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4km WiFi Range w/ $5 DIY Antenna
Mignon writes "This industrious fellow in New Zealand made his own WiFi antenna using a USB WiFi adapter and a Chinese 'spider skimmer mesh scoop.' He got about 17 dB signal improvement for about US $5 in materials." Update: 05/25 23:09 GMT by T : Reader
John Stockdale offers a U.S. hosted mirror of the site. Update: 05/26 13:58 GMT by T : Reader Jared Mauch contributes another mirror.
I wonder if there are hidden shortcomings to this technique. If it only costs $5, I would think that manufacturers of wireless access points would have implemented this a long time ago (or at least made it available as a $40 add on). After all, there *is* a market for it, and at least some people would buy such a device.
Actually, I cached it before the story ran because I saw it before it went public (subscriber), but the problem is, if the server goes up in smoke, freecache will stop serving because it can't verify the server is still there. That was my mistake. We need to use freecache in the actual story, rather than in comments, I guess.
Good point about the file size - html != >5MB.
I lived in Wellington, New Zealand for a while, and I sure hope this guy is using this to steal access from somebody else, not to share his bandwidth with other people. Internet connectivity was very expensive down there, and metered (we had dsl through Telstra). Even the much-hyped CityLink wireless service is pay-as-you-go. But with his $5 setup, this guy can scan around his neighborhood until he finds somebody with an open network, and presto! Free 'net access.
Iguess it's a neat hack if that's the only way to communicate with your friend 4Km away, and you only have one friend (or your one friend has a nice network connection to the rest of the world and is willing to share).
An acquantance of mine is considering setting up something like this, since he can't get high-speed internet access -- too far for DSL, and the cable company hasn't upgraded his section of the network yet. However, a five-mile wireless link would let him work off someone else's high-speed connection -- it's just a matter of finding someone willing to help.
"They redundantly repeated themselves over and over again incessantly without end ad infinitum" -- ibid.
The airport base station doesn't have a range anywhere NEAR 14km. There are lots of antenna out there for lots of base stations (including the Airport ones) that will give you that range, but Apple has not "had this for years" any more than every other vendor that sells products with the option of adding an antenna.
Hell, Cisco has products that have 25 MILE ranges, with the right antenna.
My sig is blank, I typed this by hand.
I just took a long car trip, relying mostly on (purchased and municipally provided*) 802.11 access, and in preparation for that trip bought a highish-end 802.11 card and extrernal patch antenna, which indeed came in handy.
:)
I considered one of the USB 802.11 donglers, but passed on account of ignorance: Are any of them of Linux-friendly? Are some brands better than others? Can anyone provide reception figures or anecdotes?
It certainly would be nice to have a rooftop mount on my station wagon to which I could as necessary string up a 15' USB cable and thumb-drive-style 802.11 thing
timothy
*Thanks, taxpayers and politicians of Salt Lake City!
jrnl: http://tinyurl.com/c2l8yr / foes: http://tinyurl.com/ckjno5
The antenna is directional so this kind of range isn't that helpful unless the two end points are stationary.
Wrong. It isn't helpful unless one end point is stationary. Which is a big difference.
Case in point. I live on a fairly large property. I'm trying to extend my wireless signal to the edge of the property, where my hammock is, so I can work in my hammock. A directional antenna hooked to the transmitter on my router inside my house extends the range in whatever direction I point the antenna in, i.e. towards my hammock. Since the antenna increase pickup as well as transmit power, I just put it on my stationary router, and I don't need to do anything to my wi-fi card on my mobile laptop.
If I wanted to extend coverage to the whole property, I could aim my antenna at a distant repeater to get omnidirectional coverage from the repeater, while still increasing range from my base-station router.
Wireless rules.
I moderate "-1, Fool"
Of course different areas have different rules, but just about everywhere there are restrictions on antenna gain and power for 802.11. Especially if you are not a licensed amateur radio operator.
These things are unlicensed part 15 devices which have strict restrictions on power output (which includes any gain from directional antennas) and can not interfere with licensed devices like amateur radio operators.
I'll leave it up to the reader to Google for what the limits are in your area since it varies. Just remember that you can't just slap on any super-high-gain antenna and remain legal.
The ratio of people to cake is too big
Not political dangers, not legal dangers, but health risks. This is an unshielded piece of metal that's surely producing signal all over the place. Wi-Fi is microwave radiation. While it's not a big deal for the tiny antennas in cards or bigger antennas that are found on access points, when you start boosting the gain and have directional focus, it's critical for your long-term well being to not spend extended periods of time (or, for higher-gain antennas, any time whatsoever) in the "blast" of the beam. There are well-documented health risks from microwave radiation exposure but only at high levels and short distances.
Because this ad hoc device hasn't been checked out in any fashion, it's possible that even with it facing away from you, you could be subjecting yourself to cellular damage from the microwave radiation. I wouldn't recommend this. The cantenna design is much simpler and safer. Other ad hoc designs at least have parameters that prevent so much signal spew. This one worries me.
Freelance tech journalist for the Economist, MIT Technology Review, Macworld, and others
I was wondering why your post was informative rather than funny until I checked the link. The original Cantenna (Heathkit?) was a paint can filled with transformer oil and a 50 ohm resistor dummy load for tuning transmitters--not much gain there! :^)
One line blog. I hear that they're called Twitters now.
Bluejack
I already built one of these things after the site first surfaced a couple of weeks ago. The neat thing about it is that it's modular insofar as your choice of radio goes. Unplug the 802.11b tranceiver, replace it with a usb Bluetooth tranceiver, aim at the nearest bus stop, and wa-la, bluejack city. Want to use 802.11g, or heaven forbid, 802.11a, plug one in! It's the ultimate in modular l33+ hax0r radio toys. Why, I reckon you could even plug an usb IrDA adaptor in there...
No, wait... :-)
I find your ideas intriguing and I wish to subscribe to your newsletter.
Since old dishes are about free, how about replacing the LNA with one of those same sort of external wifi transceivers?
Anyone try such a thing?
---- Booth was a patriot ----
Would an old satellite dish work for this? I notice that DirecTV dishes are quite shallow, so would this be a problem.
You can get a used DirecTV dish pretty cheap.
I can't believe it! I work at the chain (DSE - dse.co.nz) that the mentioned WiFi adaptor came from (It's a Zydas that we rebrand).. In fact, I work at the branch on Vivian St, Wellington where Stan (one of the guys involved) actually bought those.. One of our best customers.
/. :)
Never thought I'd see something local on