Maximizing the Output from Buried Servo by Servo Write Current Shaping
Original Publication Date: 1981-Aug-01
Included in the Prior Art Database: 2005-Feb-12
Linear AC bias recording used so far for recording buried servo restricts the level of magnetization to about 1/3 of the saturation level of the medium. Beyond this level, harmonic distortions set in. Harmonic distortions are undesirable in buried servo since they interfere with the reading of data recorded on top. The present process provides a method of eliminating harmonic distortions in AC bias recording of buried servo at high magnetization levels. The method constitutes the use of complex waveforms for the write current to obtain the desired magnetization with near saturation amplitude and to obtain the desired undistorted output waveform. This waveform of the signal current for a desired output waveform can be determined either analytically or experimentally.