Abstract: A method used to implement a sampled servo control system in a magnetic disk drive for generating a fractional track portion of a position error signal to correctably maintain the alignment of a read transducer (or associated write transducer) relative to a centerline of one of a plurality of a concentric data tracks upon a rotating data storage disk. The system uses a hybrid approach of determining a fractional track position by using a two-burst algorithm when possible and using a multi-burst algorithm only when necessary. The system is particularly suited to determining fraction track position when jogging a relatively narrow magnetoresistive read transducer with a servo pattern normally useful only for wider transducers, namely a pattern of four angularly sequential servo bursts A, B, C, D that are 100% of a track pitch in width and are arranged in quadrature.

Abstract: The invention relates generally to rotating magnetic storage disk drive and, more particularly, to a method of seamlessly recording circumferentially overlapping servo bursts on a magnetic disk with successive passes of a write head that is guided by a servo track writer wherein the servo bursts are contained in at least two servo burst groups that each have at least one circumferential burst position which may contain a servo burst.