| 摘要 |
PURPOSE:To increase the resolution of vertical direction, by changing the characteristics of the luminance signal pick up filter in response to the charrier chrominance signal level, in separating the luminance signal interleaving and the carrier chrominance signal. CONSTITUTION:The video signal Sa reproduced via the heads 15A, 15B, reproducing amplifier 41, limiter 42, and FM demodulator 43, is fed to the subtractor 61 via the delay circuit 44 by the Y-type comb type filter or directly, being the carrier chrominance signal Sc and further, converted into the carrier chrominance signal Ss via the band pass filter 63 and the frequency converter 62. The signal Sc is directly or via the envelope detector 54 fed to the multiplication circuit 53 as the level controller. The carrier chrominance signal in the video signal Sa has opposite polarity as the output signal of the multiplication circuit 53, and the adder 51 inputting the both signals outputs the luminance signal Sy. The signal Sy via the de-emphasis circuit 57 and the signal Ss are fed to the adder 45 to be reproducing video signal. The AFC circuit 71 and APC circuit 80 correct the time axis error of the signal Ss. |
