| 摘要 |
PURPOSE:To stabilize a synchronous separation operation and to promote the amplitude enlargement of a burst signal for recording and the improvement of an S/N ratio by providing an attenuation means to attenuate only the burst signal among reproducing video signals and separating horizontal synchronous signals after passing the reproducing video signals through the attenuation means. CONSTITUTION:Reproducing luminance signal Y is inputted in an input terminal 30 and the burst signal is removed by an LPF 20 as a burst signal attenuation means. And the horizontal synchronous signal is separated through a synchronous separation circuit 3 and the tip of the horizontal synchronous signal is clamped up to a specified voltage in a clamp circuit 19. In addition, a reproduced DC-wise Y signal inserted by the burst signal after reproducing DC-wise is added to a level 31 and burst gate circuits 5. On the other hand, a burst flag signal is produced by a burst flag generation circuits 4 and the burst signals are separated through a burst gate circuit 5 and also at the portion of a level shift 31, a level shifter allows the removal of the burst signals inserted in a back porch and back porch levels to be shifted and to be returned to an initial level. Thus respective initial signals Y, burst signals, horizontal synchronous signals are outputted to output terminals 32 and 34.
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