Studies of the "magnetizing region" of a ring-type recording head

The region within which a recording head changes the magnetization state of adjacent recording media was investigated for a 142 μm gap-length ring-head using a dc-pulse recording technique, with varying head-to-tape spacing up to 965 μm. For longitudinal easy-axis recording media, the ,"magnetizing region" has an approximately circular cross-section, with the radius proportional to current amplitude, and inversely proportional to media coercive force. Signal amplitude, read in contact from different "sublayers", decreased with increased record head-to-tape spacing, and with decreasing angle between the boundary of the magnetizing region and the surface of the recording media. Magnetic spacing material containing γ-Fe2O3particles caused a small increase in the radius of the cross-section of the "magnetizing region", but had little effect on signal amplitude for dc-pulse signals. For isotropic recording media, the configuration of the "magnetizing region" is modified by the combined effect of in-plane and perpendicular head field components.