. Also included in the apparatus is an adder for adding the second signal to the output signal of the amplitude-modulator, the output signal of the adder being recorded as the frequency-multiplexing signal on the recording medium.

Recording of frequency-multiplex signal on recording medium

A magnetic tape is wound on a rotary drum through a predetermined angular range greater than a standard tape winding angle. The predetermined angular range has a first portion corresponding to the standard tape winding angle and a second portion extending outward of the first portion. A main information signal is recorded into a main information recording track on the magnetic tape which extends in a region corresponding to the first portion of the predetermined angular range. A sub information signal is recorded into a sub information recording track on the magnetic tape which extends along an extension line of the main information recording track and which extnds in a region corresponding to the second portion of the predetermined angular range. A plurality of magnetic heads have different track widths respectively and are mounted on the rotary drum. The magnetic heads form respective different tracks which together constitute the sub information recording track.

Magnetic video tape recording and reproducing apparatus

A helical scan type magnetic recording and reproducing apparatus comprises a rotary body which is wrapped with a magnetic tape on an outer peripheral surface thereof over a predetermined angular range and has a tape guide for guiding a part of the magnetic tape, and n pairs of rotary heads mounted on the rotary body. Each pair out of the n pairs of rotary heads is constituted by two rotary heads which are mounted at mutually opposite positions on a rotational plane of the rotary body at the same height position, and each pair out of the n pairs of rotary heads is mounted at different positions in an axial direction of the rotary body. The n pairs of rotary heads simultaneously record a luminance signal and two kinds of signals constituting a color video signal on n groups of tracks which are mutually separated in the tape width direction, so that the luminance signal is recorded on one group of tracks which is closest to the tape guide of the rotary body in order to minimize a jitter in the luminance signal which is reproduced.

Helical scan type magnetic recording and reproducing apparatus recording

A magnetic recording apparatus for carrying out a recording by selectively using one of two kinds of recording systems comprises first through fourth rotary magnetic heads, a first circuit for producing an FM luminance signal, second and third circuits for producing first and second frequency division multiplexed signals, and a switching circuit. The first and second heads are mounted on a rotary body at mutually opposing positions, and have the same height position. The third and fourth heads are mounted on the rotary body at mutually opposing positions respectively in vicinities of the first and second heads along a rotating direction of the rotary body, and have the same height position. The switching circuit selectively supplies the output signals of the first and second circuits to the first through fourth heads when a luminance/color separation recording system is selected as the recording system, and selectively supplies the output signal of the third circuit to the first and second heads or to the third and fourth heads when a low band conversion color recording system is selected as the recording system.

Magnetic recording apparatus for carrying out recording by selectively

A video signal recording and reproducing apparatus comprises a first sampling circuit for sampling a recording video signal which has a band with an upper limit frequency f.sub.a and is to be recorded by a sampling signal having a frequency f.sub.s, where the frequencies f.sub.a and f.sub.s satisfying a relation f.sub.a &lt;f.sub.s &lt;2f.sub.a and an equation f.sub.s =(2n+1)f.sub.H /2, n is an integer, and f.sub.H is a horizontal scanning frequency of the recording video signal, a recording and reproducing circuit for recording an output signal of the first sampling circuit on a recording medium and for reproducing the signal from the recording medium, a delay circuit for delaying the signal which is reproduced from the recording medium by the recording and reproducing circuit by a delay time of one horizontal scanning period, a second sampling circuit for alternately sampling input and output signals of the delay circuit by a sampling signal having the frequency f.sub.s, and an adding circuit for adding alternately sampled signals from the second sampling circuit, and for obtaining a reproduced output signal which has essentially been sampled at a frequency of 2f.sub.s.

Apparatus for recording a video signal sampled at frequency f.sub.s and

A video signal reproducing apparatus comprises a reproducing circuit for reproducing from a recording medium a pre-recorded video signal having field correlation and having a predetermined band, and a noise reduction circuit supplied with a reproduced video signal from the reproducing circuit for essentially reducing noise included within the reproduced video signal. The noise reduction circuit comprises first and second subtracting circuits supplied with the reproduced video signal from the reproducing circuit, a one-field delay circuit for delaying an output of the first subtracting circuit by a predetermined time period and for supplying a delayed signal to the second subtracting circuit, which predetermined time period is equal to one field or a time period which is a natural number multiple of one horizontal scanning period and is extremely close to one field, and a limiter for amplitude-limiting an output of the second subtracting circuit and for supplying an amplitude limited signal to the first subtracting circuit. The output of the first subtracting circuit is obtained as an output of the noise reduction circuit. The one-field delay circuit has a transmission band which is narrower than a band of the reproduced video signal.

