| 摘要 |
PURPOSE:To smoothly perform the switching of the driving direction of reel motors between the normal and reverse directions, by interrupting the control signal only for a prescribed period when the tape running is switched from one mode of either normal or reverse fast forwarding mode to the other, and, at the same time, by applying the driving signal whose level is lower than a fixed level to the supply reel side. CONSTITUTION:When the fast forwarding mode is switched to the rewinding mode, the charging time constant of a time constant circuit 18 becomes extremely small, and, since the discharging time constant of another time constant circuit 19 is selected to a relatively large level, an MMV16 is triggered and its output becomes a single-shot pulse which is high in level for a fixed period. Since a servo control signal which is the output of frequency/voltage converters 8 and 9 is interrupted during the period, a driving motor 4 of a winding reel 2 is driven by a high level reference voltage E1. Moreover, the damping output of the time constant circuit 19 is applied to a driving motor 5 of a feeding reel 3 for a fixed period. Therefore, tapes will not be slacked and damaged, and no extensive delay will take place at the time of switching. |
