CONTROL METHOD OF MAGNETIC DISK HEAD

摘要

PURPOSE:To control the position of a magnetic head by using the alignment disks which are drawn concentrically with the data width in such a range that can be read by an erasion head to compare the reproduction outputs between erasion heads at the outer and inner circumferential sides. CONSTITUTION:The data are written concentrically and with high accuracy at the track positions that can be controlled within a range C which is larger than the shortest distance A and smaller than the longest distance B respectively between E gaps 2 and 3. These data are read at gaps 2 and 3 respectively. The reading data width is set at D an E at gaps 2 and 3 respectively. The output of a magnetic head is proportional to data widths D and E. Therefore the amplitude of the output waveform is set at D.alpha and E.alpha at the side of the gap 2 and the side of the gap 3 respectively. Then the center between gaps 2 and 3 is set at the center of the data to satisfy D=E. Therefore the head is fixed at a point where a waveform D.alpha=E.alpha is satisfied.