| 摘要 |
<p>PURPOSE:To eliminate the need of a band-pass filter, by triggering monostable multivibrators with pulse width having correspondence to respective synchronizing signal by the leading edge a reproduced output signal, latching the output signals of the monostable multivibrators, and detecting the synchronizing signals respectively by taking an AND with window pulses. CONSTITUTION:A waveform-arranged reproducing output signal reproduced at a limiter 32 triggers the monostable multivibrators 33 and 34 with at its leading edge. The monostable multivibrator 33 sends out an output signal with the pulse width having correspondence to the synchronizing signal. The output signal is latched by D flip-flops 35 and 36, and an erasing signal f4 is detected by taking the AND of the signal with the window pulse at an AND circuit 37, and the synchronizing signal SYNC2 is detected by taking the AND of the signal with the window pulse at an AND circuit 38, and the synchronizing signal SYNC1 is detected by taking the AND of the signal with the window pulse at an AND circuit 39. In such a way, it is possible to make the band-pass filter unnecessary, and to realize the miniaturization and the cost down of a device.</p> |
