| 摘要 |
PURPOSE:To reduce the occurrence of beat interference due to crosstalking, by shifting the carrier frequency of the adjacent track of FM video signals recorded on a disk for odd number times of the half of the horizontal scanning frequency fH. CONSTITUTION:Sound signals from sound signal sources 11 and 12 are modulated by frequency modulators 13 and 14 and supplied to a mixer 15. Color video signals from a color video signal source 16 are divided into the luminance component and the chromaticity component by comb line filters 17 and 18. The chromaticity component is low-area converted by a chrominance component converting circuit 21 and mixed with sound signals after it is mixed with the luminance component and subjected to the pre-emphasis. A carrier shifting circuit 27 gives carriers which are shifted for odd number times of fH/2 between adjacent tracks by a switching pulse from a reference pulse generating circuit 26, to a frequency modulator 25 and FM modulates the output of a mixer 15. When the FM modulated carriers are recorded on a disk, occurrence of beat interference due to crosstalks between adjacent tracks is minimized. |
