| 摘要 |
PURPOSE:To obtain easy to see character by a character generator displayed on the screen of a TV receiver especially at non-signal at preset and in a weak electric field by detecting a non-signal and a weak electric field so as to control the integration time constant of a horizontal synchronizing deflection circuit. CONSTITUTION:A horizontal synchronizing signal separated by a synchronizing separator circuit 6 is fed to a horizontal synchronizing deflection circuit 8 of horizontal synchronizing AFC and the circuit 8 controls the horizontal deflection of a deflection yoke 9. An integration circuit 12 of the circuit 8 is controlled by a detection output from a non-signal/weak electric field detection circuit 16 and the time constant of the circuit 8 is increased at non-signal and a weak electric field. Thus, the disturbance of the horizontal synchronization is controlled especially at the non-signal or weak electric field at preset and a character from a character generator displayed from a character generator character generating circuit 10 onto a color receiver 5 is legible without flicker.
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