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Who Needs a Satellite Dish When You Have a Wok?
An anonymous reader writes "Why pay $20,000 for a commercial link to run your television station when a $10 kitchen wok from the Warehouse is just as effective?
This is exactly how North Otago's newest television station 45 South is transmitting its signal from its studio to the top of Cape Wanbrow, in a bid to keep costs down."
If you'd actually read the entire article, which admittedly is a lot to ask, you'd have known that the local TV station used the same setup as an uplink, saving a cool $20.000
As long as you make it the right shape, there's no reason why a tinfoil dish wouldn't do the job too.
You should see how thin some dishes on real satellites are.
Donte Alistair Anderson Roberts - hi son!
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I think it's here :
http://www.usbwifi.orcon.net.nz/
The reflector does a couple of thing. The most obvious is that it catches the signal and focuses it on the antenna. The bigger the dish and the closer it is to a parabola, the more signal to the antenna. The other thing it does is to shield the antenna from noise. The antenna in the article seemed to be nested right inside the wok. So, the wok probably improves the signal to noise ratio (SNR) by at least double and maybe by a factor of three or four (or more if it's done right). That's very important. If your signal to noise ratio is good enough, you can use amplification to get the signal you need. If the SNR isn't good enough, then almost nothing helps.
The wok will give a useful increase in signal strength but a more significant improvement in signal to noise ratio.
This is in New Zealand... we're a little different to America
It was Slashdotted in the past...
o n.net.nz/
The links to part of the sites covering it are:
http://www.usbwifi.orcon.net.nz/
http://www.stanford.edu/~jstockdl/tmp/usbwifi.orc
I am not merely a "consumer" or a "taxpayer". I am a Citizen of the State of Texas
Yes, woks can be good enough approximations of parabolic cross section. /. have featured a few time ago an article about using wok colanders as dishes for Wifi USB dongles, and a several techniques to check is the parabolic approximation is good enough.
/. article " 4km WiFi Range w/ $5 DIY Antenna ". TFA is mostly the same idea but applied to a different signal in the same GHz range (microwaves).
And in fact, because of the wave-leght of TV, WiFi, Bluetooth, etc.. (signals in the GHz range have centimetric wave-lengths) their corresponding colanders too can be used as cheap antennas, and have the aditionnal benefit of having holes (they are basically metallic mesh) and therefore having less friction against winds (and lower risk of being blown away during a storm).
- one technique, which can be done in the shop before buying the colander, is to use a small chain whose shape when suspended at both end and check if shapes match (checking if the shape is "catenary")
- another is to cover the colander in aluminium foil and checking if a parallel light source (the sun) converge to one single point (where the USB dongle should go once everything assembled)
See
"Sufficiently advanced satire is indistinguishable from reality." - [Tips: 1DrYakQDKCQ6y52z6QbnkxHXAocMZJE61o ]
This is the effect you see with thin foils in a microwave oven, and has led to the extremely popular misconception that you can't put metal into a microwave. With a minimal bit of observation anyone will see that the entire microwave enclosure IS metal and reflects the microwaves just fine without significant absorption. The only problem is with thin foils which are incapable of efficiently reflecting the microwaves.
I haven't calculated how efficiently tin-foil might reflect the high power radio waves mentioned here, but wouldn't put money either way without checking. (I haven't yet read the fine article, so I don't even know what power levels we're talking about).