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Geek toys

Back in the States, I used to buy magnets from these guys — K&J Magnetics. They sell magnets in all strengths, sizes and shapes, because you never know when you want to stick something to something else or find a screw in a leafpile. If you know what I mean. Oh, don’t question me.

Anyway, the send out *lots* of mailings and a few interesting articles, such as this one, about magnetic strip technology. How it works, how to fuck it up.

Can a neodymium magnet erase or scramble the data on a magnetic strip?

Yes. If you rub a neodymium magnet directly across the magnetic stripe, with the magnet touching the card, the data is likely to be erased or scrambled.

How strong must the magnetic field be to erase these magnetic strips?

The magnetic strip on credit cards come in two varieties. The high-coercivity ones, like a typical credit card, require a field strength of somewhere around 4,000 gauss to demagnetize. The low-coercivity ones that are often re-written, like hotel keys or gift cards, require about 300 gauss.

Worth a read, if you have the slightest interest.

I recommend these guys for all your magnet needs. And I trust that you would never, ever fuck up somebody’s credit cards without a really valid reason. You’re just too good a person.

sock it to me

January 7, 2014 — 11:50 pm
Comments: 11

So. Here we are.

Yesterday was Twelfth Night, the traditional end of the Christmas festivities (if you’re in the BBC viewing area and you missed the Tudor Monastery Farm series, go watch it. Or at least the Christmas special).

So, Christmas is over, and here we are again.

I call this picture, “kitten on my goddamned desk, goddamn it.”

sock it to me

— 12:41 am
Comments: 17