Reader Amanda writes , “ I was a bank clerk for a few years and when the cash register would n’t interpret a course credit posting , we would roll the posting in a plastic udder and run it through again and it would work . What makes the cash register register the card when it ’s wind with a plastic bag ? "
The pitch-black stripe on the back side of the course credit lineup is made up of a gang of tiny charismatic corpuscle bound in credit card . The atom are arranged in magnetic and non - magnetized “ zona ” to encode the data — like your account number , exit date , etc.—that the bill lector on the register needs to process the dealings . When you cabbage the card , the card reader learn the info by observe the changes between the geographical zone . For the transaction to work , the information need to get from the circuit card to the lecturer to the computer without any errors .
The strip is pretty delicate , and the datum on it can be demoralize by display it to a secure attracter or chafe it . Damage can also occur step by step with function and carrying the card around in your notecase . Over time , some of the magnetised particle can get embroil out of position in a process calledsmearing . If enough magnetic minute move into a non - magnetised space to create a weak signal , the data gets corrupt and the carte du jour reader gets an error .
With just a small bite of magnetic material in them , the contaminated non - magnetic zones still have a much lower magnetic strength than the parts that are supposed to magnetized . Increasing the aloofness between the card reader and the corrupted zones is enough to get the reader to read those weak part as non - magnetize again . A plastic dish , usually at - hand at the immediate payment cash register , makes a great spacer . Wrapped around the card , the bag essentially damp the corrupted parts of the magnetic stripe so the reader is present with the data as its theorise to be .
