A data storage device is disclosed comprising an actuator configured to actuate a head over a disk surface, and a vibration sensor configured to generate a vibration signal (VS). Control circuitry comprising a servo control system having a torque rejection curve (TRC) configured to control the actuator is configured to measure a position error signal (PES) of the head, and measure the VS output by the vibration sensor. A feed-forward compensator is configured based on PES/VS/TRC. While seeking the head across the disk surface, the VS is processed using the feed-forward compensator to generate a feed-forward compensation during a settle interval of the seek, and the actuator is controlled using the feed-forward compensation during the settle interval.

A recording device, a control device, a recording method, a recording tape cartridge, and a data recording and reproducing system capable of accurately positioning a data recording and reproducing head are obtained. A recording device includes a recording unit that records information on linearity of a servo signal recorded on a magnetic tape included in a recording tape cartridge on an RFID tag included in the recording tape cartridge.

Systems and methods are disclosed for phase locking multiple clocks of different frequencies. In certain embodiments, an apparatus may be configured to downsample a first clock having a first frequency and a second clock having a second frequency into downsampled clocks having the same frequency. The apparatus may adjust a frequency of the second clock so that the downsampled clocks are phase aligned. The apparatus may reset counters of the divider circuits that perform the downsampling so align them to a counter for the first clock. A counter for the second clock may also be reset to align with the counter for the first clock. The synchronized clocks may be applied in data storage operations, such as self-servo writing operations, where the first clock may be a read clock and the second clock may be a write clock.

According to one embodiment, a magnetic disk device includes a disk including a first region and a second region different from the first region, a head that writes data on the disk and reads data from the disk, an actuator that positions the head on the disk, and a controller which positions the head by driving the actuator and writes data in the first region and the second region with the head, a skew angle of the head with respect to a circumferential direction of the disk varying within a first angle in the first region, and varying, in the second region, from a second angle larger than the first angle to a third angle larger than the first angle and the second angle.

A recording device, a control device, a recording method, a recording tape cartridge, and a data recording and reproducing system capable of accurately positioning a data recording and reproducing head are obtained. A recording device includes a recording unit that records information on linearity of a servo signal recorded on a magnetic tape included in a recording tape cartridge on an RFID tag included in the recording tape cartridge.

According to one embodiment, there is provided a hard disk drive including a first recording surface, a second recording surface, a first magnetic head, a first actuator and a second actuator that move the first magnetic head, a second magnetic head, a third actuator and a fourth actuator that move the second magnetic head, a fifth actuator that moves the second actuator and the fourth actuator, a drive circuit that implements at least one of a first mode in which the second actuator and the fourth actuator operate differently from each other or a second mode in which the first and third actuators operate differently from each other, and a controller that controls the drive circuit.

According to one embodiment, a magnetic disk device includes a disk including a plurality of servo data items, a head including a write head which writes data to the disk, and a first read head and a second read head which read data from the disk, and a controller configured to position the head based on a first signal in which write data positioned between the servo data items of the disk is read by the first read head, and a second signal in which the write data is read by the second read head separated from the first read head in a radial direction of the disk.

A tape-type magnetic recording medium, includes a substrate; and a magnetic layer provided on the substrate. The magnetic recording medium is configured such that (1) (w.sub.maxw.sub.min)/w.sub.min400 [ppm] where w.sub.max and w.sub.min are respectively maximum and minimum of average values of width of the magnetic recording medium measured under four environments whose temperature and relative humidity are (10 C., 10%), (10 C., 80%), (29 C., 80%), and (45 C., 10%), respectively, and the magnetic layer has a squareness ratio of 65% or more in the vertical direction, and (2) 4.4T.sub.B/(T.sub.AT.sub.B) where T.sub.A is an average thickness of the magnetic recording medium and T.sub.B is an average thickness of the substrate.

An apparatus, according to one embodiment, includes a magnetic head having servo readers of known pitch, a drive mechanism for passing a magnetic recording tape over the magnetic head, and a controller electrically coupled to the magnetic head. The controller is configured to measure, using signals from the magnetic head, a servo band difference at various locations along a length of the magnetic recording tape. The controller is also configured to cause storage of servo band difference information about the servo band difference measurements in association with the magnetic recording tape.

A hard disk drive includes a disk having a servo region and data tracks. The servo region has servo data for formatting some of the data tracks for high capacity storage and others of the data tracks for low capacity storage. A head writes user data to the high capacity tracks in response to vibration less than a threshold value, and otherwise writes the user data to the low capacity tracks.