Instructables
Now that you have finished drinking that last tasty cup of coffee, what do you do with the empty coffee can?

Go Wireless! That's what.

Here is an easy to build, accurate and powerful wireless antenna made out of an empty 13.5oz coffee can. Some soldering experience is required to build this project but if you can wield a soldering iron and a roll of solder, you can't help but turn out a well built antenna for long range wireless communications.
 
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Step 1: Parts and Tool List

Picture of Parts and Tool List
To enjoy great wireless, you will need at least one antenna. If you are planning to create a short haul project between two locations, make two antenna so you have a matched set.

Parts List

1) 13.5oz Maxwell House or any other brand tin can with plastic lid. (Empty of course).
1) 4 inch by 4 inch sheet of brass or tin.
1) 1 inch long by 1/4 inch diameter Brass tubing. (Any model or hobby shop).
6) feet of AIR195 low loss 50 ohm coaxial cable. (Available from air802.com. RG-58 may be substituted with marginal results).
1) SMA Female connector. (For connecting to your bridge or antenna jack. Available from air802.com)
1) Brass angle bracket. (Local hardware store).
1) 1/4-20 Brass hex nut. (Same hardware store).

Tools Needed

30 to 50 Watt Soldering Iron
Silver Solder
Solder Flux (zinc chloride or rosin type. not acid flux)
Coaxial cable connector crimp tool for 1/4 inch cable.
Drill with assorted drill bits
Black spray paint
RTV Silicone Rubber compound or Clear Silicone Bathtub Caulk
Sheet metal sheers
File
Sandpaper
'0000' Steel wool
greatromeo11 months ago
Good
tiffanymj1 year ago
is there anyone that i could pay to be build me one these awesome extenders. i don't have ANY of these kinds of tools at my house. any takers. quote me a price....
old_alex1 year ago
In the early 80s HBO was broadcast to homes via 24GHz line of sight. I built a coffee can receiver (added a yagi antenna later). Had a phase lock loop to lock in the frequency. I think it was the first time my buddies back home didn't think of me as one of their dumb beer drinking buddies. Richard Prior, Ghost Busters all from a coffee can with a few electronic parts, hanging out the upstairs window.

In the mid 80s is when HBO started suing people for it, somehow their signal beamed onto your property without permission was still their property. Big money ruled out squashing creativity. This was one of my first real hacks, legal until they changed the rules!

The Yagi was a work or art, a brass rod with metal roofing disks soldered to it. I threaded at the end of the rod passing through 2 nylon disks for support, done to adjust the distance between the end plate and the receiver for optimum gain. This was when I knew something about analog, those days are long gone, not even a picture.

Here is link of what happend when someone tried to go commercial with the hack. Coffee_can_HBO_CRACKDOWN


T
hanks for the memory!
acastevic4 years ago
nickvader5 years ago
Can I replace the cable with an Ethernet cable to plug unto my computer
 where i need to join the cable that gose in laptop??
 NO..... the cable is not shielded, has too many conductors and is the wrong impedance...... This needs a to be a shielded coaxial cable.
betito4u5 years ago
how much gain this cantenna has ,and how far is that?
burningsuntech (author)  betito4u5 years ago
betito4u I haven't calculated or measured the gain. Lately haven't had much time to do structables. Busy working to stay out of debt. Thanks for asking. Raving apache
sounder5 years ago
Do you think additional gain could be achieved by incorporating a full wave rather than a 1/4 wave element such as described in the attached instructable ?

