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Quick and dirty USB wifi dongle waveguide

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Picture of Quick and dirty USB wifi dongle waveguide
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This is a five minute fix to stealing neighbour net, it's not that pretty but it's simple and rather effective, plus it's fully adjustable for angles of up and down, not just side to side. 

I haven't bothered with Db gains because if you're serious enough to care about them then you've got the wrong waveguide, this will however take a just out of reach network and make a decent connection possible. 

Disclaimer - This project involved stabbing things with sharp things to make more sharp things, the edges of the can can be very sharp and I cannot be held responsible for any damage done to yourself, those around you or any passing badgers. 

If you liked this instructable then please vote for it in the USB contest, which is in the voting stage now!
 
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Step 1: Tools and Materials

Picture of Tools and Materials
There's not much to the list, you'll need:

Materials:
 - Gorillapod, glue, a stick, a piece of string, you don't have to mount it on the gorillapod but my camera's too heavy for it so it was unused and I planned on doing some hunting for the best network so adjustability and stability are nice
 - A USB dongle, the stick kind, if it has an external aerial this would still work, you could also slide the can over any stick aerial to direct it I suppose. 
 - Some tape, electrical tape or anything thick works, I used awesome caution tape.
 - A sweetcorn can, they're fatter, though the large size bean cans would also work well

Tools:
 - Knife

Optional tools include any nicer way of cutting holes in cans, me I just got stabbin'

Step 2: Start Stabbin'

Picture of Start Stabbin'
Cut your can in half, down the sides, I left the top ring of the can since it makes it more rigid and leaves one less sharp edge. 

If you want to remove the reinforced top ring some cans have then a pair of pliers or snips will make short work of your ring... 
yogy20203 years ago
It's work with me thank you so much.
I am using coca cola can. And it's funny :)
I was have 20% signal strinth But NOW I have 39% :)

الحمد لله هذه التجربه إشتغلت معي
إستخدمت علبة كولا
وزاد البث
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killerjackalope (author)  yogy20203 years ago
That's awesome, thanks for posting a pic too.
You welcome :)
legless3 years ago
If you have a Dremel and a thin cutoff disc it will make short work of a can and the edges will be far less jagged and there will be less blood. LOL.
I just made one of there, but i dont have one of the tripods, but i used a dremil with the smallest blade i had and i just covered the edges with a tiny layer of gorilla glue xD
killerjackalope (author)  legless3 years ago
Amost certainly true, unless you have some extreme skills at fail
StuNutt3 years ago
Nice, simple antenna! Couple of suggestions here though:- You don't need the top of the can to be open, so try a coffee tin, large as you like (!) and re-fit the lid after you've finished. (Larger can will give more gain)

The cylindrical body of a large soft-drink bottle or similar could be used to make the whole thing "prettier" but also make safe those sharp edges. Leave the bottom on the soda-bottle and fit it over the can with the base at the top of the assembly, and the cylindrical part of the bottle extening well beyond the bottom of the assembly, as a "skirt" to keep the rain out and make it usable outdoors.

With the antenna outside of the building you will get a much better signal.

