| 摘要 |
PURPOSE:To prevent a chroma noise production, to make complete the signal interrupting operation of a color killer circuit and to block the input of a residual leakage component to a color demodulation circuit, by attenuating the gain of the ACC amplifier at color killer, in a chroma signal processing circuit. CONSTITUTION:At the color killer operation, when the input signal 1 is at chroma signal, the gain of the ACC amplifier 2' is made zero with the color killer detection circuit 8. Thus, even at the black and white signal input without the burst signal, since the gain of the ACC amplifier 2' can be attenuated, without excessively increasing the video signal of black and white broadcast and charrier chrominance signal frequency band of noise, thus the signal interrupting operation for the color killer circuit can not be inactive. |
