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A buddy of mine used to make money by going to houses that had unsecured wireless networks, explaining the risks, and charging them $25 to turn on encryption. The hardest part is figuring out which house belongs to a particular network. He said he used some little handheld device with a semi-directional antenna and a signal strength indicator, I imagine something like

I'm considering trying the same thing, but I don't want to buy that device; I'm sure the same thing can be done with my laptop. I bought a super cheap USB WiFi adapter with a place to plug in an external antenna, then I made myself a "cantenna", but when I use it with NetStumbler, pointing the can in different directions doesn't seem to give me significantly different signal strength readings. Possibly because my little USB device is super cheap?

Is there a better way to determine the source of the signal, or am I on the right track and I just need to tweak/invest more?

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closed as off topic by jscott, GregD, Chopper3 Nov 10 '10 at 21:22

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-1 for ripping off people who don't know any better – Ben Pilbrow Nov 10 '10 at 21:18
Yikes, you think? That's not my intention. It seems like a legitimate service that would make neighborhoods safer. Perhaps my friend's $25 is steep, but I don't think concept is wicked. – Trevor Nov 10 '10 at 21:21
How does it make the neighborhood safer? – joeqwerty Nov 10 '10 at 21:30
More, like, "I work for an alarm company, I noticed you don't have a little sign indicating that you have a home alarm, can I sell you an alarm?" (You wouldn't want to actually connect to their network.) – Trevor Nov 10 '10 at 21:40
lol, the question is closed. What can I say.. possibly, a length of cantenna does strips off a noise (radio comms, tv, cellphones) only. Get a longer wave carrier, something between 80cm..1.5meters – kagali-san Nov 11 '10 at 3:20

I would use my iphone :D But your basically needing a directional antennae to make your work a little easier.

Your on the right track i would say.. However it sounds like a lot of effort for $25

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+1 for the answer and comment. I would think that the effort it would take to get over the automatic mistrust people will have when you show up at their door would definitely not be worth $25. – Andrew Barber Nov 10 '10 at 21:23

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