Abstract: A magnetic disk device of embedded-servo type is capable of performing dummy operation for suppressing waveform degradation of signal reproduced by magnetic heads at a high speed with high reliability. When a waveform deformation occurs in a No.0 head, a controller changes over the No.0 head to a No.1 head operating normally, whereupon a cylinder portion for which dummy operation is to be performed is sought on the basis of the servo information supplied from the No.1 head. The cylinder portion destined for the dummy write operation contains servo information at timing positions that are the same for the individual magnetic heads. When passing of the No.1 head over the cylinder portion is confirmed, the No.1 head is changed over to the No.0 head for performing dummy write operation for suppressing the waveform deformation of the reproduce signal outputted from the No.0 head. Before the timing for succeeding information, the No.1 head is restored by issuing a head change command signal.

Abstract: A magnetic disk device of embedded-servo type is capable of performing dummy operation for suppressing waveform degradation of signal reproduced by magnetic heads at a high speed with high reliability. When a waveform deformation occurs in a No.0 head, a controller changes over the No.0 head to a No.1 head operating normally, whereupon a cylinder portion for which dummy operation is to be performed is sought on the basis of the servo information supplied from the No.1 head. The cylinder portion destined for the dummy write operation contains servo information at timing positions that are the same for the individual magnetic heads. When passing of the No.1 head over the cylinder portion is confirmed, the No.1 head is changed over to the No.0 head for performing dummy write operation for suppressing the waveform deformation of the reproduce signal outputted from the No.0 head. Before the timing for succeeding information, the No.1 head is restored-by issuing a head change command signal.

Abstract: A magnetic disk apparatus includes a dual head equipped with an MR head for reading data and an inductive head for writing the data. One ID portion and one servo pattern are disposed in one sector and an unequal track pitch is formed. The ID portion is formed at the center of a radius of two positions to which the MR head is positioned at the time of reading the data and writing the data, respectively.

Abstract: A favorable balance of mass and strength is provided by the truss type beam formed through the use of triangular apertures in the head arm, which further can be arranged to provide a greater leading edge beam strength than trailing edge beam strength. With increased density of data and correspondingly decreased flying height, favorable results are obtained by making the outermost yaw angle greater than the innermost yaw angle. Mass unbalance can be corrected by shifting the coil position.

Abstract: A head positioning system includes data head arms for supporting a data head, support head arms for supporting a support head, and a head actuator for rigidly moving the data and servo head arms as a unitary structure. When there is mounted an amplifier or the like is mounted on at least one of the head arms to change the warping amount depending upon the change in the environmental temperature, a portion of the head arm on which the amplifier is mounted is cut away therefrom but is left partly connected thereto, so that the head arms are all warped in nearly the same amount.