Video signal reproducing apparatus having a noise reduction circuit

A carrier chrominance signal recording apparatus comprises a first circuit for sampling a carrier chrominance signal at a sampling frequency which is four times a chrominance subcarrier frequency, and then quantizing the sampled signal so as to produce a first digital color signal, a second circuit for subjecting the first digital color signal to a phase shift process so as to produce a second digital color signal related to a carrier chrominance signal in which the phase of a chrominance subcarrier is equivalently and successively shifted by approximately 90.degree. in a predetermined direction for every one horizontal scanning period, a third circuit for converting the output second digital color signal of the second circuit into a frequency converted digital color signal which is in a low-frequency range, a circuit for obtaining an analog frequency converted carrier chrominance signal by subjecting the frequency converted digital color signal to a digital-to-analog conversion, and a circuit for recording the analog frequency converted carrier chrominance signal on a recording medium. A reproducing apparatus reproduces the signals recorded on the recording medium by the above recording apparatus.

Chrominance signal recording apparatus utilizing digital sampling and

A video signal recording and reproducing apparatus comprises a circuit for generating a first signal having a sampling frequency f.sub.s which is approximately a natural number multiple of a horizontal scanning frequency f.sub.H of an input composite video signal and satisfies f.sub.s .apprxeq.f.sub.L +f.sub.U and having a phase which differs by 180.degree. for every one field, where f.sub.L represents a constant frequency in the range of 0.5 to 1 MHz and f.sub.U represents an upper limit frequency of a band required for a reproduced composite video signal, a circuit for sampling a signal part of the input composite video signal at least excluding synchronizing signal intervals thereof by the first signal, a circuit for recording and reproducing the sampled signal on and from a recording medium, a circuit for obtaining from the reproduced signal first and second reproduced sampled signals having a mutual time difference of one field, a circuit for generating from the reproduced signal a second signal having the frequency f.sub.s and having a phase which differs by 180.degree. for every one field, and a circuit supplied with the second signal for alternately and selectively passing the first and second reproduced sampled signals for every 1/2 period of the second signal so as to obtain a reproduced composite video signal which has been re-sampled.

Video signal recording and reproducing apparatus

A rotary transformer is employed in a 4-head type recording and/or reproducing apparatus which has a rotary body which is wrapped with a magnetic tape, and four heads mounted 90.degree. apart from each other on the rotary body for recording and/or reproducing a video signal onto and/or from the tape. The rotary transformer device comprises a rotary core which has five circular grooves formed in one surface thereof and is rotated unitarily with the rotary body, a first short-circuiting ring embedded in a center groove among the five grooves of the rotary body, first through fourth ring-shaped coils embedded in the remaining four grooves of the rotary body, a stationary core which is stationary at a location separated from and opposing the rotary core and has five circular grooves, a second short-circuiting ring embedded in a center groove among the five grooves of the stationary core, and fifth through eighth ring-shaped coils embedded in the remaining four grooves of the stationary core. The first and second ring-shaped coils which are located on one side with respect to the first short-circuiting ring, are coupled to one pair of mutually opposing heads among the four heads. The third and fourth ring-shaped coils which are located on a side opposite from the one side with respect to the first short-circuiting ring, are coupled to the other pair of mutually opposing heads.

Combination of reproducing heads and a rotary transformer device

A video signal delay circuit comprises an input horizontal transfer register supplied serially with an input composite video signal, an input vertical transfer gate, a plurality of columns of vertical transfer registers, an output vertical transfer gate, an output horizontal transfer register, a horizontal transfer clock pulse generating circuit, a vertical transfer clock pulse generating circuit and a vertical transfer gate pulse generating circuit. The vertical transfer clock pulse generating circuit generates a vertical transfer clock pulse at a rate of once per one horizontal scanning period of the input composite video signal and additionally generates one or more vertical transfer clock pulses during a specific time period. Or, the horizontal transfer clock pulse generating circuit generates a horizontal transfer clock pulse having a selected phase or a selected number of horizontal transfer clock pulses.

