Embodiments of the present invention enables the trimming and writing of
servo bursts in a null burst servo pattern as multiple portions in
multiple passes while still demodulating each of the servo bursts as a
single burst to obtain PES. Alternatively, the servo bursts can be
trimmed and written using different currents in different passes
respectively so that a gap can be created in the radial direction between
the servo bursts. This description is not intended to be a complete
description of, or limit the scope of, the invention. Other features,
aspects, and objects of the invention can be obtained from a review of
the specification, the figures, and the claims.