| 摘要 |
PROBLEM TO BE SOLVED: To provide a color killer circuit that detects an amplitude of a burst signal even from the signal in a bad reception state resulting from superimposing a noise on a signal for a burst signal period so as to be capable of killer operation. SOLUTION: This killer circuit is provided with an absolute value circuit and with a killer ON/OFF discrimination circuit 2 (38c) that extracts a killer discrimination result for a burst period only from the absolute value circuit, a killer ON/OFF discrimination circuit 1 (38), a killer ON/OFF discrimination circuit 2 (38e) and OR circuits 38d, 38c, a color signal output interruption circuit 38a that conducts discrimination of killer ON/OFF depending on the quantity of the amplitude of a color demodulation output of a burst signal and applies ON/OFF of a color difference signal with an output of an integration circuit 38b so as to apply ON/OFF to a color demodulation output according to the killer ON/OFF discrimination result. Thus, on the occurrence of a noise for the burst period in a weak electric field with a bad reception state or even when a demodulation state is unstable to cause an offset of a demodulated phase, killer operation can be attained.
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