Video signal delay circuit

A cue signal recording circuit for a magnetic recording and reproducing apparatus comprises an erase signal generator for generating an erase signal having a relatively high frequency, a symmetry varying circuit responsive to a first external signal having a relatively low frequency for varying the symmetry of the waveform of the output erase signal of the erase signal generator at the relatively low frequency, a switch having a first input terminal applied with the output erase signal of the erase signal generator and a second input terminal applied with an output signal of the symmetry varying circuit, where the switch is connected to the second input terminal so as to pass the output signal of the symmetry varying circuit for a predetermined short time period and is thereafter connected to the first input terminal so as to pass the output erase signal of the erase signal generator responsive to a second external signal, and an erase head supplied with the output signal of the switching for recording on a magnetic tape a signal having the relatively low frequency as a cue signal for the predetermined short time period and thereafter erasing pre-recorded signals on the magnetic tape.

Cue signal recording circuit for magnetic recording and reproducing

A recording and reproducing apparatus for recording a carrier chrominance signal, comprises a separating circuit for separating a carrier chrominance signal from a color video signal, a recording signal processing circuit for converting the carrier chrominance signal into a carrier chrominance signal having a signal format suited for recording and reproduction, a recording circuit for recording an output signal of the recording signal processing circuit on a recording medium, a reproducing circuit for reproducing the recorded signal from the recording medium, a reproduced signal processing circuit for converting the reproduced signal from the reproducing circuit into a reproduced carrier chrominance signal having an original signal format, and a de-emphasis circuit responsive to the reproduced carrier chrominance signal from the reproduced signal processing circuit, for subjecting the reproduced carrier chrominance signal to a de-emphasis so that a high-frequency component in a vertical spatial frequency of the reproduced carrier chrominance signal is relatively attenuated compared to a low-frequency component of the reproduced carrier chrominance signal.

Recording and reproducing apparatus for recording and reproducing a

A multiplex recording and playback system records an audio signal into and plays it back from a track on which was stored a video signal. A rotary member, around which a magnetic tape is wound, carries therewith a plurality of video signal read and write rotary heads and a single audio signal read and write rotary head exclusively allocated to the audio signal and located ahead one of the video signal read and write heads by a predetermined angular distance. The audio signal read and write head has an azimuth angle which is sufficiently larger than those of the video signal read and write heads.

Sound and video multiplex recording system

A noise reducing system for a video signal, comprises a vertical pre-emphasis circuit supplied with an input video signal which is to be transmitted, for pre-emphasizing the input video signal and transmitting a pre-emphasized video signal to a transmitting system, and a vertical de-emphasis circuit supplied with a pre-emphasized video signal which is pre-emphasized by the vertical pre-emphasis circuit and is transmitted through the transmitting system, for de-emphasizing the pre-emphasized video signal. The vertical pre-emphasis circuit has a non-linear pre-emphasis characteristic for relatively emphasizing a high-frequency component of the input video signal in a vertical spatial frequency of a picture compared to a low-frequency component of the input video signal, with the degree of emphasis being reduced as the level of the input video signal increases. The vertical de-emphasis circuit has a non-linear de-emphasis characteristic for relatively attenuating a high-frequency component of the pre-emphasized video signal in a vertical spatial frequency of the picture compared to a low-frequency component of the pre-emphasized video signal, with the degree of attenuation being reduced as the level of the pre-emphasized video signal increases.

Noise reducing system for video signal

A noise reducing system for a video signal comprises a vertical pre-emphasis circuit supplied with an input video signal which is to be transmitted, for supplying an output signal to a transmission system, and a vertical de-emphasis circuit supplied with the video signal which has been pre-emphasized in the vertical pre-emphasis circuit and has been transmitted through the transmission system. The vertical pre-emphasis circuit has a characteristic for relatively emphasizing the level of high-frequency components of the input video signal having spatial frequencies in a vertical direction of a picture, compared to low-frequency components of the input video signal. On the other hand, the vertical de-emphasis circuit has a characteristic for relatively attenuating the level of the high-frequency components of the pre-emphasized video signal having spatial frequencies in the vertical direction of the picture, compared to the low-frequency components of the pre-emphasized video signal. The characteristics of the vertical pre-emphasis circuit and the vertical de-emphasis circuit cooperate so as to reduce noise having high spatial frequencies in the vertical direction of the picture.

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Chigasaki, Japan

Akira Hirota