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Ask Slashdot: DIY 4G Antenna Design For the Holidays?
eldavojohn writes "This holiday season I will return to the land of my childhood. It is flat and desolate with the nearest major city being a three hour car drive away. Although being able to hear the blood pulse through your ears and enjoying the full milky way is nice, I have finally convinced my parents to get "the internet." It's basically a Verizon Jetpack that receives 4G connected to a router. My mom says it works great but she has complained of it cutting in and out. I know where the tower is, this land is so flat and so devoid of light pollution that the tower and all windmills are supernovas on the horizon at night. Usually I use my rooted Galaxy Nexus to read Slashdot, reply to work e-mails, etc. I would like to build an antenna for her 4G device so they can finally enjoy information the way I have. I have access to tons of scrap copper, wood, steel, etc and could probably hit a scrap yard if something else were needed. As a kid, I would build various quad antennas in an attempt to get better radio and TV reception (is the new digital television antenna design any different?) but I have no experience with building 4G antennas. I assume the sizes and lengths would be much different? After shopping around any 4G antenna costs way too much money. So, Slashdot, do you have any resources, suggestions, books, ideas or otherwise about building something to connect to a Jetpack antenna port? I've got a Masters of Science but it's in Computer Science so if you do explain complicated circuits it helps to explain it like I'm five. I've used baluns before in antenna design but after pulling up unidirectional and reflector antenna designs, I realize I might be in a little over my head. Is there an industry standard book on building antennas for any spectrum?"
Start with ARRL (http://www.arrl.org/)
Antenna Handbook: http://www.amazon.com/dp/087259694X/
*The* Handbook: www.amazon.com/dp/087259419X/
Exactly, Pringles cost way less than $30
At the higher frequencies like 1.3GHz (LTE), the wavelengths are so small that the corresponding antenna features are also very small. They have to be extremely precise if you want the gain to actually be at the right frequency, and even then it usually takes some trial and error. Do you have a chemical or laser PCB etching machine, and a cellular antenna analyzer (Saw one SUPER cheap on ebay for $300 once). Otherwise, just making random things could result in reflections damaging your transmitter. This isn't like putting together a 1/4-wave dipole on 2 meters.
But you could try fashioning a parabolic reflector dish and put your existing antenna in the center of it. I've heard of people doing that with cell phones and wi-fi adapters before.
How about posting some pictures of the milky way? I've only barely seen it once while on Hilton Head island.
http://www.dslreports.com/forum/r27484816-DIY-3G-4G-LTE-Yagi
http://bcbj.org/antennae/lte_yagi_diy.htm
Something like this costs 30$ http://www.wpsantennas.com/700MHZ-LTE-4G-Antennas.aspx
Ebay has things for 20-25$ Did you look at these options before deciding to building your own?
If you're telling me that works and that's the best I can do, then okay, you've got it figured out and I just don't understand antennas at all.
Like I said, I googled and looked for costs. The models that I see on your link that are $30 are 7.72” in length and look like the same things that come with any wireless router. I assume the Verizon Jetpack already has an antenna of this quality. What I was hoping for by asking Slashdot was that someone would belittle me and tell me how to build something more like this but without the $120 price tag since it's probably just a bunch of metal configured a certain way connected to a balun connected to the device. I know where the cell tower is from my parent's house, I just don't know how to construct something that will function better than the little device they have.
Also, I was kind of hoping that there were really cool designs people knew of that consisted more than just "a big stick of metal you point at the tower." However, like I admitted in the submission, I don't know jack shit about antennas.
My work here is dung.
http://bcbj.org/antennae/lte_yagi_diy.htm
Decent instructions for an LTE yagi.
scrap the tons of copper and steel you have, then buy an antenna.
I disagree. For $120 you are basically getting exactly what the OP described in one of his responses: a bunch of metal configured in a certain way.
Antennas are one of the easiest "geek projects" to do, and if the OP has access to the materials described, it should be a fairly simple (2-4 hours) project...
Actually, just googled "DIY LTE Antenna" and came across this . Apparently 4 hours to build, and cost all of $10.
Sure from a pure time/money perspective, you are only saving $27/hr, but IMHO it's time well spent.