Erasing with magnetic fields
The degausser is a device in which a strongly varying magnetic field is generated. In this magnetic field, the hard disk is placed. Generation of the field is done with a coil and alternating current. By the way, we invariably read things about “radiation” from manufacturers and users of degaussers, but magnetism is not radiation, it is a field.
In a hard disk, the information is stored magnetically on disks and the magnetic fields of the degausser magnetize the disks. Alternately one way or the other. As a result, all information is then lost.
At least this is the theory; in practice, however, it does not appear to work like this.
How does a degausser work
With a hard disk, the spinning disks are mounted in a magnetically shielded space called a Faraday cage. This is the aluminum casing of the hard drive. The hard disk manufacturer has spared no expense to make a magnetically dense safe for the spinning disks containing information. This was done to prevent information from being lost if a hard disk comes near a changing magnetic field.
Thus, the changing magnetic field cannot reach the disks and data. Thus, no data is destroyed at all. Still, a hard disk will not work if it has been in the degausser. However, this has an entirely different reason: Microelectronics and microchips do break down immediately from alternating magnetic fields.
This is because in wires, PCB traces and other conductors, electric current is generated that immediately destroys the sensitive electronics. So what actually happens is that the circuit board (called “module”) on the back of the hard disk is destroyed but the data inside the hard disk remains completely intact.
Check the facts
We at IT recycling have done experiments with this and this indeed showed that all the data was still on the hard drives after degaussing and only the circuit board was defective.
So degaussers are more for people who believe in all kinds of strange and elusive types of radiation that are not actually radiation but a field.
For everyone else, degaussing just doesn’t work. Do you want your hard drives really destroyed? Then contact us and we’ll make sure nothing is left over in terms of data.