| 摘要 |
PURPOSE:To reduce clamp circuits to the minimum of necessity, to decrease the errors which occur by the difference of the deviation of a reference electric potential or a temperature characteristic, and to simplify the circuit for the temperature characteristic compensation by constituting so as to use the clamp circuit used at the time of record and the clamp circuit used at the time of reproduction in common. CONSTITUTION:At the time of recording, color difference signals R-Y and B-Y from input terminals 1 and 2 are selected by switching switches 19 and 20, transmitted to clamp circuits 3 and 4 and after they are clamped, blanking operation is executed to them by the contact points a1, a2 and b1, b2 of changeover switches 21 and 22. At the time of reproduction a line sequential color difference signal 8 reproduced from a record/reproduction part 7 and a line sequential color difference signal 9 delayed in one horizontal scanning period are selected by the changeover switches 19 and 20, transmitted to the clamp circuits 3 and 4, and the line sequential signals are clamped, as the color difference signals R-Y and B-Y are selected at every horizontal scanning period by the contact points a1, a2 and b1, b2 of the changeover switches 21 and 22 and transmitted to an output part 18, the level in a blanking period is set by contact points a3 and b3 of the changeover switches 21 and 22.
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