| 摘要 |
PURPOSE:To apply winding torque corresponding to a tape speed to a reel by integrating the DC voltage corresponding to the duty ratio of the pulse of a frequency generated correspondingly to the tape speed, adding the prescribed DC voltage thereto, and driving the reel motor. CONSTITUTION:A magnetic tape 1 is taken up by a takeup reel 2, and a reel base 3 is rotatably coupled to a reel motor 4. A capstan motor 7 and a frequency generator 8 are coupled directly to a capstan 5, thereby producing a signal Sa proportional to the rotating speed. A pulse Pb shaped by a shaper 11 is supplied to a capstan servo circuit 12, is supplied to a monostable multivibrator 14, and is added in voltage by transistor Q5, Q6 through the integrator 15 of a resistor R11 and a capacitor C2, thereby driving the motor 4. The output of the multivibrator 14 is zero at the time of reproducing a reference by a system control circuit 13 to provide the prescribed torque, and a takeup torque corresponding to the tape speed is provided at the time of shifting the speed in positive direction, and the torque can be increased at the time of reproducing in reverse direction. |
