| 摘要 |
<p>PURPOSE:To exercise control over not only automatic recording and reproduction, but also interchangeable reproduction by eliminating the need for a control head by controlling a running speed on the basis of the reproduced sigal of an index signal recorded being superposed upon a video signal. CONSTITUTION:A phase comparing circuit 60 performs phase comparison between pulses S, synchronized with a signal DTP from a track head 3, and an index signalIand outputs a phase difference signal phi. The phase difference signal phi is supplied to a pulse shaping circuit 72, which outputs a pulse Q. Then, data D on a phase difference between the pulse S and pulse Q is written in the memory of a control circuit 71. After the writing to the memory, switches SW1 and SW2 are connected to the sides of terminals 1H and 2H respectively, and a pulse S2 generated by delaying the phase of the pulse S by the value of the data D is outputted from a delay circuit 70. On the basis of a phase difference signal phi between the pulse S2 and index signalI, a tape running speed is controlled.</p> |
