[SOLVED] Debit Cards

[Requiem]

Riddle me this:
Why does folding a piece of paper (or thin plastic bag) over a debit card allow a stubborn card to be read? A lot of stores seem to have trouble with my card (although it works fine in ATMs and vending machines), but when they fold a receipt or piece of plastic over it before swiping, it works fine. What is it that makes that work???

[Dj Sneaky Whiskers]

Magic, obviously!

[N_Quire]

Haven't you heard? Plastic is better than cash at everything.

[J-Man]

I haven't heard that one before.
I'd guess that the paper is either positioning the magnetic tape at a better distance for reading or doing some type of capacitive effect, but I'm not sure why the latter would improve performance.

[BoulderHead]

I think department store checkout people use this trick quite often but don't know why either. I've heard the magnetic strip on the card is weak but even if that is true I cannot figure this one out. While searching for answers I found an interesting link speaking of something that I hadn't heard of before; 5 Gigs of hard disk space on a credit card;

http://www.pcworld.com/news/article/0,aid,108816,tk,dn011603X,00.asp

[GlamGein]

It has something to do with the electromagneticity (is that even a word?!). Cards also can work if you rub the strip with your shirt or sweater. Its like rubbing a balloon in your hair, and your hair stands up.