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Wireless-Friendly Microwaves
Makarand writes "According to this article on ABC News, scientists at the University of Michigan in Ann Arbor have stumbled upon a simple and elegant solution to keep your kitchen microwave from
becoming a noisy nuisance to your home Wi-Fi network.
They found that they could focus the microwaves into a single frequency and
reduce noisy
microwave emissions by placing ordinary magnets in specific patterns along the magnetron .
New techniques to reduce microwave interference will be needed when
Wi-Fi enabled entertainment systems will allow digital audio and video to be transmitted
to different rooms of a house wirelessly. Packet drops in such a sytem would degrade the video and audio
experience."
Low-noise microwave magnetrons by azimuthally verying axial magnetic field - here
$ strings FTP.EXE | grep Copyright
@(#) Copyright (c) 1983 The Regents of the University of California.
I have big problems with the radio that the CIA implanted in my brain.
They found that they could focus the microwaves into a single frequency
...
Why not go all the way and make the frequency and phase of the microwave oven's magnetron adjustable, add some kind of microcontroller to drive it, and a small cpu to implement the 802.11b stack. Then, from your laptop, run this script:
WIFI_IF=eth0
DATE=`date +%s`
while [ ! $TIMEOUT ];do
DATE_PREV=$DATE
tcpdump -i $WIFI_IF -c 1
DATE=`date +%s`
let TDIFF=DATE-DATE_PREV
if [ $TDIFF -gt 5 ];then
TIMEOUT=1
fi
done
echo "Coffee is hot!"
Ah, the marvels of technology
"A door is what a dog is perpetually on the wrong side of" - Ogden Nash
Probably because the magnets have to be placed inside the microwave, close to the tube....and one doesn't want the average consumer messing around in there...
More like be prepared to be booted as the microwave will cut off 802.11b. I did not have a problem with this until I bought my current microwave (it's a bit closer to the AP then the old one was). When ever the microwave is on, the signal drops to zilch and I disconnect. Makes me wonder how safe these things are! :)
Gorkman
legacy microwaves
Now there's a phrase you'd only hear on slashdot.
Remember, it takes 42 muscles to frown and only 4 to pull the trigger of a sniper rifle.
When you hit water with it, it will agitate the molecules and things get hot and cooked
You seem agitated and cooked enough without microwaves.
The difference is in power and concentration : a microwave oven is minimum 700W, concentrated on a lump of water, whereas an 802.11b is 100mW radiated in all directions. You'd need hundreds of wifi cards doing denial-of-services around a cage to even start incommodating the hamster inside.
"A door is what a dog is perpetually on the wrong side of" - Ogden Nash
2.4 GHz is not the resonating frequency of water. That's way way up in the GHz chain. 2.4 GHz was chosen because that band is the junk band in which unlicensed users are subject to interference as part of the spec.
Microwaves work by oscillating water molecules, which are dipole. The magnetron cycles 2.45 billions times per second, which twists the water molecules. The interior of a microwave oven is coated with a microwave-reflecting material which allows a single beam to essentially paint the three-dimensional interior.
So many people write that water resonates at 2.4 GHz. It's just not true. Here's a nice explanation of how it works.
Freelance tech journalist for the Economist, MIT Technology Review, Macworld, and others