Methods and systems for sensing a position of a transducer head with
respect to a storage medium. One method includes generating a read signal
from a servo track stored on a magnetic storage medium. The servo track
includes servo frames of magnetic flux transitions forming detectable
servo marks, the servo marks forming a tone field of repeating servo
marks oriented at a first azimuth angle and a mid-frame synchronization
mark incorporated within the tone field, wherein the tone field provides
a metric reference for dimensional measurements between features within
the servo frame(s). The number of servo marks in the tone field of each
servo frame along a longitudinal direction of the servo track before the
mid-frame synchronization mark and after the mid-frame synchronization
mark varies with lateral position.