| 摘要 |
<p>PURPOSE:To surely detect a synchronizing signal by adding a continuous Hi detecting circuit and a continuous Lo detecting circuit to a synchronizing signal detecting circuit and switching the continuous detection time width by the cycle of the recorded synchronizing signal. CONSTITUTION:When the Hi and Lo sections of the output of a comparator 13 are measured by the 1st and 2nd counters 16 and 17 respectively, the counting start and end time points of both counters 16 and 17 are controlled by the detection outputs of both a continuous Hi detecting circuit 14 and a continuous Lo detecting circuit 15. In other words, the continuous detection time values of both circuits 14 and 15 are set at the levels accordant with the cycle of each synchronizing signal with the output of a head switch signal generating circuit 20 even when the synchronizing signals recorded via the reproduced tracks are different from each other. Thus the detecting ability is improved for the synchronizing signal. As a result, the synchronizing signal is surely detected even at reproduction of a magnetic tape having a low grade of the synchronizing signal to be reproduced. Thus a magnetic tape can be stably reproduced.</p> |
