In a helical-scan tape system, the MR head is brought into contact with the
tape surface at high speed and is exposed to the atmosphere without a prot
ective coating. In this paper, we study the contact resistance between the
MR. head and tape in terms of tape surface resistance and voltage applied t
o the head. The electrostatic charge that accumulates on the tape surface a
s a result of running the tape was measured and found to be less than a few
volts. Corrosion tests were found to cause no electrical damage and no vis
ual change, and the block error rate remained constant after storage for 1
year and 5 months. We conclude that helical scan tape systems using the MR
head are reliable [1], [2].