A disk drive has a sampled servo system controller and a disk. The disk has a
plurality
a plurality servo burst fields, the plurality of servo burst field including first
and second normal burst fields, and first and second quadrature burst fields. A
portion of the first quadrature burst field is circumferentially contiguous with
the first normal burst field and spans a portion of a radial extent of the first
normal burst field. The second normal burst field is radially aligned with and
away from the first normal burst field and spans a portion of a radial extent of
the first quadrature burst field. The second quadrature burst field is radially
aligned with and away from the first quadrature burst field and spans a portion
of a radial extent of the second normal burst field. The first normal burst field
and the first quadrature burst field have a same first phase and the second normal
burst field and the first quadrature burst field have a same second phase. The
first phase is different than the second phase.