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 clean program from hard drive completely, erasing hard drives, degaussing equipment, and degaussing services, see also: grid data security how to clean up your hard drive to make more room data link layer security how to erase a cd r clean hard drives media cleaner profiles download what can i do to clean up my hard drive key to installing an upgrade cd in a clean hard drive hard drive wipe xp v91m hd hard disk drive degausser grid data security compact disk data security how to erase a video tape hard drive erase program erase files software totally erasing a hard drive how do magnet erase tape memory hard disk clean up software free honeywell media air cleaner will mother board failure erase data on hard disk how to wipe hard drive data warehouse control and security how to clean up your hard drive hard drive clean sweep how degaussing works windows 3.1 disk erase delete files from hard drive erase disk erase cd freeware hard disk clean up software recuperate erase files erase a hard drive permanently degauss coil wand media cleaner reviews politician wipes hard drive delete hard drive to reinstall windows 98se computer virus erases data on hard drive what is degauss posistor clean hard drive xp what is degauss posistor

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 clean program from hard drive completely, degaussers, erasing hard drives, cleaning hard drives, degaussing, and erasing harddrives, see also: