摘要 |
A comb filter circuit (1) with a usual comb filter (3) contains a circuit to detect line-parallel color edges. To that effect, envelope curves (Sf2, Sf3) are created from the addition signal (Sb) and the subtraction signal (Sc) of the delayed and the undelayed color signal (Si) on the input side of envelope curve demodulators (23, 15), and a control signal (St) is created in a comparator circuit (38) by comparing the envelope curves, which adjusts the signal portions of the transmitted and delayed color signal on the input side, and transmits them with an adjustable electronic fader control (40) to the signal output (29) of the comb filter circuit. To ensure trouble-free control even under operating conditions, during which a large portion of cross talk signals are scanned, an additional comb filter (31) is connected to the signal path of the subtraction signal (Sc), which eliminates most of the cross talk portions on this signal path.
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