| 摘要 |
PURPOSE:To increase the quantity of recorded information without increasing the number of magnetic tracks, by recording control signals other than clock signals on the same track of already recorded clock signals under a superposed condition. CONSTITUTION:The section 3 of a magnetic medium is moved in the direction of the arrow 8. On the part 9 of the magnetic substance clock signals 6 are recorded for the whole section of the magnetic substance in the direction of thickness by a sufficiently large recording head current as shown by broken lines. When a control signal current which is different in kind from the clock signal is passed through a winding 12 at a value which is smaller than that when the clock signal is recorded, a residual magnetism 14 is kept only in a section close to the surface of the magnetic layer and the residual magnetism by the clock signal is kept under the same condition in the deep part of the magnetic layer. Therefore, two kinds of signals are recorded on the magnetic medium by forming two layers 14 and 9 in the direction of thickness. |
