Use something that is rigid but bendable to make 4 rods. Find the Center of the rod and chop it in half. I recommend bending the rod 1st because bending and forming a longer rod is easier than a short one. Then use an octagon shaped piece of wood and drill holes in the side at the 12, , 3, , 6, , 9, and positions.
Drill holes in the side of the octagon about 2 inches deep. Add some Super Glue and a little electrical tape to shore it up. Be sure to check your curves again just in case you bent it up a little. Step 4: Feed horn and back Reflector Now we are going to work on the feed horn. This is the part the sticks straight out of the center of the dish that your USB device or router antenna will be fitted on.
Once the signal is reflected by the dish it will concentrate a point called the focal. This is the spot in the dish that will have the strongest concentration of signal. At this point you could just it mount up and be done with this step. Personally I like to get all I can so I am going to make a 2nd mini dish to reflect any signal loss due to miss adjustment or placement of the receiver.
Preheat the oven to and place a CD on top of a curved lid or glass condiment dish. Place them in the oven. It should only take a few minutes to soften the plastic. You are shooting for a circle about 10cm 4 inches round and cm deep. Take note CDs are made to take some heat and not bend. Bending it too far will cause breakage or deformation. I use a pot holder to apply pressure on the CD after removing it from the over and placing it on my glass condiment bowel.
CDs are cheap so wasting a few while you get it right is ok. If you want a more workable plastic get a small piece of Lexan from a hardware or home improvement store. Now Take the diameter and depth of the mini dish and plug it into Parabola. Take note of the focal length. Add the Focal Length of the main dish and the mini dish.
This is how long the center of the deepest part of the main dish and the deepest part of the mini dish has to be. Drill a hole in the mini dish and the wood center of your main dish. Install a rod passing it threw the mini dish and all the way thru the center ring of your main dish. Allow it to go all the way thru the main dish wood center so that it can be adjusted if needed. I used spray adhesive on stiff "cereal box" cardboard and stuck the foil the surface and smoothed it out.
Then I cut out the panel with the foil on it after the adhesive cured a few minutes. I then mounted the entire apparatus inside a plastic bucket. The bucket sits upside down outside in the rain. I lose about 1dB because of the plastic bucket so am running dB gain typically. Reply 11 years ago on Introduction. I will bet you anything if you hooked an antenna analizer to this the SWR would be horrible. And the gain is probly non existant?
When you work with SHF it tends to be really lossy So just hooking it up would lose half your signal. Two simpathy stars. By Corrugator Supercilii Follow. More by the author:. Here's one done by a plucky 5 year old Essential tools include a pair of safety scissors.
This one is made from a skinny plastic folder, cut from the template of a printout. Did you make this project? Share it with us! I Made It! Remote Control Light Switch by alanmerritt in Arduino. Reply Upvote. Sit infront of it and pray wifi signal will come from heaven? We have a few theories regarding the comparatively poor performance of our antenna: during transport I accidentally bent the copper wire a bit, and we did not manage to bend it back perfectly, potentially shifting wire from the focus.
Furthermore, our antenna dish is not a perfect parabola, but contains blemishes from the underlying sponge rubber, diffracting signals instead of focusing them. Unsurprisingly, the omnidirectional antenna is not sensitive to orientation, while the other two antennas are. Our parabolic antenna is also directional, albeit less consistently. In addition to the reasons listed above the length of our copper wire may also be responsible: since it extends beyond the focal point in both directions, signals which are reflected close to the focal point hit the copper wire as well, reducing directionality.
Our DIY antenna is a success: while it is not as good as an off-the-shelf omnidirectional antenna it is certainly good enough to receive Wi-Fi signals over a range of m, comparable to a non-DIY cantenna. It displays some form of directionality, if not a very good one. There are many possible improvements to this design. The easiest way to increase antenna gain and directionality is to increase its diameter. While mm is close to the maximum of the Prusa i3, it is possible to split the design into quarter dishes, assembling a dish twice as large.
Using a smoother material to cover the inside of the dish may also help. Finally, replacing the copper wire with a receiver only at the focal length of mm should increase directionality, at cost of a significantly more complex model. A variety of other DIY antenna models also exist, such as the cantenna model we compared against, Wok-Fi using woks or similar kitchenware as antenna dish , and many more.
And can be a fun side project! If you have any questions or comments feel free to reach out to me via my public inbox. This is a guide on installing and running NetBSD 9.
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