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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."
... just how strong the magnetic field is, for it to affect the hard drive of a computer at any likely distance. It seems like metal objects would be flying through the air and sticking to the floor. Also, I have to wonder how a static magnetic field would affect most phones. Seems there would have to be an alternating field of some sort to do so. Finally, any links to the 'numbers' (field strength, gauss, whatever the proper term is)?
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"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." And, their tinfoil hats were stuck to the ceiling.
Gives a whole new definition to "Attractive home in desirable neighbourhood"
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Have you ever tried to kill a harddrive with a magnet? It basically requires passing a rare earth magnet closely over the platters several times before the data is reliably damaged and if they had that kind of magnetic fields it would cause much bigger problems. And while I don't know to much about the properties EM radiation, I believe that magnetic fields don't interfere with radio waves.
My guess is that its the steel beams themselves are causing interference with the phones, that they incidentally had hdd failures (they have lived there for like 6 years), and the the steel beams have slight magnetic field because a small amount of current is passing through them (electricians like to ground to steel beams instead of running a ground line back to power box and putting to ground their) and they blame that weak magnetic field for their problems.
This is all purely speculation because they don't give any real details about the field.
If its just a couple of beams, it can be degaussed using a arc-welded and a few wraps of the arc-welds cables around the beam. There is a more to the procedure but the tools are easy to obtain. Did this in the Navy, wrap a submarine in about 300 turns of cable and run a few thousand amps through them.
The people who claim they are affected are just mixing things that, to their uneducated minds, are the same thing. Static magneticity, radio waves, same difference, right?
It reads like a bunch of BS. Do they still have CRTs in their TVs? In typical 2-story U.S. homes, there's structural steel in a few isolated places -- a beam or two in the basement, perhaps another beam and a column in the garage. That would, at best, cause some changes in color. It'd need to be substantial to cause geometric distortion of the image itself. You can have typical home speakers a few feet away from a color CRT and there's no effect. That structural steel would need to be magnetized quite well to see the effects they claim.
Hard drives won't be affected by any remnant magnetization of structural steel that's a byproduct of production, shipping and storage in varied conditions. Same goes for wireless devices -- static fields do nothing much to them. I'll read their case and perhaps pay them a visit, I need to see it to believe it.
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The summary reads like BS anyway.
If they actually have magnetic mono-poles in their house they should sell them for millions of dollars, instead of complaining about it.
No one describes a magnet as "positively charged".
Also charge is an entirely different property than magnetism.
It seems far more likely the beams are not properly grounded and are possibly acting like an antenna, causing all kinds of interference.
And unless they mounted their hard drives onto the "magnetic" beams I seriously doubt the field is strong enough to affect them.
Finally I have to wonder how would these beams get magnetized?
Did the electrician wrap some power cables around it?
I've got a bulk tape eraser. Which is an electro-magnet. Tried to erase a few laptop and 3.5 hdds with it. I could pick the drives up by it holding onto the scant bits of ferrous metal in them but was unable to blank any of them. I tried one drive for 3 minutes and it still booted an OS just fine. If they had beams that could corrupt their drives their keys, belts, zippers, furniture and every damn thing in the house with metal would be stuck to that wall before that drive got nailed. It's just normal lifetime use/failure of the drive.
Bad wiring, perhaps? Running electrical wires in close proximity to the steel joists could cause magnetization of the joists over time. Iron and its alloys are pretty easy to magnetize in that manner./quote
Last I checked we use alternating current in this country.
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Slashdot summary does not agree with the original article, which says the Supreme Court will only decide whether the couple has the right to sue (a matter of law). Only later might the question move to whether magnetized joists have caused any trouble, a matter of fact.
Hmm. I lined my last house with tongue and groove pine boards and noticed that adjacent boards contained slices through imperfections in the original trees. This is because the boards are produced, processed, transported and installed serially. So maybe the metal structural components of the house have a shared history? If they get heated in a foundry the magnetic poles will be free to align against the prevailing field, which could be quite strong if there is a lot of DC current around. Then they get stacked and installed in the house, still in the same orientation relative to each other.
