| 摘要 |
PURPOSE:To prevent the disturbance of a picture due to a skew by controlling the switching of switches so that either a reproduced signal or a signal generated by delaying said signal for a prescribed time is selectively outputted to so that the horizontal cycles always continue at the time of switching various reproduction modes. CONSTITUTION:The switch 6 selects the reproduced signal form either head 4 or head 5. A delay circuit 8 delays a reproduced signal demodulated by a demodulation circuit 7 by 1/2H. A switch 9 selects either the demodulated signal or the 1/2H delayed signal. The switches 6 and 9 are controlled by a switch switching controller 11. The controller 11 consists of a T-FF 30' to invert its output at every trailing edge of PG pulse, a D-FF 31 to read a signal Sa from a system control part 13 at the timings of the PG pulses, a D-FF 32 that reads the signal Sb likewise and outputs a complementary signal, and a logic circuit. The control part 13 shifts the heads 4 and 5 by one-track length if a switch 12 is depressed to output the control signals Sa and Sb in a low level. Accordingly, the relation between the levels of a control signal to switches 6 and 9 and terminals to be connected is as shown in the table of the figure. As a result, at the time of switching various kinds of reproduction modes, the switches are switched so that the horizontal cycles are made always continuous with each other.
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