| 摘要 |
<p>PURPOSE:To suppress the deterioration of a piezoelectric element, and to obtain a stable reproducing output by making a difference between a voltage impressed to the piezoelectric element and a center potential minimum at the time of correcting the phase of the trace fields of first and second video heads. CONSTITUTION:A trace field phase correcter 13 adds and subtracts the voltage to displaces both video heads 10a for one track pitch to and from the output of an adding circuit 8, and outputs a correcting output to correct a trace position to an amplifier 15, based on the phase relation of the trace fields of both the video heads 10a. At that time, the phases of both the heads 10a are corrected so that the difference between the impressing voltage (center potential) when piezoelectric element 9a is not displaced to either positive or negative direction, and the voltage impressed to the piezoelectric element 9a, can be minimum. Thus, the deterioration of the piezoelectric element 9a can be suppressed, and the stable reproducing output can be obtained.</p> |
