| 摘要 |
PURPOSE:To prevent the SN ratio from being lowered by the aperture compensating output, by raising the degree of amplification of a gain controlling circuit when a compensating signal exists in the video signal and lowering the degree of amplification of this circuit when the compensating signal does not exist in the video signal. CONSTITUTION:An input signal Es from a signal source is inputted to a signal delay line 31 through a resistance R1. The input and the output of this delay line 31 are sent to a differential amplifier 32, and a high-band component signal which is the difference signal and has a frequency characteristic for aperture compensation is supplied to a gain amplifier 39 in the next stage. The input Es from the signal source and the input signal to the signal delay line 31 are inputted to a differential amplifier 37, and the difference signal is inputted to a control signal generator 38. The gain of the amplifier 39 is controlled by the output of the generator 38, and the output of the amplifier 39 and the output of the delay line 31 are amplified differentially in a differential amplifier 34, thereby outputting an aperture-compensated signal Eo to a terminal 35. |
