公开(公告)号：FR2375688A1

公开(公告)日：1978-07-21

申请号：FR7734665

申请日：1977-11-10

Applicant: IBM

Inventor： COMMANDER ROBERT D ,  GARDNER PETER A

IPC: G05D3/12 ,  G11B5/596 ,  G11B21/10 ,  G11B5/02

Abstract: A data storage apparatus, such as an accessing head magnetic disk file, includes at least one data disk surface and a servo disk surface. In operation, a continuous position signal having high frequency components is derived from the servo surface, which has a quadature type servo signal prerecorded thereon. A circuit means modifies the derived position signal so that a substantially linear signal representing the displacement of the servo head from the servo track is obtained. A second position signal having a low frequency component is obtained from servo sector information registered on the data disk surface and together with the first position signal forms a hybrid position signal. This hybrid signal is used to control the movement of the data heads relative to the data tracks to ensure optimum transducing operation.

公开(公告)号：FR2294509A2

公开(公告)日：1976-07-09

申请号：FR7532213

申请日：1975-10-13

Applicant: IBM

Inventor： GARDNER PETER A

IPC: G11B21/10 ,  G11B21/02 ,  G11B21/00