Faraday cage?

See ads for wallets that prevent skimming credit cards? Are those
considered Faraday cages? I was thinking I could laminate some AL foil
the size of credit cards and have one on top and bottom of the stack of
cards in my wallet to do the job. Sound feasible?
Reply to
Tom Gardner
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Sounds feasible. Stainless-steel or other low-corrosion mesh may be more durable, and if you ever need to make a bong in an emergency you'll have material to make the screen for the bowl.
Reply to
Tim Wescott
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Worth a try. A homemade duct tape and foil wallet worked better than 8 of 10 commercial products. By the way, RF jammers seem to be illegal.
Pete Keillor
Reply to
Pete Keillor
The sleeve the bank gave me with my debit card is al foil with paper laminated on both sides . I think the cards need to be more-or-less completely enclosed for that to be effective . Maybe an accordion fold set of sleeves ?
Reply to
Terry Coombs
Ummm, OK, but the only type of card (etc.) that is actually at risk is something with RFID technology in it. Your US Passport is one of those items. And, of course, many PDAs, tablets, phones, etc. can also be hacked by wireless devices.
But, CREDIT CARDS, especially those in use in the US, should be immune. There are only two kinds I have seen, mag stripe cards and chip cards. Neither of these can be compromised without actually TOUCHING the cards.
Skimming actually refers to planting devices IN the store's card reader to capture info from the card. You would have to take your card out of the wallet to make a payment.
Jon
Reply to
Jon Elson
Credit cards require physical contact, be it swiping the magnetic stripe or communicating with the chip within. Neither is RFID, and so cannot be skimmed from a distance.
Passports are quite another matter. They very much can be read from ten or twenty feet. I'm not sure how important it is to prevent this, but a sheet of 0.003" thick brass shimstock foil folded into the passport completely prevents this. This costs maybe a dollar.
It is not necessary to enclose the passport. So long as the foil is close to the antenna coil in the passport, it shorts the local field out quite well.
If the foil is not removed, not even the legit reader at passport control works. The officers at passport control do not get excited about this - just remove the piece of shimstock, and put it back in the passport later.
Joe Gwinn
Reply to
Joe Gwinn
Maybe in the US this true but I doubt it, contactless payment technology has been around in the UK for a few years at least and I would expect in the US as well, see
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, and has been in the news in recent days here as they are raising the
have one and not sure if I want one. A few years ago I was warned by friends in Holland about IIRC Oyster card travel payment cards being scanned while in your pocket and details/funds being withdrawn.
Reply to
David Billington
Credit cards in Australia have all three interfaces - wireless, chip contacts & mag stripe. All three are operable and are used.
Reply to
Kluge
I have about six in my wallet that will do contactless payment. Limit varies by vendor and by some kind of algorithm- sometimes up to $75 or more, other times a $20 payment will require chip+PIN. More times it won't work at all with Amex, but will with M/C or Visa even where all are accepted. It's actually faster than cash where the registers are set up for it.
It doesn't have a lot of range with the typical readers- maybe 1/2".
The 'Octopus' stored value cards they've been use in Hong Kong for more than a decade seem to have a bit more range- folks keep them in their wallet or purse and just flap it against the reader to pay subway fares etc.. I think some cell phones have it built in.
I think a bit of tin foil would work in the wallet. Maybe even the aluminized paper in cig packs (do they still have that?).
--sp
Reply to
Spehro Pefhany
The "pay-wave" or "touch-n-go" payment method is warmly embraced by thieves who clock up as much as they can before the card is cancelled. ;)
Reply to
Deez Nuts
It's easier than that. A credit-card sized chunk of brass or SS shim stock in close proximity to the card (next to it) will greatly attenuate any interrogation RF and load the 'antenna' so it doesn't respond. I just keep a business card from an electrochemical machining outfit in the wallet next to the RF-responding cards.
Or, there are metal-case 'wallets', if you can tolerate extra silliness.
Reply to
whit3rd
My bank said "Due to security, we have not issued any of these chipped cards, so all cards issued are safe."
Reply to
Larry Jaques
Great idea.. I think I have one or two of those kicking around from trade shows.
Or use the 'security edition' of the Bill of Rights..
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--sp
Reply to
Spehro Pefhany
The credit card companies have a zero liability policy and they don't let you (or anyone) go doing a whole bunch of PIN-less transactions in a row without checking once in a while.
I think it's safer than cash.
--sp
Reply to
Spehro Pefhany
Aluminized mylar works as well. They give you a bag made of the stuff if you have the EZ-Pass units. (also works real nice to tuck a company cell phone in when you don't want to deal with the BS for a while.... or at least I heard that somewhere, I would never have done that with the companies cell phone....)
Need a source? Dollar stores sell a lot of aluminized mylar in balloon form....
Reply to
Steve W.
Ditto here. My bank called once and asked "Did you just spend $1,200 at Fifi's Boutique?" After I stopped laughing, she said "I didn't think so. OK, we'll send out a replacement credit card within a week. Cut the other one up."
Another time, the card just showed up with a letter saying that they'd seen some strange activity and swapped cards, just in case. I love my bank!
Reply to
Larry Jaques
Just happened this evening, after I wrote the first response. I was at the Costco checkout and a call came on my cell phone from the West coast- it was the bank fraud department (the one that *detects* frauds, just to be clear) asking if I just spent $1039 at Ryan's Pet Supply (nope!). I just happened to be paying with the same card!
Funny thing is a somewhat paranoid friend who uses his card for almost nothing has had this happen too.
--sp
Reply to
Spehro Pefhany
Had a new card sent to me right after the big "data leak" that Master Card had. Letter inside said that they were "not sure" if my number was one of the hacked ones...
One thing I did notice though. My wife has a card through the same bank as does my FIL. I've made purchases with all three (they like to buy stuff but don't like using the computer!) All three cards have the same first number sets. Only the last 4 are different (and the ID number on the back) So in theory all you need would be to run those numbers sequentially till you found a sequence that works. With a computer that wouldn't take long. And with the way the act at checkouts these days (next time you use a card watch and see if they even look at the signature)fraud is probably REAL easy.
Reply to
Steve W.
A while back, just for kicks and grins when I was using a self check out somewhere I started signing my receipts with the names of Presidents. Two days ago I signed Herbert Hoover at Lowes. Today all the self check outs at Lowes were backed up so I went to one that was manned (personed?). When I tried to sign with my own name, the sig was rejected. After trying my sig three times the clerk had to print the receipt and have me sign that. I'm sure it was coincidental...
Steve
Reply to
SnA Higgins

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