| 摘要 |
PURPOSE:To detect pulse width even when a tape is fed without using a capstan motor, by comparing the output of a measuring means at the timing of the completing edge of a signal pulse with a shift output, and identifying two kinds of pulse width. CONSTITUTION:A reproducing control signal (CTL) synchronized with a clock (CK) is supplied further to a trailing edge detection circuit 37, and the completing edge of a pulse is detected. The output is supplied to a flip-flop circuit 38 as a sampling pulse, and at the detecting timing of a trailing edge, the Q output of a flip-flop circuit 35 is read in the flip-flop circuit 38. In this case, a counted value at the timing of the completing edge of the pulse is larger than the shift output if the pulse width is larger than a half cycle, and the counted value is smaller than the shift output if it is smaller than the half cycle. Therefore, by comparing the counted value at the timing of the completing edge of the pulse with the shift output, it is possible to identify the pulse width.
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