| 摘要 |
PURPOSE:To read out stably a servo signal by forming a magnetic recording disk drilling precisely a disk fixing center hole into the center position of a servo signal track, and consisting of a floppy disk free from eccentricity. CONSTITUTION:A servo signal track 2 recording a head positioning servo signal and a reference signal track arranged concentrically with the former track 2 and recording a track center positioning reference signal are simultaneously formed. A recording medium sheet 1 is arranged on a sheet operating board for a press working means 5 having a magnetic reproducing and detecting means obtained by embedding plural magnetic conversion heads 7a-7d on a circumference having the same diameter as the reference signal track so as to be located on a position allowed to reproduce and detect a signal in the reference signal track on the sheet by the magnetic reproducing and detecting means on the sheet operating board. The fixing center hole is drilled into the center position of the servo signal track on the recording medium sheet by the press working means. Since the sheet is formed on the disk concentric with the servo signal track, the fixing center hole can be drilled into the center position of the servo signal track. |
