Barber-poling

Instead of two sensors it is also possible to use an AMR gradiometer, in which the two arms of the bridge are spatially separated. The barber poles have the same orientation in the two arms, so that only a field difference between the two positions is sensed. This configuration is not disturbed by interfering fields and has the advantage that it contains only one device. Therefore, it is not affected by element-to-element variations in sensitivity, offset, or temperature behavior. 

Since for some applications the linearity even with barber-pole biasing is not sufficient, the use of compensating coils as described for the Hall sensors are necessary. In AMR devices these coils can be directly integrated above the sensing structures, so that the advantageous compact size of these elements remain [6, 7]. 

After the first piercer, the maximum surface temperature was 2100 F, and when the round was rolled down into the discharge conveyor, distinctive barber poling was seen. Maximum furnace production was 110 tph. 

Obviously, some of these increases overlap therefore, a conservative figure of only 25% increase has been used. A recent installation of enhanced heating to only 40% of a furnace resulted in an output 1.29 times the original. A bonus will be elimination of barber poles in seamless mill rounds leaving the first piercer by using enhanced heating in the last 15 min of their heating time in a rotary furnace. 

Visitors to Pole Station like to have their picture taken beside a barber pole topped by a silver globe surrounded by the flags of the Treaty Nations (Fig. 2.13). This pole is not at the precise location of the geographic South Pole because the East Antarctic ice sheet is sliding on its base which means that the true position of the South Pole must be redetermined annually. 

Sliding diagonal An pattern that checks for address decoder problems, sense amplifier faults, and sense amplifier recovery. This test is a pattern that generates a diagonal of data in a field of complement data, and slides the diagonal of data in the X direction, creating a barber pole effect. 

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