Hitachi, Ltd.

Matsushita Electric Industrial Co., Ltd.

Hitachi Video Engineering, Incorporated

Hikaru Masui

Yoshizumi Watatani

Shigeyuki Itoh

Shinji Ozaki

Keiichi Komatsu

Norihide Kinugasa

Nobuo Azuma

Narutoshi Kanazawa

Osamu Takase

Toshiaki Ioi

Koichi Yoshimura

Yoshimitsu Saka

Ken Kubo

A video signal processing apparatus has a phase-locked loop which includes a quartz resonator, a voltage-controlled oscillator connected to the quartz resonator and oscillating at an oscillation frequency whose fundamental value is determined by the quartz resonator, and a horizontal sync signal lock circuit comparing a phase of a horizontal sync signal and a phase of an output signal from the voltage-controlled oscillator and controlling the oscillation frequency of the voltage-controlled oscillator in response to a difference between the phases of the horizontal sync signal and the output signal from the voltage-controlled oscillator. The video signal processing apparatus also has a device for modulating a video signal by use of the output signal from the voltage-controlled oscillator.

Video signal processing apparatus

Herein disclosed is a color video signal recording and reproducing apparatus for recording and reproducing a luminance signal as a frequency-modulated wave and a chrominance signal as a down-converted chrominance signal in and from a recording medium. The color video signal recording and reproducing apparatus comprises: a demodulator for demodulating the down-converted chrominance signal reproduced from the recording medium to generate color difference signals R-Y and B-Y in a base frequency band; a signal processor for reducing noises from those color difference signals; and a modulator for subjecting the carrier wave, which has a frequency equal to that of a color subcarrier of a color video signal, to a quadrature two-phade modulation with the color difference signals processed by the signal processor, to reproduce the chrominance signal.

Video signal recording and reproducing apparatus with signal processing

A pair of recording heads are mounted on a rotary cylinder for recording a video signal in slanted tracks on magnetic tape. The recording heads are mounted in a common plane and each has a different azimuthal angle. A pair of reading heads are mounted on the same rotary cylinder for reading the video signal recorded on the magnetic tape. The reading heads are mounted in a plane offset from the plane of the recording heads and have azimuthal angles that match the azimuthal angles of the recording heads. A mixing circuit mixes a component of the video signal ready from the magnetic tape by one of the recording heads with a video signal from a video signal source to generate a mixed video signal. The mixed video signal is returned to one of the recording heads for recordation on the magnetic tape.

Dual record/read head video recording and playback apparatus with

A magnetic recording and reproducing apparatus for eliminating the crosstalk component from an adjacent track of a tape of a VTR and obtaining a high picture quality. Chrominance signals in the base band which are produced by a low frequency conversion chroma signal are supplied to comb-shaped filters which are used in the magnetic recording and reproducing apparatus. The chrominance signals in the base band are obtained by generating carriers synchronized with a burst signal of the low frequency conversion chroma signal including the jitter component upon reproduction and by multiplying the carriers and the low frequency conversion chroma signal. A burst signal portion between the resultant chrominance signals in the base band is applied as a frequency control input signal to an oscillator as the carrier generating source, so that desired carriers are derived. Thus, the frequency fluctuation is eliminated from the converted chrominance signal in the base band and the high picture quality can be realized.

Chrominance signal reproducing apparatus for video tape recorder

An optical magnetic recording and reproducing apparatus and method including an optical beam scanner for scanning a recording medium with an optical beam and forming a track having a predetermined angle with respect to the traveling direction of the recording medium, a magnetic field applying arrangement for applying the magnetic field onto the recording medium, and optical beam generator for generating the optical beam.

Optical magnetic recording and reproducing method and apparatus capable

A tracking controlling device is provided which is suitable for a rotating head helical scanning-type magnetic video signal recording and reproducing apparatus in which pilot signals of a plurality of frequencies are recorded in advance on tracks on a magnetic tape such as to be superimposed on video signals, and the pilot signals are reproduced during reproduction so as to effect tracking control. This tracking controlling device comprises means for separating and detecting two reproducing pilot signals from both tracks adjacent to the track being scanned by the rotating head, a comparator for comparing the magnitude of the reproducing pilot signals from the adjacent tracks and for generating a binary PWM signal in accordance with the magnitude, and controlling means for controlling the rotation of a capstan motor for driving the magnetic tape using the tracking error signal converted into the form of the PWM signal obtained by the output of the comparator. The tracking error signal converted to the PWM signal is capable of directly switching over and controlling the driving circuit for the capstan motor.

Growing community of inventors

Ashiya, Japan

Hikaru Masui