| 摘要 |
PURPOSE:To obtain a DC component reproducing circuit which can completely be coincided the pedestal level, by sampling a part of the pedestal level of a video signal and subtracting the potential from the original video signal. CONSTITUTION:A video signal inputted from a terminal 36 is amplified at a transistor (TR) 31 and enters a differential operation amplifier 35 and an FET 32 through TRs 39, 40. On the other hand, a pulse for pedestal level sampling is applied to terminal 37 to operate the FET switch 32. The pedestal level sampled with the FET 32 is held at a capacitor 33 and an FET 34 and outputted from the source of the FET 34. The pedestal level held at the FET 34 enters the differential amplifier 35, where the subtraction with the original video signal is done and outputted as a video signal coincident with the pedestal level from a terminal 38. |
