This is a paraboloidal reflector dish, more or less a sattelite dish, that can easily be made from two sheets of plywood or other board, chicken wire or other mesh, and cable/zip ties.
It works by reflecting the microwaves of wifi or mobile signal and focusing them onto a receiver such as your phone, USB wifi adaptor, etc.
As long as the gaps in the metal wire mesh are smaller than about 12mm across they should reflect the signal as if they were a solid surface, except much lighter, cheaper, and easier to work into a smooth curve.
|2 Sheets Plywood / OSB / Other Board
Standard size; 1200x2400 / 1220x2440 / 8' x 4'
12mm thick gives a nice solid result, but 6mm also works, is cheaper, lighter, and quicker to cut.
200 Cable Ties / Zip Ties
2 Meters Fine Chain
String / Twine
|Print Templates:||3D Model (zipped)|
This tutorial is up to date, but isn't yet fully detailed. It does contain all the information you need to make the dish, but I will be writing something more complete and easier to follow soon. However it is a very easy build process and you should be able to make it from what's here. Email me if you have any questions.
First, mark out the templates on plywood. You'll need 4 of the red one, 4 of the blue one, and 2 of the green:
This is if you want to make the 1.5 square meter dish, you'll need to scale the numbers for different sizes.
To draw the parabolas the easiest way is to get yourself some light chain. When a chain hangs it makes a catenery curve, which is reasonably close to a parabola.
Mark off a length of chain as described on the template (135 cm for the blue, 160 for green).
Attach that length to the ply at the points marked, making sure they are the right distance apart.
Spraypaint over the chain to mark it's curve.
The 70cm radius circular curve on the red piece is easiest done by attaching your pen to a 70cm length of string to draw the radius.
Cut out the templates with a jigsaw or similar. Once you've measured and cut one of each type of piece (blue, green, red) you can use it as a template to draw the others.
Drill five holes close to the edge of each section of curve for putting cable ties through when you're attaching the mesh. Slot them all together, like so:
Place a 2 meter length of chicken wire in the top half of the dish and start attaching to the wood with cable ties put through the drill holes and around the wire. Start from the center of the dish and work your way out, section by section, keeping the mesh as tight as possible.
Tie two lengths of string across the dish so they meet at the centre of the front opening. Get this as tight as possible. This is the focus of the dish and where you want to attach your wifi or mobile reciever device.