A narrower side erase band for use with helical scan tape systems

The MFM technique is very useful to measure the side erase band. MFM images were processed by FFT to measure the side erase band width and effective track width. Compared with the electromagnetic properties produced using the MR head, the measuring point is defined on FFT processed data. Mrt of the tapes (thickness of magnetic layer), type of recording head and recording frequencies were varied for the sample tapes. The track width of low Mrt tapes showed good stability in different combinations of recording frequency. The side erase band width was reduced when a trimmed MIG head was used. The influence of the recording current for the side erase band was negligible.