| 摘要 |
PURPOSE:To obtain a negative/positive inverting circuit in common to the three systems of the NTSC, PAL and SECAM by applying a luminance signal for correcting white balance to a color difference signal from a demodulating circuit, and obtaining the color difference signal in response to the negative/positive inversion. CONSTITUTION:A chrominance carrier signal Sc separated at a separating circuit 12 is demoulated at demodulating circuits 13R, 13B and applied operating circuits 15R, 15B via LPFs 31R and 31B. A luminance signal DELTAY for correcting white balance is added at the operating circuits 15R, 15B and it is applied to negative/positive inversion switching circuits 32R, 32B. A switching signal SNP from a terminal 7 is applied to the negative/positive inverting switching circuits, and non-inverting signals, i.e., the color difference signals as they are obtained at the positive polarity and the phase of the color difference signals is inverted at the negative polarity. The color difference signal is supplied to the NTSC encoder 6 via LPFs 19R, 19B. |
