Make us your home page

Today’s top headlines delivered to you daily.

(View our Privacy Policy)

Q&A: Tricks for credit card swipes

Tricks for credit card swipes

The other day I was at a major grocery store checking out. The lady in front of me was going to pay using her credit card. She swiped it, several times, yet the machine wouldn't read her card. The clerk took the card and placed it in a regular plastic grocery bag, snugging the bag around the card. She passed it through the machine, which read the card the first time. What did placing the card in the plastic bag do?

There are a whole bag of tricks used by retail clerks to get their machines to accept credit cards. This is one of them.

Experts in the industry say that the magnetic stripe on the back of credit cards can be contaminated by all sorts of things — dust, dirt, scratches, temperature extremes, even exposure to other magnetic stripes that can corrupt the data from yours.

And there can be problems with the machines and cards. Norman Castner, countertop product business unit manager of Hypercom, which makes the machines that accept credit cards, told that his company's machines are expected to last up to five years, or up to 300,000 transactions. The magnetic strip on the back of the card isn't likely to last half that long, which is one reason you get new cards every couple of years.

So when something happens and a machine doesn't accept your card, experts say you can try to improve the swipe by wiping the back of the card off on your sleeve or clothes. Or you can wrap your card in a dollar bill or register receipt and try again. Some people have even been known to lick the stripe, though that's not recommended.

If the problem persists, some enterprising people and clerks cover the stripe with Scotch tape or put the card in a thin plastic bag. That can work because it increases the distance between the magnetic stripe and the head of the reader, blurring or softening the signal the stripes give out, another Hypercom spokesman told

"In lab testing, it has been shown that doing that does reduce some of the noise that the card interaction creates, and sometimes that can result in a good swipe," said Hypercom spokesman Pete Schuddekopf. "The serious downside to that approach is that the material that is being used can become lodged in the terminal swipe channel and even damage the reader."

43 supercentenarians are living

How many people alive today were born in the 1800s?

As of Aug. 30, there were 43 people in the world who were born in the 19th century, according to the Gerontology Research Group ( The group tracks supercentenarians, a term used to describe a person who is at least 110 years old.

The oldest is Besse Cooper of Monroe, Ga., who turned 115 on Aug. 26. She was born in 1896.

Q&A: Tricks for credit card swipes 09/04/11 [Last modified: Sunday, September 4, 2011 4:30am]
Photo reprints | Article reprints

© 2017 Tampa Bay Times


Join the discussion: Click to view comments, add yours

  1. Police: Uber driver's gun discharges during fight at Adventure Island in Tampa

    Public Safety

    TAMPA — An Uber driver's gun went off Sunday at Adventure Island during a fight between the driver and two passengers.

  2. Baker cautious on Pride politics


    Rick and Joyce Baker strode down Central Avenue Sunday amid rainbow flags, corporate booths, and blaring music of the St. Pete Pride Festival.

    St. Petersburg mayoral candidate Rick Baker chats Sunday with people at the St. Pete Pride Festival. As mayor, Baker did not sign a Pride parade proclamation, but now he says he would.
  3. Rays' bullpen stars lit up in loss to Orioles

    The Heater

    ST. PETERSBURG — Saturday it was the soft underbelly of the bullpen that let one get away from the Rays, incurring the wrath of the team's faithful followers, who wondered why the high-leverage guys weren't pitching.

    Rays closer Alex Colome, coming in with the score tied in the ninth, allows three runs in his second straight poor outing.
  4. Lightning among early suitors for defenseman Kevin Shattenkirk

    Lightning Strikes

    TAMPA — Lightning general manager Steve Yzerman said he planned to explore free agency for potential needs, which include bolstering his blue line and adding a wing or two.

    Defenseman Kevin Shattenkirk, who can be a free agent Saturday, counts the Lightning among his early suitors.
  5. Senate leaders try to appease members as support for health bill slips


    WASHINGTON — Senate Republican leaders scrambled Sunday to rally support for their health care bill, even as opposition continued to build outside Congress and two Republican senators questioned whether the bill would be approved this week.

    Sen. Rand Paul of Kentucky, speaking to reporters on Capitol Hill on Thursday, is one of the five Republican senators who announced they cannot support the health care bill as drafted.