Abstract: A triple track test for determining respective erase band widths associated with a read/write head involves writing first and second data tracks in each direction and at a certain distance from an origin, and erasing a track having a center at the origin. Based on a triple track test profile (3T) corresponding to the three tracks, a first distance is measured in one direction from the origin to one of the modified data tracks and a first erase band width is computed based thereon. The other side erase band width is computable similarly. A side erase amplitude loss measurement procedure, for determining the amount of signal amplitude lost by an adjacent track due to the respective erase bands, involves constructing a side-erase profile based on a composite of the 3T profile and a full-track profile, from which respective amplitude losses are computed for the respective erase bands.

Abstract: A triple track test for determining respective erase band widths associated with a read/write head involves writing first and second data tracks in each direction and at a certain distance from an origin, and erasing a track having a center at the origin. Based on a triple track test profile (3T) corresponding to the three tracks, a first distance is measured in one direction from the origin to one of the modified data tracks and a first erase band width is computed based thereon. The other side erase band width is computable similarly. A side erase amplitude loss measurement procedure, for determining the amount of signal amplitude lost by an adjacent track due to the respective erase bands, involves constructing a side-erase profile based on a composite of the 3T profile and a full-track profile, from which respective amplitude losses are computed for the respective erase bands.

Abstract: A method for calibrating a fly height adjustment device comprises flying a magnetic transducer coupled with a head gimbal assembly at a fly height from a magnetic recording data track. The magnetic transducer is coupled with a fly height adjustment device. Read-back signal amplitude is read from the magnetic recording data track with the magnetic transducer. The fly height is decreased with the fly height adjustment device. A linear fly height prediction is generated from the read-back signal amplitude and from power delivered to the fly height adjustment device as the fly height is decreased. The power delivered to the fly height adjustment device is compared with a difference between the linear fly height prediction and an implied fly height from the read-back signal amplitude, thereby calibrating the fly height adjustment device.

Abstract: A method for calibrating a fly height adjustment device comprises flying a magnetic transducer coupled with a head gimbal assembly at a fly height from a magnetic recording data track. The magnetic transducer is coupled with a fly height adjustment device. Read-back signal amplitude is read from the magnetic recording data track with the magnetic transducer. The fly height is decreased with the fly height adjustment device. A linear fly height prediction is generated from the read-back signal amplitude and from power delivered to the fly height adjustment device as the fly height is decreased. The power delivered to the fly height adjustment device is compared with a difference between the linear fly height prediction and an implied fly height from the read-back signal amplitude, thereby calibrating the fly height adjustment device.

Abstract: One embodiment in accordance with the invention is a method for measuring a track width for a magnetic recording head comprising writing a first track and a second track on a disk at two different positions. Note that the first track is written at a frequency plus a frequency shift value while the second track is written at the frequency minus the frequency shift value.

Abstract: A method for operating a tester for testing heads and disks of a magnetic recording disk drive during manufacturing calculates the readback signal amplitude asymmetry in the frequency domain without the need for measurement in the time domain with a peak detection channel. The tester first signals the write head to write a first pattern on the disk to generate a readback signal with positive pulses. The read head then detects this first recorded pattern and sends the readback signal to a spectrum analyzer connected to the tester. The tester then signals the write head to write a second pattern on the disk to generate a readback signal with negative pulses. The read head then detects this second recorded pattern and sends the readback signal to the spectrum analyzer. The spectrum analyzer measures the amplitudes of the first and second readback signals in the frequency domain using a bandpass filter.

Abstract: One embodiment in accordance with the invention is a method for measuring a track width for a magnetic recording head comprising writing a first track and a second track on a disk at two different positions. Note that the first track is written at a frequency plus a frequency shift value while the second track is written at the frequency minus the frequency shift value.

Abstract: A method for operating a tester for testing heads and disks of a magnetic recording disk drive during manufacturing calculates the readback signal amplitude asymmetry in the frequency domain without the need for measurement in the time domain with a peak detection channel. The tester first signals the write head to write a first pattern on the disk to generate a readback signal with positive pulses. The read head then detects this first recorded pattern and sends the readback signal to a spectrum analyzer connected to the tester. The tester then signals the write head to write a second pattern on the disk to generate a readback signal with negative pulses. The read head then detects this second recorded pattern and sends the readback signal to the spectrum analyzer. The spectrum analyzer measures the amplitudes of the first and second readback signals in the frequency domain using a bandpass filter.