| 摘要 |
PURPOSE:To execute the phase matching of a teletext signal and a sampling clock and to execute the secure receiving of teletext data by setting the delay quantity of a variable delay circuit so that error quantity data outputted from an error correcting circuit can be minimum. CONSTITUTION:Teletext data outputted from a flip-flop circuit 2 to execute the sampling of a teletext signal are supplied through an error correcting circuit 5 to a signal processing circuit and a control part 6 makes the delay quantity of a variable delay circuit 4 provided between a teletext signal sampling circuit 1 and the flip-flop circuit 2 variable per unit time. The delay quantity of the variable delay circuit 4 is set so that error quantity data outputted from the error correcting circuits 5 can be minimum. Thus, since a phase relation between a teletext signal A and a data sampling clock B is controlled so that the error quantity data of the error correcting circuit 5 can be minimum, the secure removing of the teletext data is always executed. |
