Hall playback measurements of a tape remanence profile and related stress effects

The high resolution and dc response of a Hall effect playback head allows one to measure details of the individual bits of a recorded signal as a tape is moved very slowly past the head. Using this method, the demagnetization, as a function of recorded wavelength, that is produced by rubbing tapes a different number of times is compared with the loss in signal due to repeated playback, and with earlier rubbing measurements on a dc magnetized tape which were made with a large Hall probe and a vibrating sample magnetometer.