| 摘要 |
<p>A helical scan video tape recorder having two rotary heads (6a,6b) mounted on a rotating drum (3) by electrically deflectable bi-morph leaves (7a,7b). To trace tracks on the tape (9) when the tape is played back at a speed different from that used for recording, tracking correction signals are repeatedly applied to the bi-morph leaves (7a,7b) to deflect the heads into position to trace the tracks (12) properly.
<??>Residual deflection in the bi-morph leaves (7a,7b), when the tracking correction signals terminate at the end of each trace, is removed by a hysteresis-erasing signal that flexes the bi-morph leaf back and forth. The polarity of the hysteresis-erasing signal depends on whether on playback the tape runs faster or slower than at recording. </p> |
