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Ohio Supreme Court Drawn Into Magnetic Homes Case
The Ohio Supreme Court will decide if a builder will have to replace magnetized parts of two couples' homes, even though they signed a limited warranty which did not specifically cover replacing positively- or negatively-charged building materials. After moving into the homes the couples found that something was not quite right. Their TV screens were distorted. Cordless phones ran into interference. Computer hard drives were corrupted. Soon after, it was discovered that steel joists in the homes had become magnetized."
but the casing of (all?) commercial HDDs is designed to attenuate magnetic fields. this is because there is a great big honking rare earth magnet built right into the drive, just inches away from the platter. It is used to drive the voice coil actuator that moves the head around. Having that just a few inches away from floppy diskette drives (now a rarity, but still) without such attenuation would have been "Bad, M'kay."
to not only have sufficient magnetic flux at the platter surface, but also be sufficient to cause electrical eddies inside the platters due to the rotation, the walls would have to be several million tesla in magnetic potential.
Flying forks and hallucenations would be occuring long before this would become a problem.
Have you ever taken a hard drive apart? There's a couple of real nice rare earth magnets in there for the voice coil, less than 3 inches from the heads, and maybe an inch from the platters. It would take one hell of a magnet to equal that strength at any distance, much less exceed it. It takes a lot of magnetism to flip the fields in those platters. The heads can provide that strength, just over a very small area.
#naabhaprzrag, #sverubfr-000, #agi-fcbafberq, negvpyr[pynff*=' negvpyr-ary-'] { qvfcynl: abar !vzcbegnag; }
The whole thing is BS. I work (mostly used to work) with MRI equipment, both supercon and smaller permanent magnet based instruments. I have some permanent magnets for building MRI machines that have a surface field strength of about 0.5T (5000 Gauss) which would crush your finger to a pulp if it ever got stuck between them, and are all but impossible to separate if they ever get near each other. I have routinely used a PC within a few feet of these without any ill effects. If I had to guess, the 5 Gauss line, normally considered the safe distance for magnetic storage media, is maybe a foot. If the steel beams in this house are magnetized, I would be amazed if the remanent magnetization was even 5 G. No chance of there being such a large field (this is 10x earth's field) more than a few inches away from the beams, regardless of their magnetization. Furthermore, a permanent magnet would have no effect on cordless phones of any kind. A static magnetic field has nothing to do with a 900 MHZ or whatever radio signal coming from the phone.