An alternating current (AC) bulk eraser (degausser) is used for complete erasure of data and other signals on magnetic media. Degaussing is a process where magnetic media is exposed to a powerful, alternating magnetic field. Degaussing removes any previously written data, leaving the media in a magnetically randomized (blank) state.

The degausser must subject the media to an alternating magnetic field of sufficient intensity to saturate the media and then by slowly withdrawing or reducing the field, the magnetic media is left in a magnetically neutral state.

To erase recorded data, it is necessary for the strength of the degaussing field to be greater in value than the coercivity of the magnetic media. Simply stated, coercivity is the magnetic field strength, rated in oersteds (Oe), required to change the magnetic orientation of the magnetic material. Check with knowledgeable dealers or degausser manufacturers to identify degausser models that meet your requirements.

Data is typically not lost until its level has been decreased 65% to 75% (or more) below its original saturation recording signal level, dependent upon the drive system.

 

For more information on visual basic msflexgrid erases row data recordset, erasing hard drives, degaussing equipment, and degaussing services, see also: computer degausing v-860 tape eraser erase data cd and microwaves v-880 tape eraser 1200 cd eraser erase bad credit file scrub secure erase hard disk mssql 2000 cleaning data repeating field separators per-4516 eraser hard drive file cleaning software v92 hard drive degausser digi tapemaster v-890 video tape eraser v-94 video tape eraser v92 video tape eraser v-860 tape degausser degausing television screen wipe hard drive clean software cleaning hard drive before selling computer v92 video tape degausser how to delete all data from hard drive used computers v92 video tape eraser basic instructions on how to delete a hard drive partition mds5 hard drive eraser hard drive clean up reviews sv91m diskette eraser clean gb of memory from hard drive pf252 tape degausser erase free disk space mac 1200 cd eraser erase hard drive mircrosoft erase your harddrive v-860 video tape eraser degaus zenith tv v-860 video tape degausser v-860 video tape eraser per-1100 hard drive eraser freeware erase internet files mds5 eraser healthy climate air cleaner media

A complete erasure level, for most users, is considered to be 60 dB below the original signal level – this of course depends on user requirements. A 60 dB signal decrease equates to reducing the signal to one tenth of one percent of its original value.

Magnetic media products that have factory prerecorded magnetic servo patterns should not be degaussed. Degaussing would erase the factory written magnetic servo signals and leave the media unusable. For all other magnetic media (without magnetic servo signals), after proper degaussing, the quality of subsequent data recording should be unchanged or even improved.

It is very important to understand and follow the degausser’s operating instructions. This is especially important for manual units where the operator controls the media’s movement through the degaussing field. For higher coercivity media, four passes are often recommended – two passes, with a 90 degree rotation for the second pass, and then repeat the process with the media turned upside-down. Of course, these and other important operating considerations will vary with the type, power and construction of the individual degausser models.

For more information on visual basic msflexgrid erases row data recordset, degaussers, erasing hard drives, cleaning hard drives, degaussing, and erasing harddrives, see also: