Nippon Hoso' Kyokai

Keiichi Yaguchi

Takeshi Yoshida

Yukio Kameyama

Hitoshi Masuko

In a magnetic video tape recording and reproducing apparatus (VTR) having rotary magnetic video heads rotating in a direction substantially perpendicular to the direction of tape travel, the width of the magnetic tape is reduced substantially to one inch from the conventional two inches, and eight video heads for recording a video signal on the magnetic tape and for reproducing the video signal from the magnetic tape are mounted on the circumferential surface of a rotary head drum having a diameter substantially equal to two inches and are arranged to be equidistant from one another in the direction of circumference of the rotary head drum. According to this invention, a compact VTR can be realized. In addition, the video signal may be transferred to and from the rotary head drum alternately through one of two circuit paths composed of a signal coupling means and an input/output circuit respectively, in order to realize a more compact, light weight and low power consumption VTR. Further, in order to improve the tape tracking accuracy in the case of such a narrow-width video head, use is made of a control signal whose n cycles of pulses in a pulse series obtained from a drum tachometer pulse are eliminated when a frame reference signal occurs so as to multiplex the pulse series with the frame reference signal. A control signal track is disposed at or around the minimum stretch portion or the center of the magnetic tape in the direction of the tape travel, and the tape travel is controlled by integral, differential, local proportional and proportional control systems, so as to further improve tape tracking accuracy.

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Tokyo, Japan

Keiichi Yaguchi