Ask Slashdot: DIY 4G Antenna Design For the Holidays? 135
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?"
Is a 7 Inch Swivel Blade Really Worth $30? (Score:5, Interesting)
Something like this costs 30$ http://www.wpsantennas.com/700MHZ-LTE-4G-Antennas.aspx [wpsantennas.com]
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 [wpsantennas.com] but without the $120 price tag since it's probably just a bunch of metal configured a certain way connected to a balun connected to the device. I know where the cell tower is from my parent's house, I just don't know how to construct something that will function better than the little device they have.
Also, I was kind of hoping that there were really cool designs people knew of that consisted more than just "a big stick of metal you point at the tower." However, like I admitted in the submission, I don't know jack shit about antennas.
Re:30$? (Score:4, Interesting)
I would say that an antenna like a cantenna [napoliwireless.net] would be the thing to look at.
Here's an instruction video [in.com] too.
The main thing with a cantenna is to have a 1/4 wavelength distance between the antenna in the can and the back wall and the antenna in the can shall be a 1/4 wavelength. pin.
Here's also a good site with another cantenna calculator [changpuak.ch].
And when you make your cantenna you should allow for fine tuning of the position and length of the antenna pin inside the can.
ANOTHER THOUGHT (Score:2, Interesting)
Another thought comes to mind. . . what is the cause of the interruptions the parental units are experiencing with the set-up they already have?
How far is it to the tower? what is the noise floor like between the tower and their house? [What happens at your neighbors house that may interrupt the signal gettting to your parents house?] Are they enjoying any other wireless-frequency obtained signals, like satellite? Do any of your neighbors enjoy broadcasting CB or single side band radio? Around their antenna in the home, are there any other electronics radiating interference, like wireless dvd or bluetooth, for instance? Do their interruptions happen at certain times of the day (you can ascertain what other activities happen at that time of day that may be causing interference)? Do mom & pop have metal implanted in their bodies which may be bouncing the signals coming in? If they are receiving their signal to the house, wirelessly, and then also they are wireless between their router and the device they use to get information, that presents multiple points of potential failure. Is the placement of the router in the house near a window that faces the direction of the tower? Are they then on the other side of the house away from where the router is placed? Would a signal booster work on the side of the house where the user is located? cjacobs001