Patent ID: 8760785

Claim:
An apparatus comprising: circuitry configured to receive a waveform produced by a read head operated with respect to a recording medium, the medium comprising magnetic data positions, a first servo sync mark, a second servo sync mark, and phase tracking fields, wherein at least a portion of the phase tracking fields are arranged between the first servo sync mark and the second servo sync mark; circuitry configured to produce, based on the waveform, a servo detect pulse that indicates a detection of at least one of the servo sync marks; circuitry configured to control a first adjustment of a phase of a write clock signal, wherein the first adjustment is responsive to the servo detect pulse; circuitry configured to produce, based on the write clock signal, samples of the waveform that correspond to the phase tracking fields; and circuitry configured to control second adjustments of the phase of the write clock signal based on the samples to align the write clock signal with at least a portion of the data positions, wherein the second adjustments are responsive to the phase tracking fields, respectively.