AN IMPROVED METHOD FOR THE SECONDARY STANDARD REFERENCE SURFACE DEFINITION

Abstract

  A method is presented which allows for the nondestructive measurement of the new parameter KH50 which characterizes both the coercive force Hc and Mrt for magnetic disc. The technique involves the application of reference erasing magnetic field on previously written sequence of pulses with subsequent KH50 calculation which is the ratio of track average amplitudes (TAA) of readback pulses after and before erasing. Reference Disc specification by additional calibration factor KH50 allows for to define a Secondary Standard Reference Surfaces (SSRS) [1] with much closer to Standard Reference Surface (SRS) magnetic properties and therefore to increase magnetic disc performance measurement accuracy.