摘要 |
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. |