bulk eraser การใช้

Using a bulk eraser, degaussing, or otherwise exposing the cartridge to a strong magnetic field, will erase the servo tracks along with the data tracks, rendering the cartridge unusable.
It is also possible to format a disk at a lower density than it was intended for, but only if the disk is first thoroughly demagnetized with a bulk eraser, as the high density format is magnetically stronger and will prevent the disk from working in lower density modes.
This design had the advantage that it could be used to demagnetize other metal parts of the tape path ( not just the actual record / playback heads ) however it required careful use ( to avoid " increasing " the magnetization of the heads ) and if used too close to actual cassette tapes could inadvertently act as a " bulk eraser ".