| 摘要 |
PURPOSE:To reduce an error in the number of tracks and to shorten a search time by measuring and detecting the scanning speed of a disk and calculating the number of tracks on the basis of the scanning speed. CONSTITUTION:Signal swhich are already recorded on the disk 1 are read out by pickups 5 in reproducing mechanisms 2-5, 21, 24, and 25 and demodulated by a demodulating circuit 7. A microcomputer 19 is supplied with signals from the reproducing mechanisms 2-5, 21, 24, and 25 and demodulating circuit 7 and generates and supplies control signals to servo circuits 17, 18, 20, and 22 to control operations of the reproducing mechanisms 2-5, 21, 24, and 25. A detecting means A controls the microcomputer to detect the scanning speed of the disk 1 which is reproduced by the reproducing mechanisms 2-5, 21, 24, and 25. A calculating means B calculates the number of conveyance tracks by using the scanning speed detected in fast searching operation and the microcomputer controls the reproducing mechanisms 2-5, 21, 24, and 25 so that the pickups in the reproducing mechanisms 2-5, 21, 24, and 25 are led by number of tracks. |
