| 摘要 |
PURPOSE:To eliminate the occurrence of a flicker on a screen by a waveform process to coincide the level of a video signal in a reproducing signal that is delayed with the level of the video signal in the reproducing signal that is not delayed without receiving the influence by temperature and the like. CONSTITUTION:The peak level of the video signal in the reproducing signal that is delayed by H/2 at a delay circuit 25 and the peak level of the video signal in the reproducing signal that is not delayed are inputted respectively to the input terminals of a pair of operational amplifiers 29 and 30 which are easy to be balanced and also, the output of each operational amplifier is inputted to a differential amplifire 31 and an error voltage is obtained byh comparing those. Based upon the error voltage, these are coincided with the level of the video signal of both signals and also the pedestal levels of both reproducing signals are coincided by a pedestal level circuit 37 and furthermore, the sync chip levels of both reproducing signals are fixed at a fixed potential by an NPN transistor Tr 3. Thus, the composite video signal from which possibility of occurrence of flickering by the flicker is eliminated is obtained.
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