Holy cow! A Satellite dish?!
Yup…You read that right!
Today, I’ll be doing a write up on creating your very own WiFi range extender using an old satellite dish!
The finished product
How does it work?
Now, we’re going to try and explain this without the fancy mathematical equations that goes into the positioning and curvature of the dish.
At its base, a satellite dish is simply a parabolic RF (radio frequency) reflector. WiFi is a type of radio wave, similar to those being transmitted by a satellite that’s orbiting the earth.
The dish is comprised of three main things:
- A parabolic surface
- A feed horn
- An arm to hold the feed horn away from the surface of the dish
In traditional satellite dishes, the feed horn is called a Low Noise Blockdown converter. Or LNB for short. It amplifies the radio signal that bounces off of the dish and filters out signals that don’t have a television channel on them.
The way the parabola is shaped makes the dish point upwards even if it seems as though the dish is pointing forwards.
Cool, but can I see some visual Aids?
Here we can tell that the parabolic dish doesn’t actually receive the best signal from having its center aimed directly at the source.
In order to understand this concept, think of a ball and a cone shaped bowl. If you throw the ball directly into the center of the bowl, all it’s going to do is bounce right back at you because of the flat surface in the bottom. However, if you throw the ball at the inside angle of the bowl just right, the ball is going to hit the side, then the middle, then it will come out of the bowl on a downward angle. Just like what we see with a satellite dish.
So…When are we going to build this?
1.) To begin with, you’re going to want to acquire an old satellite dish. Usually you can get these from your local junkyard or on-line, but I got mine from my grandmother who had just gotten a new dish installed.
2.) There will be a set of coax cables inside of the arm of the dish. This is what was used to connect the LNB to the house. You’ll need to remove these and you can either toss them out or reuse them for another project.
Coax cables inside the arm
3.) The next step will be to clean the dish in order to remove the dust and grime from weathering. You could use a Brillo pad to get everything off, but I didn’t bother since it won’t end up drastically changing the signal.
Cleaning the dish
4.) Afterwards, you’ll need to make a base for it. Feel free to get creative since it will most likely be a cylindrical mounting pole without any kind of bottom bracket on it. If I had the time or materials, I would have welded on a steel base. Make sure you have legs that extend out front. Otherwise your dish WILL fall forward.
5.) The next and final step is mounting your favorite WiFi card! I used an Alfa AWUS036NH external WiFi adapter with a parabolic antenna.
Since my card came with a sheath and a clip to go on the sheath, I simply clipped the card onto the arm and ran the cables through!
Clipped and ready to go!
Don’t worry! I didn’t forget.
I personally believe the results I received were exceptional, especially for a mis-configured dish. I went from 9 access points to a whopping 15! That’s 6 more access points than without the dish.
[details=With the dish]http://i.imgur.com/IbFVRwgg.jpg
Things to think on:
Something that popped in my head while I was writing this article was wardriving. Imagine mounting this atop a van or something!
What other things do you think you could use this for? Remember, all it really does is catch and reflect RF waves!
Do you have any DIY WiFi or RF equipment? If so, what?