象磁鼓和磁带一类的转动存贮装置,表面速度是相当高的,为了防止表面磁层的损耗,通常使磁头离开旋转体(磁鼓或磁带)表面一个微小的间隙。这个间隙越小越好,否则磁记录密度将大大降低,同时希望这个间隙在运转过程中保持不变,这样信息才会均匀,读出电压幅度才会不变。 Rotating storage devices, such as drums and magnetic tapes, have relatively high surface velocities. To prevent loss of the surface magnetic layer, the magnetic head is normally removed from the surface of the rotating body (drum or tape) by a slight amount. The smaller the gap the better, or magnetic recording density will be greatly reduced at the same time I hope this gap remain unchanged during operation, so that information will be uniform, read the voltage amplitude will not change.