http://www.instructables.com/id/WIFI-Antenna-Hack!/?embed=flash
burningsuntech (author)  sounder5 years ago
sounder Perhaps. The antenna was built tuned to 1/4 wavelength. How do you intend to measure the increase in gain? raving apache
burningsuntech, By comparing apples with oranges. Of course it would require constructing one of each and then testing to see which one pulled in the most APs with the strongest signals. I also assume that for the full wave version one would need to re-calculate the critical distance from the back of the can to element mount location. I do like your method of hard mounting rather than using a coax connector. Mechanical connections are always less preferable for signal transmission especially at microwave frequencies. Sounder
navarrofeds5 years ago
thank you I have looked at diy cantenna for a while and this is the first that I have found that did no use a n-female chassis connector. this was very helpful and I will be building one soon thank you
deejaydee5 years ago
im going to buy a wireless adapter to connect to my friends wireless thats about a block away .. and i was thinkin of buying something cheap like the "ENCORE ENUWI-G2 IEEE 802.11b/g USB 2.0 802.11G Wireless Adapter" .. and im wondering will that work?
jefeickert6 years ago
(removed by author or community request)
2words: Grocery Store :D but any metal tin should work...i think..
(removed by author or community request)
z3r0 jefeickert6 years ago
Where I live Maxwell is still using metal tins.
Gksarmy z3r06 years ago
lol, i love the part where jef. was flaming me XD and it got removed thus rendering all my arguments invalid lol XD
ah, well, sorry :S cuz HERE they're made of metal :S umm hemmmmmm if u have an old tail/exhaust pipe/cylinder that should work basically the idea of this is to collect the wifi so any metal cylindrical item should work.
fenris6 years ago
also, could you not put a usb cable on it and then run antenna software that expects a usb antenna?
burningsuntech (author)  fenris6 years ago
fenris This is a passive device (supported by external electronics like a wireless card). Coax and USB cable are not the same and the antenna is designed for coax with a connection to a WiFi wireless card. I suppose that if you can find a usb wireless card to fit inside the can you could try it. After all. Discovery is what experimentation is all about. Good luck! raving apache
Indeed I do have such a thing, a Dell '1450 wireless USB adapter', that would fit into such a can very nicely. Is the can just a 'guide' or 'accumulator', then, or would I want to make some sort of connection to the can?
Gksarmy fenris6 years ago
this is like a giant antenna for routers such as Linskys. They are as a monitor to a computer, only receiving information, not decoding. Your dell 1450 wireless USB adapter is as burningsuntech implied, an active device. It actually decodes and picks up the wifi whereas this antenna solely picks up the signal. hope that helps!
fenris6 years ago
uh, i hope this is not too stupid, but why do you remove the metal end of the can and then go to a lot of trouble putting a metal end on the can? could you not just leave one of the original ends on there?
burningsuntech (author)  fenris6 years ago
fenris No. Not at all! The reasons were to allow easier soldering of the tubing to the can for the cable insert and to prevent the rippled bottom of the can from detuning the antenna. Removing the bottom accomplishes both objectives. Will it work without all the fuss. Sure. But i'm anal and am a perfectionist
Far out. This sounds to me like exactly what I need. There is an unsecured connection that I detect, but it is apparently just far enough away that I am either not able to connect at all, or have only very minimal connection quality. Every other possible connection detected in my neighborhood is secured. I suppose I could try knocking on all the doors in my neighborhood until I find somebody who is willing to give me the sign-in key, but that is not the revolutionary thing to do at all.
Great and inexpensive idea... However, I am looking for a wifi signal booster that requires on direction to my Powerbook. I have seen such a thing and cannot remember where/how it is done... Any help out there will be appreciated...
philipster6 years ago
if you wanted to optimize wireless even more could you wrap inculcated wire round the tin several times ?
burningsuntech (author)  philipster6 years ago
Philipster Since we are talking about microwave frequencies here, the gain may be increased by designing and adding a horn to the end, though I do not know how much gain will increase by doing that. Adding any metal around the tin would likely do no good as the wire and the tin would both be at ground potential. raving apache
Very Nice Instructable! Looks Great!
burningsuntech (author)  joejoerowley6 years ago
Thank you.
meddler6 years ago
Does this work with a macbook????
burningsuntech (author)  meddler6 years ago
meddler This antenna is strictly passive and can be used with any laptop, wireless router, access point or bridge as long as you have the proper connector to interface with it. raving apache