| 摘要 |
<p>PURPOSE:To discriminate the recording tape speed in the intermittent slow reproduction mode by setting a frequency partly different during the period of a frequency injecting pilot signal corresponding to a reproduced track at the tap halt state so as to generate a phase lock signal thereby detecting the fluctuation period of the phase lock signal. CONSTITUTION:An injected pilot signal generating circuit 7 revises a frequency of the sequence next to the frequency of an injected pilot signal in the sample timing of a 2nd sample-and-hold circuit 15 in a field of the injected pilot signal of the frequency the same as that of the pilot signal of a track reproduced in the still reproduction. A phase lock signal 17 is a prescribed level output in applying intermittent slow reproduction in the mode of the tape speed the same as that at the recording and is fluctuated periodically in the intermittent slow reproduction in the mode of the different speed. Then a microcomputer 19 detects the fluctuation to discriminate the recording tape speed.</p> |
