| 摘要 |
PURPOSE:To prevent automatically the omission of a pulse by detecting the omission of an index pulse and controlling to raise the clamp level of a luminance signal each time said detected output occurs. CONSTITUTION:When the omission of an index pulse (a) occurs, the pulse (c) equivalent to the omitted pulse occurs. A monostalbe multivibrator 19 is operated by the input of the pulse and generates the high level output. For the level, a monostable multivibrator 19 is reset by a reset pulse (b) fed from a reset pulse forming circuit 12 and falls down to the low level. A staircase wave generation circuit 20 raises the level each time the high level is inputted. Namely, the level is raised to the 2nd level (E2)DELTAV higher than the first level (E1) with 1 high level input. The level is raised the 16th level sequentially. The output level lifts up the pedestal level of the luminance signal sequentially. |
