公开(公告)号：WO1992011542A1

公开(公告)日：1992-07-09

申请号：PCT/US1991009723

申请日：1991-12-20

Applicant: MAXTOR CORPORATION

Inventor： MAXTOR CORPORATION ,  HUBER, William, D. ,  SWANSON, Rod, J. ,  STARK, Dennis, C. ,  BUCSKA, Nicholas

IPC: G01R33/12

CPC classification number: G01R33/1207 ,  G11B20/1816 ,  H03D1/2245

Abstract: A media flaw detection apparatus having a sensitivity which is independent of the location of the flaw relative to the written test signal. The apparatus is equally sensitive to missing or extra bit defects. According to the invention, in-phase (14) and quadrature-phase (15) signals are heterodyned (16, 17) against the analog playback input signal. The resulting signals are squared (22, 23) and summed (24) to produce a signal analogous to the effect of the flaw.