A data storage device testing system may be configured with at least a test slot, a loader assembly, and an exchange assembly. The loader assembly can be positioned to respectively engage and disengage a test deck with the test slot. The exchange assembly may be configured to open an access port portion of the test deck and subsequently replace a tested data storage component housed within the first test deck with an untested data storage component.

A method and apparatus for detecting tightness of a pick-up head, and a method and apparatus for controlling the moving of the pick-up head are disclosed. The method for detecting the tightness of the pick-up head includes moving the pick-up head to an inner area of the disc reading device when then disc reading device is powered on, moving the pick-up head to an outer area of the disc reading device within a predetermined time period, moving the pick-up head from the outer area of the disc reading device to the inner area at a constant speed by a first fixed force, and recording the moving duration for moving the pick-up head from the outer area of the disc reading device to the inner area at the constant speed.

Systems and methods are disclosed relating to electro-mechanical devices and related computer control and audio processing systems intended to optimize playback fidelity of phonograph records. Said recordings are manufactured by a process that employs a cutting head assembly driven in a straight path from the outer to the inner-most radius of the recordable surface. However, most record turntables device that are used to play back phonograph records rely on a stylus transducer attached to the end of a pivoting arm. Instead of the linear path followed by the original cutting head, said tonearm traces an arc across the surface of the recorded disk resulting in playback distortion proportional to error in alignment of said stylus relative to the tangent of the groove. This invention addresses this deficiency and produces an optimal audio quality of playback of phonograph records.

According to a magnetic disk apparatus of one embodiment, threshold voltages of memory cell transistors of a flash memory are set to a first section for a first value or to a second section for a second value. The second section is on a lower voltage side than the first section. The controller performs bit inversion of second data held in a volatile memory and writes the second data onto the flash memory when a power loss occurs while the second data corresponds to third data in which a number of the first values is larger than that of the second values. The controller writes the second data onto the flash memory without bit inversion when a power loss occurs while the second data corresponds to fourth data. The fourth data is data in which a number of the first values is smaller than that of the second values.