| 摘要 |
PURPOSE: To eliminate distortion in a reproduced picture at the cue and review modes by sampling a correcting error signal for capstan control at a prescribed position of scanning trace by a head at a high speed running state, holding the signal and controlling a capstan by this signal. CONSTITUTION:A monostable multivibrator 18 is triggered by the leading of a switching pulse (a) from a terminal 14, and a sampling pulse (b) is obtained. One head contacts a magnetic tape when the switching pulse (a) is at H and the other head contacts the magnetic tape when at L, and supposing that the scanning tracks C1, C3 are made by one head, and C2, C4 are made by the other head at the skew mode; an output of a differential amplifier 12 in frequencies f1, f2 of a pilot signal in the vicinity to the lower end of the scanning tracks C1, C3 is sampled by the sampling pulse (b) and this is held. Thus, the capstan speed is controlled so that the head reaches the track to be scanned in the vicinity of the lower end. The error near the lower end of the magnetic tape is held similarly at the review mode and the capstan is controlled. |
