Stop RFID cards from interfering with each other
October 1, 2015 3:39 PM Subscribe
I have a stack of 4 cards, 3 of which have RFID. When I tap this stack of cards on readers, they interfere with each other, and nothing gets read. What can I do to ensure that the card closest to the reader gets read? Can I buy or create some kind of shielding card to put behind the bottom card, in order to prevent interference with the other RFID cards?
I say "stack", but it's one of those thin card sleeve things that acts my wallet. Ideally, I'd be able to choose which RFID card to use simply by flipping over the card sleeve and tapping the desired card against the reader. Right now I have to remove the card from the sleeve and tap it by itself.
The internet tells me a piece of aluminum foil sandwiched between the offending cards would do the job, but then a friend told me it doesn't work well.
I say "stack", but it's one of those thin card sleeve things that acts my wallet. Ideally, I'd be able to choose which RFID card to use simply by flipping over the card sleeve and tapping the desired card against the reader. Right now I have to remove the card from the sleeve and tap it by itself.
The internet tells me a piece of aluminum foil sandwiched between the offending cards would do the job, but then a friend told me it doesn't work well.
Response by poster: I'll try it soon. This only became a problem today, so this is a proactive question in case it's no good.
posted by spreadsheetzu at 3:54 PM on October 1, 2015
posted by spreadsheetzu at 3:54 PM on October 1, 2015
You're going to have to mask all of the problem cards, and ensure the one card you need is the first one in the wallet. This may end up being more of a colossal pain than just getting the right card each time.
posted by scruss at 3:54 PM on October 1, 2015
posted by scruss at 3:54 PM on October 1, 2015
1 - i have a wallet that is like two cardsleeves, joined in the middle. i put my (rfid) metro card in one side, and the others in the other side. then i swipe that side of the wallet.
2 - i've seen "wallets" that are two sheets of aluminium and a rubber band. here's one, but there are several. you could use an approach like that, with the card you want to use on the outside. edit: another, that explicitly claims to be rfid blocking.
posted by andrewcooke at 4:18 PM on October 1, 2015
2 - i've seen "wallets" that are two sheets of aluminium and a rubber band. here's one, but there are several. you could use an approach like that, with the card you want to use on the outside. edit: another, that explicitly claims to be rfid blocking.
posted by andrewcooke at 4:18 PM on October 1, 2015
Best answer: This is a common issue in countries that have progressed further than the US and Canada toward contactless payment (i.e. all the other countries). In the UK it's called 'card clash' and you might have some luck Googling that. Here's an article with some tips on how to avoid it.
posted by caek at 4:30 PM on October 1, 2015
posted by caek at 4:30 PM on October 1, 2015
Best answer: I wouldn't expect the aluminium to work well - generally it stops the tag on the front from working as well as the tags on the back, but still, if people say it's worked for them, give it a try.
My advice is to put as much distance (thickness) between the aluminium and the tag as you can using regular cards as buffers, eg: tag-card, mag-stripe-card, mag-stripe-card, aluminium sheet, tag-card, tag-card etc. because the closer the foil is to the tag's coil, the less signal the tag will be able to receive and send.
If you are unhappy with the results of the foil trick, something that has solved your problem for me every day for years is this.
It's an ultrathin tri-fold wallet, so it keeps a stack of cards just as thin as a sleeve does, yet unfolds as a wallet. As long as each pocket only has one RFID card in it, then you just flip it towards the RFID reader which will read the card that is now hinging away from the others. Plus, it's more functional than the sleeve (which is what I used to use) so even if the foil works, I'd still recommend it just for the added ease and utility.
posted by anonymisc at 4:39 PM on October 1, 2015 [1 favorite]
My advice is to put as much distance (thickness) between the aluminium and the tag as you can using regular cards as buffers, eg: tag-card, mag-stripe-card, mag-stripe-card, aluminium sheet, tag-card, tag-card etc. because the closer the foil is to the tag's coil, the less signal the tag will be able to receive and send.
If you are unhappy with the results of the foil trick, something that has solved your problem for me every day for years is this.
It's an ultrathin tri-fold wallet, so it keeps a stack of cards just as thin as a sleeve does, yet unfolds as a wallet. As long as each pocket only has one RFID card in it, then you just flip it towards the RFID reader which will read the card that is now hinging away from the others. Plus, it's more functional than the sleeve (which is what I used to use) so even if the foil works, I'd still recommend it just for the added ease and utility.
posted by anonymisc at 4:39 PM on October 1, 2015 [1 favorite]
The non RFID card should have no effect on the others.
Any distance between the cards should help including offsetting them. So try putting them on opposite sides of your wallet as well as in different compartments if you have them
posted by geekBird at 5:07 PM on October 1, 2015
Any distance between the cards should help including offsetting them. So try putting them on opposite sides of your wallet as well as in different compartments if you have them
posted by geekBird at 5:07 PM on October 1, 2015
Response by poster: Thanks for the suggestions so far. If the foil trick doesn't work, I will get a bifold or trifold card sleeve of some kind...I've got a rather long shortlist of those. :)
On my current card sleeve, I've tried using the non-RFID card and interior leather between my RFID cards to provide separation, but it didn't help. As it's a card sleeve with a capacity of 5 cards at most, my options for separation and offsetting are limited.
And yes, it's hard to Google this problem because I don't know the right term, and end up getting a bunch of results geared towards blocking RFID completely.
posted by spreadsheetzu at 6:24 PM on October 1, 2015
On my current card sleeve, I've tried using the non-RFID card and interior leather between my RFID cards to provide separation, but it didn't help. As it's a card sleeve with a capacity of 5 cards at most, my options for separation and offsetting are limited.
And yes, it's hard to Google this problem because I don't know the right term, and end up getting a bunch of results geared towards blocking RFID completely.
posted by spreadsheetzu at 6:24 PM on October 1, 2015
Best answer: These things are available in Japan (I actually have one from about 5 years ago when I lived there), and you can find them available from resellers on Amazon, but they have the import markup.
posted by that girl at 7:19 PM on October 2, 2015
posted by that girl at 7:19 PM on October 2, 2015
Response by poster: So the aluminum foil works, but only if I sandwich a non-RFID card between the foil and my desired RFID card. It won't work if the foil makes direct contact with my desired RFID card. Still, it has only been successful about 75% of the time so far.
I'll still explore alternate card sleeve options. The Japanese RFID blocking card is exactly the thing I originally had in mind as a solution to this problem. Can't get my hands on it in Canada, but perhaps getting an RFID-shielding card sleeve and putting it around my non-RFID card would be functionally equivalent.
posted by spreadsheetzu at 7:04 PM on October 3, 2015
I'll still explore alternate card sleeve options. The Japanese RFID blocking card is exactly the thing I originally had in mind as a solution to this problem. Can't get my hands on it in Canada, but perhaps getting an RFID-shielding card sleeve and putting it around my non-RFID card would be functionally equivalent.
posted by spreadsheetzu at 7:04 PM on October 3, 2015
« Older Multi-city USA low-key interesting-adventure time! | Avoiding the coke bottle look: do I need high... Newer »
This thread is closed to new comments.
posted by andrewcooke at 3:52 PM on October 1, 2015 [1 favorite]