Lincomatic's Homebrew Wi. Fi Antennas. Up. One of my latest obsessions is building DIY homebrew Wi. Fi antennas. Heinz Beans Cantenna. This is the first antenna I built. It's the ubiquitous circular waveguide. The resultant methane. Finding his online cantenna calculator rather intriguing, I set out to. Construction of the Biquad. I used Printed Circuit board scraps for the 110 x 110 mm reflector, but it will be just as effective if made out of sheet brass or copper. Thread Pt 1, Thread Pt 2, Thread Pt 3, Thread Pt 4. Welcome to the world of 3g wireless internet, antennas, coaxial cable, return loss plots and all sorts of nerdy stuff. This calculator is designed to give the vertical length (height) of a particular antenna, for the frequency and wavelength chosen. The result is my own cantenna. I wrote in in C++, based on formulae obtained from. ARRL Antenna Book. It's available on my free. Win. 32 console- mode EXE and full. In addition, Adam Lesser has kindly supplied a binary for. OS- X. Greg Rehm's calculator fixes the operating frequency at Channel 6 (2. MHz). which is the center channel in the USA, giving the best tradeoff if you want to. Channels 1- 1. 1. On the other. hand, my calculator lets you tune your antenna for maximum gain on a specific. ![]() Let's go through an example using my calculator. The syntax of. the program iscantenna diameter centerchannelwhere diameter is in mm. So to make an antenna optimized for Channel 6 using my. The Guide. Wavelength is the wavelength of our waveguide. The TE1. 1/TM0. 1 Cutoff frequencies. Now the interesting part is that if you wanted to. Channel 1, you would use a probe. This is a biQuad, and a double-biQuad antenna. You can find the construction guide (in Fr) here. As usuall the photos is in the Brest-Wireless gallery. Les Antennes pour les Radioamateurs - Suite, Yagi : liens : Free Antenna Designs. L-com Global Connectivity (http:// installs an outdoor WiFi booster. Today we are installing a. This DIY site shows how to make a homemade HD TV antenna. ANTENNA MAGUS: latest release update summary Channel 1. 1, you would use 5. What. this means is that there is a whopping 5. Channels 1 and 1. Experimenting with my calculator program, I've found some interesting. As the waveguide diameter increases, the difference in optimal. Channels 1- 1. 1 drops. From my studies, it seems that about 9. Channels 1- 1. 1; this is because it minimizes the. Channels 1- 1. 1 - > about 2. SWR curve across the Wi. Fi band is flatter. Contrary to popular belief on the Internet, a can length of 3/4 the waveguide. The ARRL Antenna book. I've found that adding more cans. A 4- can one is the longest I tried; I didn't write. Adding more cans helps launch the standing waves in the can better. I downloaded the EZNEC. I still don't have a good grasp of how to model a real ground plane. I started w/ a quarter wave whip. In the US, Channel 6 is the middle channel at. GHz. This makes a quarter wavelength about 3. I started with this. SWR and ended. up with 8. EZNEC shows SWR of 1. Wi. Fi band and gain of 4. B. max assuming a perfect ground (which we don't have). Below are plots of my EZNEC. Here is my prototype: It's just a piece of 2mm dia. Just for the hell of it I soldered on the ground plane, which is. The tape is just to keep me from shredding. How well does it work? I was amazed. Inside the house, I went the the place w/ the worst. SNR went up by over 1. B vs the built in antenna. Hope he doesn't mind my re- posting them. From the above photos, I estimated the dimensions below: wire: ~1. ODground plane to coils: 3. ID: 5mmcoil OD: 7mmcoil spacing: ~3- 3. Once again I used a 3. A nicer implementation would be to use a discarded hard. I am worried that the. When I get. a chance I will either encase the whole whip on a plastic tube or just support. Another idea is to. My initial tests were not that promising.. Therefore, this antenna is used in my current stumbling rig. Trevor Marshall's Bi. Quad. Trevor Marshall has posted plans, as well as NEC2 models for his biquad. The antenna can also be used standalone. I fashioned the reflector from a discarded tin can. The reflector is 1. The driven. element is composed of copper wire I got out of a piece of Romex, with 3. The antenna as pictured above was. Trevor explained to. I messed up the feed (the photos on Trevor's site are. Here is my revised feed: Instead of rigid coax as specified by Trevor, I just used some more copper wire. I'm not sure how this affects VSWR, but the antenna gave me. B more gain than my Comtelco patch clone during my initial tests. Bazooka Cantenna. I've been trying to hook up my brother, who is a professor at a local college to. He lives just on the edge of campus, and although the IT. Dept. Therefore, I decided to take matters into my own. There are tons of AP's just around the corner and out of LOS from my. Finally, one day I climbed up on his roof to see if I could get LOS and a signal. I used my. ORi. NOCO card in my Jornada, pointed my biquad through a tree, and amazingly got. B SNR! Now we were in business, but the 5d. B seemed a little too weak for. I decided a cantenna might be the way to go, so I built a new one using 3. The driven element is 3. The conical collector is 7. This was just a quick prototype so I made the. Here is what it looks like: Before trying it on the target site, I did some testing with my AP at home. Here. are the SNR's I got across the street from my AP: ORi. NOCO built in: 2. B2 cans w/o collector: 3. B3 cans w/o collector: 3. BTrevor Marshall biquad: 3. B3 cans w/ collector: 4. B (!)This is the highest gain antenna I've built yet. In my excitement, I dragged my. Jornada off a table while connected to this %$* thing and it fell on the floor. I fired up Pocket. IE on the Jornada, and was able to surf a little - . Since it was daylight this time, I was able to try out more places on. B SNR. Now. we're in business; I've got a little more margin to play with so when I hook up. LMR- 4. 00 cable to get the signal inside the house I won't get killed by. To be continued after I get the rest of the equipment to complete the. In the meantime, I played with the bazooka from the deck of my hillside house. AP I'd detected while stumbling. Mobile Mark clone on the dash). Plugging the. GPS coordinates in from the freeway into Microsoft Streets & Trips, it turns. AP is about 4 miles away! Using the bazooka on at my house, the SNR was. B (signal ~- 8. 8d. Bm). As a comparison, I also tried the biquad. Using the. biquad, the signal is unstable w/ max 4d. B SNR, and it catches the AP for only a. Collinear Omni. This antenna has a.
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