Making a cantenna

So for some strange reason, I got the wardriving bug again.
Cousin James got me thinking about building a 802.11 antenna.
He wants one to try and leech broadband off one of his neighbors.

I decided to build a cantenna based on the design I saw on this wonderful page.
The design I used is known as the "Big Chunk" cantenna.
The detailed how-to is located here.

The only bit you can't buy in a local store is a card to connector pigtail.
The pigtail connects the tiny connector on the PC card to a more standard RF connector.
Typically the pigtail is to a type N connector.  I bought mine from Hyperlink Technologies.

We picked up Type N cable connectors and bulkhead connectors at the local
electronics store.  Not a Radio Shack, a real electronics store.

Next I had to pick up a couple 40 oz. cans.
The supermarket had no 'Big Chunk' stew, so I made
the choice of chili and mini-raviolis.  I think all 40 oz. cans are the same size.

I opened the can, saved the chili in tupperware, and then washed the can.
The chili grease took a good amount of soap and hot water to get out.

Next I got a piece of heavy copper wire for the driver element.
I used standard Romex that I stripped the jacket off of and grabbed the ground wire.

Since I work with an engineering shop, I borrowed a real soldering iron.
I set up my station in the kitchen.  My wife loves when I do projects in the kitchen.
Yes, I'm using the Fry's ad page as my work area.

Heating and preparing the surfaces.

The actual soldering of the element.
Be careful, the copper will get hot very fast.
Newbies to using a soldering iron should think about heat transfer
before they begin to solder, lest they burn their fingers.

Next I prepared the can.
Note my proper protective clothing.
At least my wife was happy I was doing this outside on the back porch.

Again, note the proper method of securing the can during drilling.
Safety first!

After a bit of tin knocking and drilling, I was able to fit the bulkhead connector into the hole.

Viola!  A driver element.
The length is incorrect, I have not cut it to the proper size.
Measure twice, cut once, my father says.
I haven't measured even once here.

The completed pigtail -> cable -> cantenna assembly.

I head out to my front porch and pick up a neighbor on the next street.
How do you do MercilessMing?

While not a great signal level, it's much more than I ever picked up before.
I could never even see the other access point from the house.
The gain I was seeing from the cantenna was around 15 dB.
To those that don't understand decibels and logarithmic scale, you can translate
15 dB to 'a whole hell of a lot' of improvement.

Before tuning the driver element, it was lunch time.
Obviously, I ate the chili.
You didn't think I'd throw away the chili did you?

James came over around this time and started making his cantenna.
Soon I was cooking his mini-raviolis.
Mmmm, mini-raviolis....

Here is the completed antenna.
I think it needs a few stickers...

An inside shot where you can see the trimmed driver element.

The next day I pointed the antenna out the window while my wife drove us
to our friend's house.  The laptop was running Netstumbler and beeping frantically.

Let me tell you any woman that lets you point a tin can out the
window with a laptop beeping constantly as it acquires new 802.11
access points while she's driving is a keeper. 

On the two mile drive I picked up over 30 802.11 networks,
only about a third of them were even secured with WEP.

The fun is just beginning.


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