| 摘要 |
<p>PURPOSE:To detect tape running speed with high accuracy by providing fixed reproducing and recording heads by separating them by a prescribed distance, on the outside of a recording area by a rotary head, and detecting the tape running speed. CONSTITUTION:In an area outside of a recording area by rotary heads 3, 4 of a magnetic tape 1, a speed detecting square wave pulse is recorded by a fixed recording head 6, and also, by this pulse, a time detecting circuit 12 is started. Subsequently, a recording pulse is reproduced and applied by a fixed reproducing head being at a prescribed distance from the head 6, and the circuit 12 detects the running speed of the tape 1 from a distance between the heads 6, 7 and a reproducing signal time delay to a recording signal. By the constitution of the fixed head which does not use recording by the rotary head by which the level is varied frequently, the tape running speed can be detected stably with high accuracy.</p> |
