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DefCon WiFi Shootout Winner Announced
devn2k writes "At the first annual WiFi Shootout at DefCon in Las Vegas, Adversarial Science Lab won the contest to shoot a wireless signal across the Nevada desert, with a distance of 35.2196 miles. The antenna was built from metal poles, window screen mesh, cardboard, duct tape, and aluminum foil! According to the official contest page, the antenna was designed the night before the contest, its component parts were purchased for $98 at Home Depot, and the next day it was built completely from scratch in the desert, on the side of the mountain, in the rain."
Damn, I guess for US$98 you *can* change the weather :).
You forgot to add "...while walking uphill, in a blinding snowstorm..." followed by the obligatory "... and we liked it!".
I'm sure their success is attributed more to knowing what you are doing in a McGyver'ish way than simply hacking.
:)
That special knowledge that is the difference between the guy who buys dirt for a garden versus one who knows what to plant and mix in to make soil healthier.
Yeah, anyone can make a bomb with the proper chemicals, but can YOU do it with bubble gum, a piece of thread and a muffin?
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ping -f 255.255.255.255 # if only
Nobody expects the Adversarial Science Lab! Our main construction material is Metal Poles!
Metal poles and Window Screen Mesh!
Two construction materials! Our Two Weapons are Metal Poles, Window Screen Mesh, and Cardboard!
Our Three Main Construction Materials are Metal Poles, Window Screen Mesh, Cardboard! And Duct Tape!
Among our CHIEF building materials are such diverse materials as Metal Poles, Window Screen Mesh, Cardboard, Duct Tape, and Aluminum Foil!
Oh, bother. I'll come again.
Edward@Tomato - /home/Edward/ man woman
man: no entry for woman in the manual.
"Qua!?"
Notice that the shape of the winning antenna is a pyramid? There are a lot of theories regarding electromagnetism and the pyramid shape, including a bunch on how the ancient egyptians figured out how to utilize these electromagnetic properties, which is (supposedly) why the pyramids were built that way.
If you want to get kooky, it can also point to the extra terrestrial origins of ancient egyptian civilization.
Why do I h8 apple?
Alvarion is not Swedish (in fact, it's basically BreezeCom in new clothing), but the record was set with the help of SSC, the Swedish Space Corporation. Slashdot story link here.
Money for nothing, pix for free
Photo of anntena and team. Its look pretty cool.
-- ladies and gentlemen we are floating in space!
Easy!
You eat the muffin, stick the bubble gum over your rear end and fart until you have a nice big bubble full of explosive gas. You then poke the bit of thread into the bubble to act as a fuse. Done and ready to light.
Whilst the homemade winner was pretty good, im a bit suprised by some of the commercial entries.
eg: "Using a Stock Hyperlink 15dBi Omni at the base camp, and a stock Hyperlink 24dBi parabolic grid at the field site, with a confirmed distance of 10.1625 miles"
the WAFreenet (Perth, Western Australia) has several links of 18 to 22km (11.25 to 13.75 miles) - 30mW Clients with home modded 24dBi dishes (galaxy mods), connenecting to a 30mW AP with 14dB Waveguide. These links are about 8 - 10 SNR IIRC.
Our best is a link to the same AP from Rottnest island - 46 km! One connection was using an ipaq + cantenna with 2SNR, and another was with a modded satellite dish (overpowered at about 40dB EIRP), not sure of it's signal performance.
Several groups in the eastern states of Australia have achieved similar resulst.
If I only got 16km with a commercial 24dBi panel, i'd ask for my money back!
NASA scientists make fun of Slashdot users for unit conversion errors...
People (ahem) were flashing the firmware on their Senao cards to enable them to go up to 249 milliwatt. The entire area was bathed in 801.11 frequencies. Shit, I felt my hair stand up.
It was funny to see a thousand black-clad geeks waving their WiFi antennas in the air, trying to get a signal. If you didn't know better you would have thought it was some kind of dildo festival.
I'm sure their success is attributed more to knowing what you are doing in a McGyver'ish way than simply hacking.
Yeah, antennas don't respond well to guesswork.
Most people don't know that an antenna rings electrically the way a tuning fork rings mechanically. There's only a very limited frequency range that an antenna will handle well.
On top of that, as the frequency increases, radio waves behave more and more like light. And problems like stray capacitance and stray inductance - tiny values in farads and henries - become very important design considerations as the frequency increases.
But a well-designed amateur antenna can be very capable. The radio waves don't care if you make the elements out of silver encrusted canine feces, if they're the right lengths.
UHF TV band, around 450MHz. Design is extremely critical here. But by doing a little math first, I designed and built a 12-element Yagi (looks like an ordinary rooftop TV antenna but with more elements) which is tuned to channel 29. It's very directional, meaning I have to be pointed within a few degrees of the transmitter. But I can also watch WUTV Fox 29 from Buffalo, in Ottawa Canada, without shelling out for cable. Cost? Scrap of wood, old coat hanger wire trimmed to within 1/16" of the design dimensions, plastic tubing and clips to hold the elements to the board, old 75-300 ohm matching transformer gutted for its balun and soldered directly to the driven elements and feeding coax. Essentially free. Not waterproof, so it lives in my attic.
Fire and Meat. Yummy.