A hard disk drive desledder comprises a support and a cutting member. The support is configured to receive and to support a hard disk drive assembly that includes a hard disk drive and a sled. The cutting member has at least two cutting edges corresponding to respective portions of the sled. The cutting member is movable from a first position spaced apart from the support and a second position adjacent the support to cause the at least two cutting edges to cut portions of the sled to allow the hard disk drive to be removed from the hard disk drive assembly. Related desledding methods are also described.

A magnetic recording head includes a plurality of writers and at least one reader. The plurality of writers and the reader define a plurality of close points of the head. The plurality of writers are spaced apart from one another in a cross-track direction and positioned in the same plane of the head. A plurality of contact sensors are positioned proximate the plurality of writers and the reader. The contact sensors are coupled together and to a pair of electrical bond pads of the head and configured to sense for head-disk contact at each of the close points.

An apparatus comprises a spindle to rotate a magnetic recording medium and a magnetic field generator to expose a track of the medium to a DC magnetic field. The magnetic field generator is configured to saturate the track during an erase mode and reverse the DC magnetic field impinging the track during a writing mode. A laser arrangement heats the track during the erase mode and, during the writing mode, heats the track while the track is exposed to the reversed DC magnetic field so as to write a magnetic pattern thereon. A reader reads the magnetic pattern and generates a read signal. A processor is coupled to the reader and configured to determine an anisotropy parameter using the read signal. The apparatus can further comprise a Kerr sensor that generates a Kerr signal using the magnetic pattern.

An apparatus comprises a spindle to rotate a magnetic recording medium and a magnetic field generator to expose a track of the medium to a DC magnetic field. The magnetic field generator is configured to saturate the track during an erase mode and reverse the DC magnetic field impinging the track during a writing mode. A laser arrangement heats the track during the erase mode and, during the writing mode, heats the track while the track is exposed to the reversed DC magnetic field so as to write a magnetic pattern thereon. A reader reads the magnetic pattern and generates a read signal. A processor is coupled to the reader and configured to determine an anisotropy parameter using the read signal. The apparatus can further comprise a Kerr sensor that generates a Kerr signal using the magnetic pattern.

In one embodiment, a product includes a magnetic medium having written thereon data in a data track. The data includes encrypted data written over unencrypted data. An indicator of a physical position on the magnetic medium that corresponds to an end of the encrypted data is stored on the product. A product according to another embodiment includes a magnetic medium having written thereon data in a data track. The data includes encrypted data written over unencrypted data. A portion of the unencrypted data is located before the encrypted data on the medium. An indicator of a physical position on the magnetic medium that corresponds to a beginning of the encrypted data is stored on the product.

In one embodiment, a product includes a magnetic medium having written thereon data in a data track. The data includes encrypted data written over unencrypted data. An indicator of a physical position on the magnetic medium that corresponds to an end of the encrypted data is stored on the product. A product according to another embodiment includes a magnetic medium having written thereon data in a data track. The data includes encrypted data written over unencrypted data. A portion of the unencrypted data is located before the encrypted data on the medium. An indicator of a physical position on the magnetic medium that corresponds to a beginning of the encrypted data is stored on the product.

In an in-drive erase process in a single-surface HDD, erase spirals on the surface being erased can be employed to control writer position. A reader-to-writer timing offset value is determined for a plurality of radial locations on the surface to be erased, and an erase window is determined for a radial location disposed between two erase spirals. The erase window includes an erase start time, which is based on a spiral exit time of a reader and the reader-to-writer timing offset value for the radial location, and an erase stop time, which is based on a spiral encounter time of the reader and the reader-to-writer timing offset value. The erase window prevents complete erasure of erase spirals, so that the servo system of the HDD can continue to servo off of the erase spirals. The erase spirals may be written with a lower slope than conventional spiral tracks.

In an in-drive erase process in a single-surface HDD, erase spirals on the surface being erased can be employed to control writer position. A reader-to-writer timing offset value is determined for a plurality of radial locations on the surface to be erased, and an erase window is determined for a radial location disposed between two erase spirals. The erase window includes an erase start time, which is based on a spiral exit time of a reader and the reader-to-writer timing offset value for the radial location, and an erase stop time, which is based on a spiral encounter time of the reader and the reader-to-writer timing offset value. The erase window prevents complete erasure of erase spirals, so that the servo system of the HDD can continue to servo off of the erase spirals. The erase spirals may be written with a lower slope than conventional spiral tracks.

A magnetic recording head includes a plurality of writers and at least one reader. The plurality of writers and the reader define a plurality of close points of the head. The plurality of writers are spaced apart from one another in a cross-track direction and positioned in the same plane of the head. A plurality of contact sensors are positioned proximate the plurality of writers and the reader. The contact sensors are coupled together and to a pair of electrical bond pads of the head and configured to sense for head-disk contact at each of the close points.

In an embodiment, a storage device includes a shingled magnetic recording device, a management unit, selection unit, and execution unit. The shingled magnetic recording device performs writing in unit of a band including tracks being adjacent to and partially overlapping with each other. The management unit manages management information mutually associating band identifier of the band, characteristic information indicating a possibility that data stored in the band is not referred to, and data identifier of the data in a case where the data is stored in the band. The selection unit selects the band of the shingled magnetic recording device storing the data based on the data and the characteristic information in a case where the shingled magnetic recording device is requested to store the data. The execution unit stores the data to the selected band.