JREF Homepage Swift Blog Events Calendar $1 Million Paranormal Challenge The Amaz!ng Meeting Useful Links Support Us
James Randi Educational Foundation JREF Forum
Forum Index Register Members List Events Mark Forums Read Help

Go Back   JREF Forum » General Topics » Science, Mathematics, Medicine, and Technology
Click Here To Donate

Notices


Welcome to the JREF Forum, where we discuss skepticism, critical thinking, the paranormal and science in a friendly but lively way. You are currently viewing the forum as a guest, which means you are missing out on discussing matters that are of interest to you. Please consider registering so you can gain full use of the forum features and interact with other Members. Registration is simple, fast and free! Click here to register today.

Tags credit , unreadable , question

Reply
Old 12th August 2003, 07:04 PM   #1
BTox
Graduate Poster
 
Join Date: Jul 2003
Posts: 1,588
Question about unreadable credit cards

One for the physicists,electrical engineers and/or computer scientists - on occasion when I swipe my credit card at the supermarket, it comes up "unreadable". The kid at the register hands me a plastic bag, I put the card in the bag and swipe again, and it works. What's going on? Something to do with static electricity is my only guess, but I would think the plastic bag would exacerbate the problem.
BTox is offline   Quote this post in a PM   Nominate this post for this month's language award Copy a direct link to this post Reply With Quote Back to Top
Old 12th August 2003, 08:04 PM   #2
Goshawk
Graduate Poster
 
Goshawk's Avatar
 
Join Date: Jan 2003
Location: Decatur, Illinois, USA
Posts: 1,453
http://money.howstuffworks.com/credit-card3.htm

Quote:
If the ATM isn't accepting your card, your problem is probably either:

A dirty or scratched magstripe

An erased magstripe (The most common causes for erased magstripes are exposure to magnets, like the small ones used to hold notes and pictures on the refrigerator, and exposure to a store's electronic article surveillance (EAS) tag demagnetizer.)
The problem with your card is probably "dirt", which the baggie covers up.
Goshawk is offline   Quote this post in a PM   Nominate this post for this month's language award Copy a direct link to this post Reply With Quote Back to Top
Old 13th August 2003, 06:29 AM   #3
arcticpenguin
woo ban clan
 
Join Date: Sep 2002
Posts: 5,717
I have never heard of this, but could come up with possibilities.

Perhaps the reading of the card is marginal, for whatever reason, and swiping it several times would result in a good read regardless of the presence of the bag (i.e. the bag use is superstitious)

Perhaps the thickness of the bag improves the spacing between the magnetic strip on your card and the read head.
__________________
The power of accurate observation is frequently called cynicism by those who don't have it. - George Bernard Shaw
arcticpenguin is offline   Quote this post in a PM   Nominate this post for this month's language award Copy a direct link to this post Reply With Quote Back to Top
Reply

JREF Forum » General Topics » Science, Mathematics, Medicine, and Technology

Bookmarks

Thread Tools

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump


All times are GMT -7. The time now is 12:58 AM.
Powered by vBulletin. Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
2001-2013, James Randi Educational Foundation. All Rights Reserved.

Disclaimer: Messages posted in the Forum are solely the opinion of their authors.