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Publication numberWO2001075874 A3
Publication typeApplication
Application numberPCT/US2001/009557
Publication date3 Jan 2002
Filing date23 Mar 2001
Priority date30 Mar 2000
Also published asUS6430008, WO2001075874A2
Publication numberPCT/2001/9557, PCT/US/1/009557, PCT/US/1/09557, PCT/US/2001/009557, PCT/US/2001/09557, PCT/US1/009557, PCT/US1/09557, PCT/US1009557, PCT/US109557, PCT/US2001/009557, PCT/US2001/09557, PCT/US2001009557, PCT/US200109557, WO 0175874 A3, WO 0175874A3, WO 2001/075874 A3, WO 2001075874 A3, WO 2001075874A3, WO-A3-0175874, WO-A3-2001075874, WO0175874 A3, WO0175874A3, WO2001/075874A3, WO2001075874 A3, WO2001075874A3
InventorsSteven G Trabert, John P Mantey
ApplicantStorage Technology Corp
Export CitationBiBTeX, EndNote, RefMan
External Links: Patentscope, Espacenet
Measurement of tape position error
WO 2001075874 A3
Abstract
Positioning of a tape head relative to a magnetic tape may be improved through accurate measuring of magnetic tape position error. The tape head includes at least one read module having two servo read elements. A head control detects the presence of corresponding synchronization fields passing the servo read elements. The elapsed time between the detected synchronization fields is determined. Tape skew is calculated based on the elapsed time Tape position error calculation may be further improved by including another servo read element on either a second read module or a write module. Tracking information read from two servo read elements scanning the same servo stripe is used to calculate the offset between a read module and the write module.
Patent Citations
Cited PatentFiling datePublication dateApplicantTitle
EP0420374A2 *28 Feb 19903 Apr 1991Archive CorporationMethod to compensate for tape slope and head azimuth errors
US3678220 *26 May 197118 Jul 1972IbmAngulated positioning marks for moving web
US4258398 *12 Oct 197924 Mar 1981Eastman Kodak CompanyApparatus for preventing flutter and skew in electrical signals
US4392163 *16 Sep 19805 Jul 1983U.S. Philips CorporationMagnetic tape recording and/or reproducing apparatus with automatic head positioning
US4506309 *17 Dec 198219 Mar 1985Pericomp CorporationTape drive calibration meter
Classifications
International ClassificationG11B5/584
Cooperative ClassificationG11B5/584
European ClassificationG11B5/584
Legal Events
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3 Jan 2002DFPERequest for preliminary examination filed prior to expiration of 19th month from priority date (pct application filed before 20040101)
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