Multitransducer head positioning servo for use in a bi-directional magnetic tape system
US5121270A · kind A · utility
Inventors
Key dates
| Filing date | Sep 19, 1989 |
| Grant date | Jun 9, 1992 |
| Priority date | — |
| Expiry date | Sep 19, 2009 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B5/5508
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
In a multichannel recording/playback apparatus, a bi-directional transport longitudinally moves a magnetic tape past a multitransducer magnetic head for recording and/or playback. The magnetic head is positionable to selected tracks in a stepwise manner across the width of the tape. A head positioning servo utilizes binary patterns pre-recorded on the tape, consisting of magnetized blocks and non magnetized blocks which are read by a servo transducer integral with the multitransducer head stack. For each centerline corresponding to a specified track location, the servo tranducer straddles the line between adjacent, longitudinally recorded patterns and when the servo transducer is "on track" two conditions are met: 1) the played back code is the track address included in the track location identifier stored in a controlling microcontroller, 2) the amplitudes of the "1 bits" of the played back code are all the same and equal to 1/2 the amplitude of a full track width output. When "on track", the servo transducer straddles the line between adjacent lines of magnetized blocks and non magnetized blocks, and therefore plays back 1/2 amplitude signals from the magnetized blocks on one sid…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.