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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.
There was a story about freecache, but no one here on slashdot ever uses it in stories. Here's a pre-cached link, in case the main NZ server goes up in smoke. http://www.freecache.org/http://www.usbwifi.orcon. net.nz/
General Tso's Access Point.
The only acceptable defense of scientific results is to say that they were the product of the Scientific Method.
it has other uses as well. If you wrap your head in this spider silk mesh it is even more effective at blocking the evil thought control waves than tin foil!
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.
I guess 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).
Am I part of the core demographic for Swedish Fish?
It couldn't possibly be omnidirectional. That would break the laws of physics. To get a boost in signal strength you must either make it more directional or increase the power itself with an amplifier.
"Studies have shown that people who eat peanuts live longer than those who do not eat."
http://www.stanford.edu/~jstockdl/tmp/usbwifi.orco n.net.nz/
...
Mirrored as much as I could of the images before the server was smoked.
-S
**AA: a bunch of mindless jerks who'll be the first against the wall when the revolution comes
Good to know some people are still trying to improve technology remembering that not everybody has 1 trilion dollars a month to spend on over-priced gadgets.
Good work!
Piece of number eight wire reputation.
Hmm, now I feel sadly parochial.
In theory for a transmitting antenna, there is no limit to how much gain you can get. Gain is the ratio of received power to the power you would get with an isotropic radiator. To get gain, you just focus the beam tighter. The limit to how tight you can focus the beam is set by the aperture of the antenna. The gain of a receiving antenna is set by its effective area. Gain isn't hard to get.
The bigger problem is to get line of sight. At this frequency, if you can't get line of sight, all the gain in the world won't help.
"Omnidirectional" is somewhat of a misnomer. Omnis transmit a pancake-shaped signal -- good signal in all directions in the same plane, but very little signal up and down. What you're refering to is called an isotropic radiator.
-jim
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.
"Chinese parabolic cookware"
OMFG is that funny.
- Zav - Imagine a Beowulf cluster of insensitive clods...
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
Why can't we break the laws of physics?
If he is getting that kind of gain from the scooper, imagine if he used the wok...
The device is putting out the radiation... No matter antenna you put on it you don't increase the output of the device. Now you do focus it into a much "hotter" spot when you make it directional. Even so though none of these devices are allowed to excede 1W of effective radiated power (No commercial consumer device currently excedes 250mw).
:}
:}
To give you an example... You microwave uses 4000 times that much power to cook food with.
I would imagine if you stood in the beam path of a 20+db antenna for a couple months you would have health issues... but you also wouldn't have a signal
As health risks go a cell phone is a MUCH larger output of power and you stick it right next to your head. Worry about those first
And FWIW cantennas are no better... most directional antennas send most of their power out the front but all of them have sidelobes.
Telcos have alot of dark fibre in the States. Most people assume that's optical fibre...but it's actually moral fibre.
Once you've connected to the network, you'll just need to connect again in an hour or two.
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... :-)
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I didn't shop around for best price, etc, etc, 'cos I knew that once this thing hit slashdot, there was gonna be a worldwide stockout on the chinese cookware. I could have gotten things a bit cheaper if I had shopped around, but short of an AUD$1200+ aeroplane ticket to Guangzhou and buying direct from manufacturers, there was no way this setup would cost $5.00 of anyone's money. With time and petrol and driving around, I guess it cost AUD$100.00. Good fun tho, and worth every cent.
I find your ideas intriguing and I wish to subscribe to your newsletter.
Actually, a lot of products have really long ranges -- right out of the box! I got a Linksys WiFi router and it seems like I can pick up my SSID "linksys" network all over the place!
Heh heh..