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 windows xp delete unnecessary files second hard drive, erasing hard drives, degaussing equipment, and degaussing services, see also: hard drive dod wipe healthy climate air cleaner media v-860 tape eraser per-1100 diskette degausser cds 2500a feed hopper tape degausser whole-house media air cleaners v92 degausser v-860 degausser td1b tape degausser erase data cd and microwaves mds5 hard drive degausser cleaning hard drive before selling computer delete hard drive win 98 pc hard drive cleaning per-4516 eraser degauser make hard drive erase utility v-860 tape eraser cleaning up a hard drive hard drive erase utility cds1500 tape eraser visual basic mshflexgrid erases row data recordset hard drive dod wipe per-1100 disk eraser steps for cleaning data in a data warehouse degauser make v-860 video tape degausser dlt cleaning 1200 cd optical nsa approved make clean room hard disk how to erase files from hard drive mssql 2000 cleaning data repeating field separators pc hard drive cleaning per-4516 tape degausser v-880 degausser clean hard drive for free clean gb of memory from hard drive destroy hard drive data mds5 hard drive degausser v-860 tape degausser

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 windows xp delete unnecessary files second hard drive, degaussers, erasing hard drives, cleaning hard drives, degaussing, and erasing harddrives, see also: