| 摘要 |
PURPOSE:To simplify the reference signal write processing and improve the check precision by writing a reference position signal for position collation in a prescribed position of a track where a reference signal for check should be written (or is already written). CONSTITUTION:A prescribed frequency signal is written with a fixed time width Tb to write a reference position signal B a prescribed time Ta after detection of an index signal. Reference signals A1, A2, A3- for various checks are written in prescribed positions on a track 20, where the reference position signal B is written, as follows: rotation angles phi1, phi2, phi3- from the position of the signal B to write positions of reference signals A1, A2, A3- are specified preliminarily, and required times T1, T2, T3- from detection of the reference position signal B due to a magnetic head to write of individual reference signals are specified preliminarily in accordance with these rotation angles and a rotative velocity of disc 5, and the signal A1 is written the time T1 after the fall of the signal B, and signals A2, A3- are written similarly. |
