The simulation picture at right shows our pair of DX0X8 magnets on either side of the disc platters. This pair was chosen based on some studies of what arrangements would produce the strongest field within the drive. We hoped that we might be able to at least affect the outermost platters, even if the inner ones might be shielded by them.
Most of the instructions we've seen say to rub the magnet several times across the face of the drive. With our arrangement, the drive is actually spinning at 7, RPM. We're pretty sure it's passing over the drive multiple times! We also rubbed some very large magnets, like our 3" diameter DZ0X8-N52 , across the hard drive with the drive turned off. We figured we could use these large magnets without causing mechanical damage when it wasn't running.
When re-checked, the drive still showed no errors! None of the data was changed at all. Some older types of magnetic storage media can be erased with neodymium magnets. The magnetic stripe on your credit card is one example. Audio cassettes and VHS video tapes are another. The material's coercivity, or resistance to being demagnetized, is lower than the field made by the magnet. You can look up the coercivity numbers for these materials, all of which are usually in the Oersted range.
The more we researched the topic, the more we found conflicting data on the coercivity of hard drive materials. One source said 1, Oe, another said 2, Oe. It seems that, in the race to make hard drives of greater storage capacities, hard drive manufacturers keep finding higher coercivity materials for the hard drive platters.
The later the manufacturing date of your hard drive, probably the higher the drive's coercivity will be. We searched for hard drive erasing services, figuring we could learn something by finding out what such companies provide. Most companies either use strong degaussing machines that produce a strong an alternating magnetic field with an electromagnet, or shredders to physically destroy the drive.
As hard drive coercivity improves, physical destruction is becoming the more popular method. We didn't try every possible combination of magnet and erasure method. Since our methods failed to alter a single character of a single file, though, we wouldn't trust it to delete ALL the data. Our results make us doubt that neodymium magnets are sure to erase all the data. If you have a proven method that works for you, we'd love to hear about it.
Carefully under all the visible screws. Hard disc drive with screws removed. Remove all the necessary stickers. Concealed screws. Remove the cover. The magnets are under the triangle plate. Both magnets removed. One magnet out, one to go. Computer circuit components are able to store data in terms of whether current is present or not, represented by a 0 or 1. The north and south poles of the tiny neo magnets on the surface of hard disk drives can represent either 0s and 1s, making them perfect for computer data storage.
An electromagnetic head is used to store data into these cells since an electromagnet can reverse its own polarity by reversing the direction of current flowing through it—enabling it to rearrange the polls of the tiny hard disk drive magnets. The same head can also read the data stored on the hard disk drive. Some headphones, voice coil motor and earbuds, too. Cooling Fans A motor is a necessary part of an electrical fan, and all motors contain magnets since they use magnetism and electricity to induce motion.
In computers, fans are used primarily for cooling purposes and are mounted on all major heat-generating computer components including the processor, the power supply and high-end graphics cards. In some computers, there may be additional fans in the casing to offer enhanced cooling and ensure smooth performance.
0コメント