| 摘要 |
PURPOSE:To reduce the ringing of a reproduced low frequency conversion carrier chrominance signal due to mixed modulation distortion by employing a comb- line filter which filtrates a frequency component at least twice the chrominance subcarrier frequency of the low frequency conversion chrominance signal from an input low frequency conversion carrier signal. CONSTITUTION:The low frequency carrier conversion chrominance signal of the chrominance subcarrier frequency fS reproduced from a magnetic tape by a VTR is supplied to a delay circuit 11 and an adder 12 from an input terminal 10. The delay circuit 11 and the adder 12 comprise the comb-line filter 13. Its (adder 12) output signal turns out a signal where a frequency component of 2fS being a main component for ringing is emphasized. A subtractor 15 subtracts the output signal of a limiter 14 from the input reproduced low frequency carrier chrominance signal, whereby the reproduced low frequency conversion carrier chrominance signal from which a frequency component of 2fS (cross modulation distortion causing mainly ringing) is approximately off-set and removed is outputted to an output terminal 16.
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