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Whoa whoa! If you're saying Atheros broadcasts too far, what would the FCC say about my two Hormel Chili cans soldered together, artistically painted and decorated, with a confirmed distance of 5.1061 miles.

I don't know if this is the case. Everyone seems to assume you can "intercept" the RFID information from many meters away. I guess I'm not sure which technology is used in credit cards, but if it's anything like ISO 14443 standard or even ISO 15693, the max distance is only going to be 1.5 meters or less.

Anyone stating "max distance" for RF is creating limits where none exist. With a correctly-sized transmitter, a sensitive enough receiver, and a large enough antenna, there's nothing preventing reading over much greater distances.

The "hacker" world distance record for reading RFID tags (not necessarily the same technology that's in these credit cards) was set at Defcon in August 2005. It was 69 feet, or over 21 meters. You can see the Make Photo Blog pictures of the gear used. While the kit may look bulky, 69 feet would allow you to have it in a van parked outside a store shooting in through the windows.

Regarding the correctly sized antenna, the WiFi shootout that year scored a record 125 miles for an unamplified 802.11 link. 125 miles from a pair of hundred-milliwatt transceivers chatting at 11 mbps.

And don't assume it's not worth the trouble, either. You don't know what dollar values may be transacted via RFID, nor what thefts may be possible with the intercepted data.

That's not to say that encryption isn't capable of rendering the data useless to an eavesdropper. We don't know if it is or isn't good encryption, but that's immaterial. Don't rely on distance alone to protect you. It won't.

Yes, ham radio exists and has lots of new high-tech directions. Unfortunately, for the /. crowd (and even more for the general Internet community), there are limitations to what you (we) can do in ham radio compared with the Internet.

Amateur radio is a licensed service, meaning that a non-trivial (though pretty easy for /.-ers?) exam is required. This will always keep out the general public -- either a good or bad thing depending on point of view. Some folks would like to see licensing diluted to the level of Citizens Band or GMRS, i.e., widely ignored and no technical content anyway, but most hams want to keep up a reasonable entry barrier to ensure some level of motivation and technical and operational competence.

The other point is that the amateur radio service is by law non-commercial, meaning that no one can be paid for providing communications services. There is some debate whether you as an individual ham are allowed to "order pizza" (or use Amazon.com?) using your own radio. Certainly, no business could use the amateur bands. That rules out a very big chunk of Internet traffic.

A lot of computer experimenter work uses WiFi technology - which is an unlicensed mode without the ham radio restrictions. (WiFi frequencies overlap a ham allocation, so you can use WiFi gear as part of a ham licensed network if you want.) There is some neat extreme ham-like WiFi.

With my ham station, I can routinely communicate digitally around the world at 31 bps (keyboard to keyboard)and 50 watts of power, even at sunspot minimum. No ISP, no infrastructure dependencies! It's a gas.

Further reading at www.arrl.org and Wikipedia.

-Martin, AA6E

With the cooperation of someone in-town who has broadband (or can get it), you could rig something like this. I had been considering something like this before I decided to move. A bunch of work, and a bit of equipment, but I'm sure with your broadcast engineering skills it wouldn't be a problem. There were teenagers that won this contest a couple years ago at 55 miles, with satalite dishes that they obtaind for free from neighborhood homes that didn't use them anymore. Fun stuff.

That's amusing... I was just thinking to myself, "yeah, but if you're stealing someone's bandwidth from 125 miles away, how are they going to catch you?" Then I looked at the picture.

Does anyone else remember seeing that? I can't seem to find a link.

Sure, here it is. Scroll down for pictures.

Will we see this at next year's WiFi Shootout?