| 摘要 |
<p>PURPOSE:To prevent the occurrence of a trace track deviation at mode shifting time by performing dynamic tracking control by means of a piezo-electric element in all double-speed reproducing modes. CONSTITUTION:When reproduction is started, a magnetic tape 4 is run and a rotary cylinder 6 is rotated by the rotation of a capstan motor 1 and a video head traces a recording track pattern A1. A piezo-electric element drive circuit 15 makes a video head 10 to oscillate perpendicularly to the track pattern by changing the state of a piezo-electric element 9. Thus the correcting output for obtaining the optimum tracing position at which the envelope of the reproduced output of the video head 10 becomes the maximum is given to the circuit 15.</p> |
