| 摘要 |
PURPOSE:To prevent the lowering of the picture quality, by separating the chrominance signal from the luminance signal through just a single wide-band comb filter and accordingly simplifying the circuit constitution as well as eliminating the shift of both the delay time and the phase. CONSTITUTION:A composite video input signal IN containing the luminance and chrominance signals and extracted out of a recording medium is modulated to the frequency of a TV picture receiver through a modulating circuit 41 and by the modulated frequency given from an oscillating circuit 40. This modulated signal is added with a modulated signal which is delayed by a prescribed time by an ultrasonic solid state delay line 32 of a wide-band comb filter CF through an adder circuit 42 and at the same time receives a subtraction through a subtractor circuit 43 to be separated into the luminance and chrominance signals. On the other hand, the output of the circuit 42 is demodulated to a luminance signal band by a demodulating circuit 44 and then added with the output of the circuit 43 to be turned into an output signal. |
