Thomas W.P. Slatin

I’m no electronics genius, but I know a thing or two about building homemade gadgets.  The gadget I built today is intended to boost Wi-Fi signal.  For my purposes, this will be used when I’m out on the road trying to get my email, surf the net, and write my blog (all at the same time).  But whatever your situation, or intended use, this homemade device is designed to convert a standard omnidirectional antenna into a makeshift parabolic antenna.

While I could write an entire dissertation as to how the electromagnetic spectrum works and can be manipulated to achieve greater distance or signal gain, I’m going to just give you a few simple concepts to keep in mind while you build this reflector.

An omnidirectional antenna is one that resembles a flag pole.  This type of antenna broadcasts a signal in all directions.  It’s also the most common antenna found on Wi-Fi products, or so I have been told.  If you’re clever, you could remove the antenna from your Wi-Fi router, card, or whatever, and replace it with a different antenna.  However, I’m going to advise you not to, based simply upon common sense.  It is never a good idea to go screwing around with electronic devices unless you really know what you’re doing.

Click the images for the original-resolution image.

You will need a handful of things found around the house.  All of these items I was able to grab out of my garage.  I would have built this thing in my garage, but the kitchen table was near a nice air conditioner.  These items include a soda can (drink or empty it before you begin), a pair of scissors, a utility knife, some electrical tape, a Wi-Fi product (with a similar antenna), and a piece of plastic.  You might also consider safety goggles and gloves (safety first)!  If you don’t have a piece of plastic, poster board or cardboard will work, but won’t be as durable or easy to work with.

By the way, the antenna and adapter (on the left of everything) is called a Wave RV II and was purchased from Radiolabs.com.  They have a huge selection of Wi-Fi and radio products.  So be sure to scope them out!

The first step (after getting all your materials together) is to cut off the end of your soda can.  Be sure that the can isn’t full, or you will have a nice sticky mess to clean up.

This is what a soda can looks like when it’s missing its bottom.  Be careful of the sharp edges of the can!!!  Anyone who has ever worked with sheet metal will tell you that newly cut sheet metal can be extremely dangerous.  Take proper precautions.  Gloves and safety goggles come in very handy at this point.

This is what the inside of a soda can looks like.  It’s aluminum, and resembles the outside of a soda can, just a whole lot shinier and less advertising.

This is the stage when things start to get really tricky.  You will need to cut the can so that it has four corners, which meet as close to 90° as possible.  It doesn’t have to be exact, but the closer the better.

With all the sides cut, it’s time to tape the can to the plastic.  I would have used glue, but I prefer tape.  It really doesn’t matter, as long as the sharp edges are covered and the metal and plastic bond together.

Now things get a little simpler.  Using scissors, cut the plastic along the taped edge, being careful not to separate the metal from the plastic.

The bigger the better rule applies here.  Just like a bigger antenna will increase gain and reception, the bigger the reflector you use, the more signal will be boosted.  The goal here is to contain and reflect the signal.  I used cable ties to secure and bend the reflector into shape.  Ideally, you want a half-pipe.  If you are clueless, ask a snowboarder or plumber for assistance.

Here is the finished product.  To boost Wi-Fi signal, you must identify the direction the signal is coming from.  Pointing the shiny side towards the signal source boosts the signal tremendously, while pointing the shiny side away from the signal source drastically decreases or blocks the signal.  Experiment with signal strength measurement software, or use NetStumbler.  If you’re setting up a long-range Wi-Fi link, have one person at the computer monitoring the signal strength while another person slowly rotates the reflector until the best signal is achieved.  If you are using this setup for wardriving, be sure to stop and park somewhere before toying with it.

Have fun!

Posted under D.I.Y., Everything Else