| 摘要 |
PURPOSE:To prevent a mechanical system including a video head from resonating by applying a signal from a driving signal generator between electrodes of a transducer via a current limiting resistor and by specifying the relation of the resistance value. CONSTITUTION:The output signal of driving signal generator 20 is applied between electrodes of piezoelectric element 1, provided with video rotary magnetic head 2 of an auto tracking device, via current limiting resistance 6. When the inter-electrode capacity of piezoelectric element 1 is denoted as Co and the value of resistance 6 as R, value 2piXC0XR is set much less than the fundamental repetitive period of a driving signal and nearly equal to the resonance period of the mechanical system including piezoelectric element 1 and magnetic head 2. Accordingly, by providing resistance R, the resonance of the mechanical system is prevented from being retained and ringings are reduced effectively at the mechanical resonance frequency. |
