Servo channel equalization network

Claim 2

In a system for following a target path, said system deriving a first path following signal from a first servo path on one side of said target path and a second path following signal from a second servo path on the other side of said target path, means for generating 100 percent off-track conditions comprising a first portion which contains said first signal on both said servo paths, said portion located on said servo paths so that said first signal is derived from each of said servo paths during a first common time period to generate a 100 percent off-track condition, a second portion which contains said second signal on said servo paths, said second portion located on said servo paths so that said second signal is derived from each of said servo paths during a second common time period to generate a second and different 100 percent off-track condition.

Claim 3

The system of claim 1 further including means for comparing said two 100 percent off-track signals and means for adjusting said 100 percent off-track signals to balance one another.

Claim 4

In a magnetic recording disk device containing concentric tracks of recorded information on the surface of the disks and transducing heads to read and write said information, a servo system for maintaining the track following accuracy of a transducing head wherein a special sector of recorded information is placed in at least some of said tracks on said disks, said special sector comprising two portions wherein a first portion contains a first servo signal on adjacent tracks, said first portion beginning at a first radial on each said adjacent track and ending on a second radial on each said adjacent track, a second portion which contains a second servo signal on said adjacent tracks, said second servo signal different from said first servo signal, said second portion beginning at a third radial on each said adjacent track and ending on a fourth radial on each said adjacent track, so that said servo system can be tested for 100 percent off-track conditions and said conditions can be equalized to compensate for errors extraneous to proper operation.

Claim 5

In a magnetic recording disk device containing concentric tracks of recorded information on the surface of the disks and transducing heads to read and write said information, a servo system for maintaining the track following accuracy of a transducing head wherein a special sector of recorded information is placed in at least some of said tracks on said disks, said special sector comprising two portions wherein a first portion contains a first servo signal on adjacent tracks, said first portion beginning at a first radial on each said adjacent track and ending on a second radial on each said adjacent track, a second portion which contains a second servo signal on said adjacent tracks, said second servo signal different from said first servo signal, said second portion beginning at a third radial on each said adjacent track and ending on a fourth radial on each said adjacent track, so that said servo system can be tested for 100 percent off-track conditions and said conditions can be equalized to compensate for errors extraneous to proper operation.

Claim 6

The system of claim 3 further including means for comparing said two 100 percent off-track signals and means for adjusting said 100 percent off-track signals to balance one another.

Claim 7

In a system for following a target path, means for producing a first signal to move toward said path from a first direction, means for producing a second signal to move toward said path from a second direction, comparator means for comparing the first and second signals to produce a position error signal if said two compared signals are not in balance, means for suspending the operation of said comparator means and generating a 100 percent off-track first signal and a 100 percent off-track second signal, means for comparing said 100 percent off-track signals, and means for adjusting one of said 100 percent off-track signals to bring them in balance.

Claim 8

In a system for following a target path, means for producing a first signal to move toward said path from a first direction, means for producing a second signal to move toward said path from a second direction, comparator means for comparing the first and second signals to produce a position error signal if said two compared signals are not in balance, means for suspending the operation of said comparator means and generating a 100 percent off-track first signal and a 100 percent off-track second signal, means for comparing said 100 percent off-track signals, and means for adjusting one of said 100 percent off-track signals to bring them in balance.