A data storage device may have increased signal-to-noise ratio contact detection by employing a transducing head associated with a data storage medium each connected to a controller. The transducing head can have an alternating current heater excited to a first frequency for a first revolution of the data storage medium and to a different second frequency for a second revolution of the data storage medium. The second frequency may produce lateral transducing head motion as a result of physical contact of the transducing head with the data storage medium. The controller can issue a contact status in response to comparing a first plurality of position error signals logged during the first frequency to a second plurality of position error signals logged during the second frequency.

A data storage device can consist of a data storage medium that has a recording surface accessed by a first transducing head suspended by a first actuator and a second transducing head suspended by a second actuator. The first actuator may be configured to access a first region of the recording surface while the second actuator is configured to access a second region of the recording surface. The first and second regions can be separate and non-overlapping.

Systems and methods are disclosed for full utilization of a data path's dynamic range. In certain embodiments, an apparatus may comprise a circuit including a first filter to digitally filter and output a first signal, a second filter to digitally filter and output a second signal, a summing node, and a first adaptation circuit. The summing node combine the first signal and the second signal to generate a combined signal at a summing node output. The first adaptation circuit may be configured to receive the combined signal, and filter the first signal and the second signal to set a dynamic amplitude range of the combined signal at the summing node output by modifying a first coefficient of the first filter and a second coefficient of the second filter based on the combined signal.

According to one embodiment, a magnetic disk device includes a disk including two first servo sectors and at least a second servo sector, a head, and a controller, wherein the first servo sector includes burst data and a first data pattern written before the circumferential direction of the burst data, the second servo sector includes the burst data, the first data pattern, and a second data pattern written after the circumferential direction of the burst data, a first frequency of the first data pattern is different from a second frequency of the second data pattern, and a first length of the first data pattern is different from a second length of the second data pattern.

A method for characterizing a magnetic recording tape, according to one approach, includes measuring, using a magnetic head having servo readers of known pitch, a servo band difference at various locations along a length of a magnetic recording tape. The servo band difference measurements and/or derivatives thereof are stored in association with the magnetic recording tape. This procedure creates a characterization of the magnetic recording tape that is useful for assessing aging of the magnetic recording tape, as well as improving subsequent reading and/or writing operations.

Systems and methods are disclosed for phase locking of a clock. In some embodiments, a phase locked clock (PLC) module can phase-lock a write clock to a media written with multiple servo zones of different frequencies. In some implementations, this can be utilized to perform a self-servo write (SSW) of a disc surface within a hard disc drive (HDD). A PLC module can perform a method of writing with a single frequency phase coherently while a read element passes over servo zones with different frequencies. While the PLC module can perform such methods for a SSW process, the methods can also be utilized for other applications that can benefit from writing with a single frequency phase coherently based on servo zones with different frequencies.

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 for improving seek times in a read channel performing a read operation on a disk drive are disclosed. The method includes extrapolating, based on initial filter settings corresponding to a first user-data region or a first servo-data region and tracked settings varying over time, a proportionality constant for the programmable analog filter, in response to determining a new target frequency for the programmable analog filter corresponding to a second user-data region or a second servo-data region, computing new filter settings for the programmable analog filter based on the extrapolated proportionality constant, and transmitting, to the programmable analog filter, the computed new filter settings corresponding to the new target frequency of the second user-data region or the second servo-data region.

According to one embodiment, a magnetic disk device comprises a disk, a head that writes data to the disk and reads data from the disk, and a controller that controls a position of the head so as to write a first spiral servo pattern to the disk, and overwrite a second spiral servo pattern different from the first spiral servo pattern by shifting in a radial direction of the disk from the first spiral servo pattern.

A magnetic recording medium is provided and includes a substrate; and a magnetic layer provided over the substrate, wherein (wmax−wmin)/wmin≤400 [ppm] . . . (1) where wmax and wmin are respectively maximum and minimum of average values of width corresponding to samples of magnetic recording medium measured after the samples are stored for two hours under storage conditions (a loading tension in the longitudinal direction of the magnetic recording medium, a temperature and a relative humidity) for each of the samples, and a width of a sample of the magnetic recording medium at 25° C. and 50% relative humidity and without loading is ½ inch, magnetic recording medium has Young's modulus of less than 8.0 GPa in a longitudinal direction, and 4.0≤TB/(TA−TB) . . . (2) where TA is average thickness of magnetic recording medium and TB is average thickness of substrate.