I have my wireless access point near the front of the house (because that's where the cable enters), and my ham radio shack at the bottom of the garden, and the signal is not bad, but could be better. With this on the roof of the shack, I think I'd get the full Wireless G throughput - and also maybe help to avoid any interference from the WiFi on my ham band reception.
killerjackalope (author)  StuNutt3 years ago
The tops open because the can was opened, no other reason, its a good point to mention that it doesn't have to be. The idea of making the design a bit safer and tidier with bottle is good though adds a little complexity, I reckon for the roof a big coffee can might work well for weatherproofing and would probably remove good chunk of transmission interference as long as the can was directed away from the antenna.
ediz3 years ago
Could I use a Pringles container? It would be easier and safer to build.
legless ediz3 years ago
Actually there are plenty of Pringles "cantenna" designs out there on the net. Both external versions and reflector ones like this.
killerjackalope (author)  ediz3 years ago
I suppose so yeah, though it'd be tricky to stop falling apart on being cut up...
botnot3 years ago
digame mas del (the cone). botnot
botnot3 years ago
It is a ! botnot
botnot botnot3 years ago
sorry, I meant "it Is a reflector!" botnot
killerjackalope (author)  botnot3 years ago
Que?
botnot3 years ago
mande?
botnot3 years ago
Hi, For the edges of the can, one can get some model airplane clear fuel tubing, (or similar 1/8" or 3/16" diameter rubber tubing), slit it on one side and glue it over the rough edges. Also a slit can be cut in the bottom and the usb adapter slid to various distances from the apex to fiddle with the sensitivity and power. Also, a 'square can' offers a wider aperture and may pull in more signal strength. botnot
killerjackalope (author)  botnot3 years ago
Hmm, good points I like the idea of making an adjustable one. It's a little more complex that this one but definitely worth a look in, though I suppose the slot and some blu tac would give it adjustability and still be simple.
Actually, I usually use an adapter, (or a 14 dB antenna), free standing on a flat surface and then fold foil maybe 2' x 1'. I fold the edges over in 2 1/2'' folds on all 4 sides for rigidity, and then fold it vertically in the middle of the long side and set it on the surface. I use about a 135 degree opening and can just slide the foil to adjust the gap. I have also glued foil to, (for example), the cardboard back of a desk calendar and bent it to 135 degrees. I can aim these easily and fudge the adapter/antenna location easily. I also used a gorilla tripod and the lid of a large coffee can for a surface and worked off that. I like your can idea as it is rigid and stronger. Right now I have internal laptop wifi and don't need the adapter, so I am not using reflectors. If you haven't, check out www.seattle-wireless.com for wifi antenna and reflector ideas. Also google or . I have never seen an arrangement like yours, so it is very creative and unique to me. By the way, Engenius and Ubiquity have infinitely stronger wifi adapters and they are not too expensive. I get a huge signal gain with engenius. The power is very high for pc or laptop, and reflectors make it all the stronger. thanks, botnot.
killerjackalope (author)  botnot3 years ago
Ah this standard cheap adapter's fine for my purpose, I actually have another design as well, I'll post it up because it's a much more powerful one but impractical and very silly looking. Basically a cone for dongles that requires no thought or care, takes minutes to make and is pretty forgiving.
wsgraham3 years ago
Good job. It doesn't have to be pretty to work and it sometimes doesn't even have to be 100% spot on to get the increase you need. Parts list should probably include band-aids. As an alternative, you could encourage your WiFi transmitting neighbor, I mean "provider" to fab up something like this to boost THEIR signal. http://cellar.org/showthread.php?t=22228
killerjackalope (author)  wsgraham3 years ago
They live down the street and have a certain disdain for me that may cause trouble persuading them to do so. I've had a whole ton of different things to boost the wifi signal but this one's the one I always come back to because it's so quick to make and much less sensitive to being out by a bit when it's made than a traditional cantenna...
rimar20003 years ago
Killerjackalope, you can multiply the signal strength bringing closer to the rear tin the dongle. More precisely, at half of the tin radius.
Please see http://farside.ph.utexas.edu/teaching/316/lectures/node136.html
You need an "L" at the end of he string. http://farside.ph.utexas.edu/teaching/316/lectures/node136.html
killerjackalope (author)  rimar20003 years ago
You're right on that score, however for a rough project and a general use waveguide the middle works more reliably. Bringing it backwards makes it much more sensitive to change and alignment.
That's right. The focus of a spherical concave mirror (in this case cylindrical) is located halfway between the reflecting surface and the center of curvature. If the issuer is in focus, the reflected beam is parallel in theory, that is with zero dispersion. But being in the center of curvature, the dispersion is too large, 180 degrees. I would try an intermediate option, pulling up the transmitter to the bottom of the can. I hope that my "machine translator English " be understandable.
killerjackalope (author)  rimar20003 years ago
You're right there I'd say you'd get a range increase without too much trouble at two thirds of the way between the centre of curvature and the edge. That said as long as it works, this is a very rough science free one and so far it seems a wider can and the dongle near the centre is most likely to work...
botnot3 years ago
Oops, I forgot. REI in the states sells the Gorillapods cheaply in various sizes. botnot
nickodemus3 years ago
Nicely done! As a fix to sharp edges, some aluminum tape would work great.
killerjackalope (author)  nickodemus3 years ago
Yeah, even electrical tape would do, cheers for the tip.
Scott_Tx3 years ago
From the look of it I'd say its more of a reflector than a waveguide
killerjackalope (author)  Scott_Tx3 years ago
It does also reflect the signal as well, so I'm not sure which is the more accurate name for it, the over simplicity of making it, lack of sums and more just straight experimentation probably means that both qualifications are way too technical to be accurate for this thing.
Allows packets to be sent as well as recieved.
killerjackalope (author)  Yerboogieman3 years ago
That it does, probably the best explanation for that argument...
omnibot3 years ago
Nice one, a useful and simple design, not to technical and threatening to a beginner.
killerjackalope (author)  omnibot3 years ago
I've went through several iterations of this particular design, different cans and different ways of putting it together, basically getting lazier or, or, more efficient each time...
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