Provided is a coating-type magnetic recording medium for microwave assisted recording. A magnetic recording medium for microwave assisted recording having a magnetic layer including ferromagnetic powder and a binder on a non-magnetic support, in which the magnetic layer exhibits an intrinsic ferromagnetic resonance frequency of 30.0 GHz or more. A magnetic recording device including the magnetic recording medium and a magnetic head for microwave assisted recording.

An apparatus having a memory and a controller is disclosed. The memory may have a write head and sectors in tracks. The controller may have a sector map and a translation map and may be configured to (i) receive a write command having a logical block address and a range value, (ii) examine the sector map to find a sector sequence (a) marked free, (b) about to reach the write head and (c) at least as long as the range value, (iii) write new data in the sector sequence, (iv) update the translation map to associate the logical block address of the write command with a physical address of the written sectors and (v) update the sector map according to the sectors written. Each entry in the sector map generally corresponds to a respective sector and indicates whether the respective sector contains valid data or is free.

An adjusting method for a magnetic disk device including a disk, a head that writes data on the disk, a controller circuit that outputs write data and a control signal related to the write data, and an integrated circuit that outputs a write current to the head, includes adding a delay to a timing of polarity inversion of one bit of the write data or the control signal, outputting the write data and the control signal added with the delay from the controller circuit to the integrated circuit, outputting from the integrated circuit to the head, the write current having a current value that is changed at one of timings of polarity inversion of the write data, according to the control signal, and adjusting a deviation between the write data and the control signal, based on the output write current.

An adjusting method for a magnetic disk device including a disk, a head that writes data on the disk, a controller circuit that outputs write data and a control signal related to the write data, and an integrated circuit that outputs a write current to the head, includes adding a delay to a timing of polarity inversion of one bit of the write data or the control signal, outputting the write data and the control signal added with the delay from the controller circuit to the integrated circuit, outputting from the integrated circuit to the head, the write current having a current value that is changed at one of timings of polarity inversion of the write data, according to the control signal, and adjusting a deviation between the write data and the control signal, based on the output write current.

A data writer may be constructed and operated as part of a data storage device. The data writer can be positioned proximal a data storage medium. The data writer may have a write pole positioned adjacent a writer coil with the writer coil having a plurality of turns. A controller that is connected to each turn can be adapted to selectively activate less than all the coil turns in response to the data writer being positioned over a first portion of a data storage medium and selectively activate all of the coil turns in response to the data writer being positioned over a second portion of the data storage medium.

A data writer may be constructed and operated as part of a data storage device. The data writer can be positioned proximal a data storage medium. The data writer may have a write pole positioned adjacent a writer coil with the writer coil having a plurality of turns. A controller that is connected to each turn can be adapted to selectively activate less than all the coil turns in response to the data writer being positioned over a first portion of a data storage medium and selectively activate all of the coil turns in response to the data writer being positioned over a second portion of the data storage medium.

A storage device includes a storage medium and a storage device controller that selectively varies a value of at least one write current parameter to generate alternating data tracks of variable written track width. According to one implementation, the alternating data tracks of variable written track width are generated with a single writer.

A storage device includes a storage medium and a storage device controller that selectively varies a value of at least one write current parameter to generate alternating data tracks of variable written track width. According to one implementation, the alternating data tracks of variable written track width are generated with a single writer.

A tape apparatus includes a tape drive and a processor. The tape drive is configured to perform data reading and data writing on a magnetic tape in which a plurality of tracks are formed. The processor is configured to control the tape drive to perform data reading and data writing on the plurality of tracks in a first segment among a plurality of segments obtained by dividing the magnetic tape in a running direction. The processor is configured to reserve a first track of the plurality of tracks as a copy target upon determining that an abnormality occurs in the first segment on the first track. The processor is configured to instruct the tape drive to copy data recorded in the first segment on the first track to a second segment on the first track at a predetermined timing. The second segment is adjacent to the first segment.

A tape apparatus includes a tape drive and a processor. The tape drive is configured to perform data reading and data writing on a magnetic tape in which a plurality of tracks are formed. The processor is configured to control the tape drive to perform data reading and data writing on the plurality of tracks in a first segment among a plurality of segments obtained by dividing the magnetic tape in a running direction. The processor is configured to reserve a first track of the plurality of tracks as a copy target upon determining that an abnormality occurs in the first segment on the first track. The processor is configured to instruct the tape drive to copy data recorded in the first segment on the first track to a second segment on the first track at a predetermined timing. The second segment is adjacent to the first segment.