Measurement of head fringing field effects on optimum gap width and position error performance

The magnitude, direction, and gradient of the side fringing gap field, along with the recording media magnetic characteristics, determines the optimum gap width for a given track center spacing and also the position error sensitivity of a head. An effective way of determining this optimum gap width is to measure and appropriately analyze the spectral components of both the desired signals and unwanted interference and noise using test heads and media as much like the final system design as possible except for head width, head to media velocity, and channel bandwidth.