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Head/Disk Assembly Tester Autocalibrator Disclosure Number: IPCOM000042027D
Original Publication Date: 1984-Mar-01
Included in the Prior Art Database: 2005-Feb-03

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Related People

Davenport, JS Laczko, L [+details]


In the manufacture of disk files, the magnetic disks are subjected to a surface analysis test to insure that the storage characteristics of the disk meet predetermined specifications. One such test involves comparing the amplitude of the read signal from data stored on a disk with a reference voltage, called clip level. The clip level signal is generated by a digital-to-analog converter (DAC) which is controlled to provide a signal that a known percentage of the nominal signal amplitude expected. The compare test is a go/no-go type test. In order to insure that the tester is operating according to specifications, a "standard" disk surface is tested and the tester is recalibrated. These calibration runs are costly and complex.