Abstract: A method for monitoring the alignment of the read-write head of a magnetic media data storage device comprising the steps of: establishing an elasped time window during which the read-write head should pass through a predetermined position if the head alignment has not drifted; checking to determine if the actual time at which the read-write head passes through said position actually falls within said window; and providing a pair of signals for indication of alignment or misalignment.

Abstract: A standardized, calibrated drop-out disk is provided to test disk certification equipment. The disk is a previously certified high quality disk having one or more selected tracks thereon upon which data is recorded at a standard level over some portions of the track and at differing levels on other portions of the track known as drop-out portions. The magnitude and playback amplitude of the drop-out portions is selected to be less than that of the remaining portions of the track. Methods of creating the standardized drop-out disk utilizing either varying write currents delivered to the head for the different portions of the track and/or write heads of different width being utilized are also provided. The standardized drop-out disks are utilized to test the sensitivity and accuracy of disk certification equipment as it is used to test production of magnetic disks.