| 摘要 |
PURPOSE:To permit continuous adjustment of an amplitude and a polarity of distorted signals with a potentiometer by providing a non-linear circuit outputting only for a period when video signal is either higher or lower than D.C. bias voltage, a differential amplification circuit outputting both in-phase and anti-phase signals and a potentiometer. CONSTITUTION:A video signal of a video input terminal 1 and bias voltage of a bias input terminal 2 are connected with each other after passing through respective diode 11 and resistance 12. If the video signal is outputted only for a period, when video signal voltage from an output terminal 3 of the non-linear circuit 10 is higher than bias voltage and is added to an input terminal 7 of a differential amplification circuits 20, anti-phase signal appears each other at output terminals 4 and 5. If their amplitudes are almost equal, the amplitude of the output signal which appears in a terminal 6 located at a middle part of a potentiometer 30 goes to 0, when the terminal 6 locates in a center of the potentiometer 30. And as its terminal 6 draws near either terminal 8 or 9, the amplitude becomes larger gradually due to the polarity of added signal. Thus a rotation of the potentiometer 30 between its both ends provides simultaneous adjustment of both the amplitude and polarity of the distorted signals.
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