Variations in recorded flux transitions with distance from track center

This experimental investigation used special techniques to determine if all parts of a digital flux transition across the width of the track are uniform and contribute uniformly in amplitude and phase to read signal pulses. Previously reported "edge profile" techniques were used to observe visually reduced dimensions of single-pulse flux transitions recorded near the outer edges of the head core, with various recording heads. Digital signals were recorded on the edges of magnetic tapes at different positions along the gap-edge-axis of the recording head, to determine that the normalized read signal amplitude ≥0.8 over the center 99 percent (average value) of the recording head core width, but is zero beyond the center 105 percent (average value) of the head core width. Comparable experiments where read head position was varied resulted in normalized read signal amplitude ≥ 0.8 over the center 96-99 percent of the core width. Read signals were detected up to 30 percent of the core width beyond the core edge, a wider track than a comparable head would record. Experimental evidence suggests that the read signal pulses may include phase shifted contributions from the ends of curved flux transitions, where the ends were recorded closer to the trailing edge of the head gap.