Patent ID: 6430008
Filing Date: 2002-08-06
Classification: G11B

Abstract:
A system for measuring position error of a magnetic tape, the magnetic tape having a plurality of data tracks and a plurality of servo stripes across the tape width, each servo stripe of the plurality of servo stripes having a periodically spaced sequence of synchronization fields and tracking patterns, each particular synchronization field of the plurality of synchronization fields in any servo stripe aligned across the width of the tape with a corresponding synchronization field in any other servo stripe of the plurality of servo stripes, the system comprising:a multiple module tape head comprising at least one read module and at least one write module for accessing the magnetic tape moving at a tape speed in a tape direction past the tape head, each write module of the at least one write module comprising at least one write element for writing data on the magnetic tape and the at least one read module comprising at least two servo read elements operative to detect the synchronization fields; and a head control in communication with a first servo read element on the at least one read module and a second servo read element on the at least one read module located a fixed distance from the first read element, the head control operative to (a) detect the presence of one of the particular synchronization fields passing the first servo read element, (b) detect the presence of the corresponding synchronization field passing the second servo read element, (c) determine an elapsed time between the detected particular synchronization field and the corresponding synchronization field, and (d) determine tape skew based on the determined elapsed time, the fixed distance between the first servo read element and the second servo read element, and the tape speed.