| 摘要 |
In a television receiver, a video amplifier circuit is provided all together witha means for varying both brightness, contrast and another means for varying contrast only. The former comprises a circuit for combining a video signal and a blanking pulse signal, a 1st transistor, a picture control circuit and a means for varying the amplification degree of an amplifier circuit; while the latter comprises a second transister for amplifying the video signal. The picture control circuit is connected to an emitter of the 1st transistor for controlling an a-c signal gain.
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