| 摘要 |
PURPOSE:To reduce the color noise, by fetching the video signals darker than the set level, supplying the output signal to a terminal that controls the amplification factor of the color density and controlling the amplification of color density in accordance with the brightness. CONSTITUTION:The signal output received the video wave detection is connected to an input terminal 5A of a control circuit 5, and the circuit 5 is connected to a color demodulating circuit 7. The video signal applied to an input terminal 13 of a comparison/detection circuit 11 is compared with the level set within the circuit 11, and only the signals darker than this set level are detected. The next level shifting circuit 12 functions to give the DC level shift to the detected signal, and this output signal is applied to a color density control terminal 5B of the circuit 5. Thus the amplification factor of the color density is controlled in accordance with the brightness of the signal. |
