| 摘要 |
PURPOSE:To decrease the abnormal operation such as divergence and also residual distortion by providing always a required minimum value of leakage to a tap gain correcting control independently of the distorting state of an input signal. CONSTITUTION:A ghost component of a television set present at, e.g., input terminal 10 is eliminated by setting properly the tap gain of a transversal filter 20. The operation of correlation is attained by reading the content of an input waveform memory 41 and an error waveform memory 46 but the tap gain correcting control might be diverged because of the effect of the frequency characteristic of the transversal filter. If this divergence is not detected by an abnormal operation detecting circuit 63, its value is read from a tap gain memory 48, a leakage provision circuit 54 brings a main tape having the maximum tap gain to a predetermined value and provides leakage in the direction that the other tap is zeroed. When the divergence is detected, switches 60, 61 are changed over and the tap gain at divergence is reset by being shrinked proportionally. Then, the leakage amount is increased so as to prevent the divergence.
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