Title:
WAVEFORM EQUALIZER
Document Type and Number:
Japanese Patent JPH02260876
Kind Code:
A
Abstract:
PURPOSE:To prevent a picture with no ringing or the like eliminated thereof from being displayed by discriminating whether or not asynchronous state of waveform equalization is caused tentatively when the waveform equalization is in the asynchronous state in the waveform equalization mode and continuing the waveform equalization mode when the state is tentative. CONSTITUTION:An RS flip-flop circuit 25 is provided between a phase locked loop PLL circuit 24 and a control circuit 21 and the RS flip-flop circuit 25 is used to detect whether or not the PLL circuit 24 is in the asynchronous state in the waveform equalization mode. In the case of the asynchronous state, the asynchronous time is measured and whether or not the result of measurement exceeds a predetermined asynchronous allowable time is discriminated and the waveform equalization mode is consecutive when the allowable time is not exceeded, and the waveform equalization mode is once released when the allowable time is exceeded and the waveform equalization is implemented again after the synchronizing state is recovered. When the asynchronous state is tentative, since the waveform equalization mode is consecutive as it is, a pattern including ringing or the like is not displayed different from the case of re-implementation of the waveform equalization.
Inventors:
SATOU ERI
NAKAMURA KAZUHIRO
NAKAMURA KAZUHIRO
Application Number:
JP7844289A
Publication Date:
October 23, 1990
Filing Date:
March 31, 1989
Export Citation:
Assignee:
TOSHIBA CORP
International Classes:
H04N5/21; H03H15/00; H04B3/04; (IPC1-7): H03H15/00; H04N5/21
Attorney, Agent or Firm:
Takehiko Suzue (3 outside)
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