DEVICE AND METHOD FOR ADJUSTING FILTER

摘要

PROBLEM TO BE SOLVED: To provide a filter capable of adjusting attenuation center frequency completely coincident with unnecessary frequency 4.84 MHz generated at the time of demodulating a chrominance signal converted at its low frequency. SOLUTION: The center attenuation frequency of a 4.84 MHz removing filter is controlled by DC voltage and deterioration of video quality is prevented by adjusting the center attenuation frequency of the 4.8 MHz removing filter which is completely coincident with unnecessary frequency 4.84 MHz generated at the time of demodulating the chrominance signal converted to its low frequency by using a specific adjusting signal.