Track-finding servomechanism utilizing the sampled output of an envelope comparison

摘要

A servomechanism finds an optimum location for a transducer relative to a track on a magnetic disk by sampling signal strength for a plurality of transducer trajectories. By processing the amplitude envelope of the recorded signal through a comparator prior to sampling, the comparator output, rather than the continuous signal envelope, is sampled. In this way a manageable amount of data is produced for tabulating a collection of integers that specify the cross-track distribution of signal strength across the trajectories. The best trajectory is selected and the transducer is moved accordingly to obtain the best playback signal.