According to an embodiment, a magnetic disk device includes a magnetic disk including a first storage area and a second storage area different from the first storage area. In the second storage area, both of a first post code that is used to write user data in the first storage area by a first method and a second post code that is used to write user data in the first storage area by a second method are stored in advance. The first method is a method in which one track between two tracks adjacent to each other overlaps a part of the other track between the two tracks. The second method is a method in which two adjacent tracks do not overlap each other.

A load/unload ramp assembly for a hard disk drive includes a support plate having at least one interlock slot and a plurality of ramp units interconnected with the support plate. At least one of the ramp units includes an interlock structure that protrudes into a corresponding interlock slot of the support plate, and is configured to move within the interlock slot in response to shrinkage of the ramp unit upon cooling associated with manufacturing of the ramp assembly. The ends of the interlock slot may be configured to manage the shrinkage and/or to maintain design dimensions.

According to one embodiment, a magnetic disk device includes a disk, a head including a main magnetic pole having a first end and a second end opposite to the first end in a radial direction of the disk, a write shield facing the main magnetic pole with a gap, and an assist element provided in the gap and at a position where a first distance between the first end and the assist element and a second distance between the second end and the assist element are different from each other, and a controller which controls a voltage applied to the assist element according to a shingled write direction in which a second track is overwritten on a first track.

Implementation of a non-interfering micro-positioning device, for a tape drive write/read head module assembly utilizing piezoelectric elements, by generating at least two flexure brackets. The at least two flexure brackets may include the piezoelectric elements. Affixing at least one flexure bracket to a first side of the write/read head module assembly. Affixing at least one other flexure bracket to a second side of the write/read head module assembly.

Implementation of a non-interfering micro-positioning device, for a tape drive write/read head module assembly utilizing piezoelectric elements, by generating at least two flexure brackets. The at least two flexure brackets may include the piezoelectric elements. Affixing at least one flexure bracket to a first side of the write/read head module assembly. Affixing at least one other flexure bracket to a second side of the write/read head module assembly.

According to one embodiment, a magnetic disk device includes a first actuator which actuates a magnetic head portion including a magnetic head, a second actuator which adjusts a position of the magnetic head on a magnetic disk in a radial direction of the magnetic disk, and a control portion which determines a second measurement signal amplitude when a second transfer function is measured in accordance with a first gain estimated value of the second actuator and an amplitude of a first measurement signal amplitude to the second actuator applied when a first transfer function is measured, which calculates a second gain estimated value of the second actuator based on the first transfer function and the second transfer function, and which updates the first gain estimated value, using the calculated second gain estimated value.

A method of operating a data storage device is disclosed comprising an enclosure comprising a first head actuated over a first disk surface and a second head actuated over a second disk surface. A manufacture printed circuit board (PCB) is coupled to the enclosure, wherein the manufacture PCB comprises at least one dual channel configured to execute concurrent access operations. While the manufacture PCB is coupled to the enclosure, the data storage device is operated as a dual channel device. The manufacture PCB is decoupled from the enclosure and a product PCB is coupled to the enclosure, wherein the product PCB comprises a single channel configured to execute a single access operation.

A methodology that enables, for example, tape drive operation at lower SNR and/or reduced rewrite area uses a first threshold T and a second threshold r for a rewrite condition. Codeword interleaves (CWIs) in a data set are written onto a plurality of simultaneously-written parallel tracks of a magnetic recording medium, read back and error correction decoded. A determination is made as to whether at least one of the C1 or C1 codewords in each decoded CWI contains more byte errors than the second threshold r of the rewrite condition. A number of CWIs in a rewrite buffer are according to the following criteria: b.sub.i=b.sub.iT when b.sub.i is greater than the first threshold T, and b.sub.i=0 when b.sub.i is less than or equal to the first threshold T.

A hard disk drive includes a first actuator and a second actuator. The first actuator is coupled to a first slider, which includes a first read transducer and a first write transducer. Both the first read transducer and the first write transducer are positioned away from a first longitudinal centerline of the first slider. The second actuator is coupled to a second slider, which includes a second read transducer and a second write transducer. Both the second read transducer and the second write transducer are positioned away from a second longitudinal centerline of the second slider.

A recording and reproducing apparatus includes: a magnetic head in which a servo band having a servo pattern and a data band having data tracks are alternately arranged along a width direction, the magnetic head including a recording and reproducing element that records or reproduces data with respect to the data track, and at least two servo reproducing elements that read servo patterns adjacent to each other in the width direction of the magnetic tape; a selection unit that selects a servo reproducing element from the servo reproducing elements according to a position of the data track, as a target of recording or reproducing of data in the data band, along the width direction; and a controller that controls positioning of the magnetic head along the width direction by using a result of reading of the servo patterns by the servo reproducing element selected by the selection unit.