| 摘要 |
PURPOSE:To reduce rolling at the time of slow reproduction by correcting the speed of rotation of a rotary head cylinder by an output of a period measuring circuit. CONSTITUTION:At the time of slow reproduction by intermittent feeding, an output signal of the frequency generator PG5 of a cylinder motor 1 is inputted to a commanding circuit 20. When a capstan motor 11 is rotated synchronously with output signals of the PG5, it is fully accelerated until output signal frequency of FG 12 becomes a specified value. A speed system error signal is obtained by passing the output signal of FG 12 through a digital period measuring circuit 13 and a DA converting circuit 14, and the capstan motor is rotated at a fixed speed. While a magnetic tape is moved at a fixed speed, a control signal is detected from a controlling head 15, and the rotation is stopped. In the meantime, reproduction video signals are inputted to an input terminal 35, and inputted to a digital phase period measuring circuit 33, and the speed of rotation of the cylinder motor 1 is corrected.
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