how to build a cantenna at vegankid

We had great plans to build ourselves some cantennas at the AMC last weekend. But alas, there was so much to do and so little downtime, that we never had the chance. However, i did manage to stop by the table and pick up a nice little instruction manual. It reads as follows (i’m adding some pics to make things easier):

Spill the Beans: How To Build A Cantenna!
Have you ’bout had it with your neighbor’s WI_FI no giving you the signal you’d like? Wouldn’t be great if you two could just share and split the bill? Well, why don’t you just point empty cans at each other?! That’ll solve the problem! No seriously, that’s how cantennas work. You each point one at each other and the WI-FI travels through the ’spectrum’ into your computers!

A cantenna is basically an antenna made out of a can, hence the creative name: cantenna. The antenna is a directional waveguide antenna that increases the range of a wireless network. It basically just increases the reach of a Wi-Fi signal! They are fun to make and only cost a few bucks and an empty tin can!

Materials:
To build your Cantenna you’ll need:

N-Female Chassis Mount Connector
Four Small Nuts and Bolts (to fasten the connector to the can)
About a 2″ piece of copper wire
Empty Can (open on one end)
Pig Tail (male connector)
Nail Clippers
Solder and Iron
Drill (correct size bit for the width of your connector)
Ruler
Access Point (wherever you plug into the web)

An ‘N’ What?!
N-Female Chassis Mount Connectors The N-Female Connector can be found at any electronics supply store for a couple of bucks. it connects the cable from you wireless equipment to the antenna. Some of these connectors have screws built into them and in this case you won’t need the nuts and bolts.

Cans For the can, the best thing to use is one that has a diameter of 3″-5″ and is as long as possible. Cans of juice seem to be perfect size. However, a 6″ diameter coffee can will work fine. So eat up and clean out that can because it’s time to put it together!

STEP ONE: MOUNTING THE CONNECTOR
The location of the N-connector on the can is extremely important. To figure the location, a formula is used to see where the antenna needs to be placed to emit the proper frequency for that can’s diameter. To figure out how far up the can you’ll place the N-connector, you need to determine the wavelength that your can will generate. The diameter of the can determines the wavelength of the antenna. You can just use an online calculator at www.csgnetwork.com/antennawncalc.html where you can simply plug in the diameter of you can to get the wavelength values. Connectors on antennas are always placed at one-fourth of the measure of the wavelength from the bottom of the can.

(Example: Wavelength = 8″ so 1/4 Wavelength = 2″) Measure that distance with a ruler from the bottom inside of the can and mark it. Drill a hole in the spot marked. If you don’t have a drill a hammer and nail will work fine. That is where the N-connector will be located. Each can is different, so use the online calculator to find the wavelength for your can.

[NOTE: Make sure the hole is the right size for the N-connector you purchased.]

STEP TWO: ASSEMBLING THE CONNECTOR AND PUTTING IT IN THE CAN
Cantenna Assembly It’s time to take that copper wire and place it in the N-connector. The total length stiking out of the connector should be 1.21″ - including the brass tube that’s sticking out of the connector. Solder the wire into the connector while keeping is as up right as possible. Now the assembly can be screwed into the can. If you’re bolting it in be sure that the heads of the bolts are inside the can.

STEP THREE: CONNECTING TO THE ACCESS POINT
Pig Tails To connect your cantenna to your access point, you’ll need a special cable called a “Pig Tail.” You can make your own pigtail or buy one from most electronics parts suppliers. Make sure your pigtail has a male connector and that the other end has a connector that is appropriate to you wireless point. The length of your pigtail determines how far you cantenna will stretch from you access point to where your cantenna will be mounted. On a side note, cantennas are usually mounted outside your house and are pointed at the cantenna of whoever you are sharing internet access with. So it’s a cantenna to cantenna deal.