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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; }
And this would affect their hard drives and TV how, exactly?
Seriously, if the beams were magnetic enough to cause the claimed damage to the contents of the house, they wouldn't have been able to separate them from each other in this construction pile you've theoretically stacked up. They wouldn't even have been delivered, because they wouldn't have been able to scrape them off the forklifts, or lift them from the truck beds. Other vehicles passing them on the roads would have been stuck to the sides of their trailers. Once delivered, the carpenters' hammers would have flown through the air, heads permanently affixed to the beams.
Yes, they could be magnetic enough to disrupt a compass reading. The earth's field is maybe 60 microteslas, so it's not a high bar to pass. But strong enough to erase a bit in a hard drive? The coercivity of the media is about 1700 Oe for cobalt, which takes a lot stronger field than that.
John
A magnetized hull is detrimental to a number of electronic warfare devices. We're not so worried about mines, or even being detected, so much as we're concerned about the proper functioning of sonar, radar, gunplot, computers, etc ad nauseum.
I have little idea whether TFS and TFA are accurate portrayals of the situation in Ohio, but I can say that the ships I served aboard had some interesting anomalies in navigation gear, tracking gear, and computers when the hull was highly magnetized.
And, that doesn't touch on preservation. A steel hull, and an aluminum superstructure poses a real challenge in the prevention of corrosion. Shipbuilders use a bimetal thing to join the aluminum to the steel, but even so magnetic and electrical charges in the hull tend to cause problems. Electrical more than magnetic, but still, the magnetism is something that they take into account.
To bad I didn't really study all this stuff when I was in. I am merely aware of the concern that the ship's officers and the hull tech people had about this stuff.
TL/DR part - all that I'm certain of, is that we routinely passed through a degausing station when we returned to port. A couple times, we turned around and passed through it again.
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I think checking alleged haunted houses for magnetic fields is standard procedure. The problem is, when they find the field, they decide it's evidence of paranormal activity.
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.
A static magnetic field has nothing to do with a 900 MHZ or whatever radio signal coming from the phone.
But it would take a very strong field to cause this. The phone would jump out of your hand and stick to the wall first.
Evidently, the coercivity of the media who reported on this story was high enough to be affected by these magnetic homes.
(Sorry, it was only until after I read your comment that I discovered which type of media you were referring to.)
I bet magnetic crane abuse. A crane with strong electromagnet instead of hook is normally used to transport beams and other heavy elements between storage and cargo, but the duration is not enough to magnetize the beams. But if the operator decided to "have some fun" and waved the electromagnet above the beams in one direction several times, or otherwise abused the process - say, moving the "head" over the same bundle of beams multiple times on return trip after loading a bundle on a trach and going back for another, they could have become magnetized.
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Flat sheet steel does little to curb static magnetic fields.
Experiment: Find a CRT, and a magnet. Observe how they behave together. Next, put something steel (the side from a PC case?) between the two, and observer that they behave almost the same... Feel free to repeat with iron filings, aluminum and steel cans, old license plates, or whatever. It shields somewhat, and does a bit of scattering, but it's lousy (and certainly not "very good").
One can use an appropriately curved chunk of curved steel to accomplish some shielding. See, for instance, shielded speakers, which use a cup to completely surround the magnet, sometimes in addition to a second magnet which is only used to help counteract the external field of the first.
But, you know, your PC case isn't shaped like that.
There are certain high-permeability materials (Mu-metal being one) which do far better, but they're pretty far removed from the common mild steel of a PC. (I haven't verified this, but I've read that Mu-metal is used on the back side of the neodymium magnets inside of a hard drive, and if that is the case it would easily explain how one side sticks ferociously to the side of the fridge, and the other side won't even pick up a paper clip.)
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