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A DIYer's Quick Guide To Cheap Wireless Extension

An anonymous reader writes "This piece is described in one of the comments on it as 'a little piece of genius'... and I have to agree! Although Peter Cochrane seems a bit of a crack pot, the ways that he comes up with to get connected when he's out of range in the sticks are pure genius and he makes them appear really simple! Think old satellite dishes, USB dongles and plastic bags and you'd be on the right tracks to upping wi-fi signal by 4 bars." A perfect excuse to link to one of my favorite sites, if you want more details and photos on similar jury-rigged long-distance connections. However, your meterage may vary — I've found USB Wi-Fi devices to be pretty fickle under Linux, with some distros working way better than others.

22 of 148 comments (clear)

  1. Citywide Wireless by billy901 · · Score: 5, Informative

    Wouldn't it be nice if this technology was used to make a free citywide wireless internet? We just need a bunch of people with this ambition and it could be done. I once read a book, called When A Strange Comes To Town, in which some people had the same ambition. You can get the book from Project Gutenberg if you look around. It's a newer book that has never been copyrighted.

    --
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    1. Re:Citywide Wireless by Nos. · · Score: 3, Insightful

      Jury-rigged wifi extenders typically aren't the most reliable things in the world. They also tend to be unidirectional, though omni-direction is possible, you don't get as much gain. You also need to power them, as well as connect them back to the Internet at some point. In the end it all costs money, and someone needs to pay for it.

    2. Re:Citywide Wireless by Anonymous Coward · · Score: 5, Insightful

      It would be much more helpful to protect people from litigation when they open up their wireless networks to strangers. The only thing preventing me from providing free wifi is the tremendous risk of being sued and eventually having to pay for someone else's crimes.

      If you've been wardriving lately, you know that we don't need more access points, we need existing access points to be opened.

    3. Re:Citywide Wireless by a_real_bast... · · Score: 4, Informative

      on sailing ships a jury rig is a replacement mast and yards improvised in case of damage or loss of the original mast.

      From Wikipedia. Used in the 1800's, at least. Would you like to reconsider your previous statement?

      --
      You're making me think. You won't like me when I'm thinking.
  2. Rhombic Antennas by hardburn · · Score: 4, Interesting

    Does anyone know of any attempts to use Rhombic Antennas with WiFi? They're very simple and provide huge gain. Their typical downside is that the length of one leg needs to be 8-12 wavelengths, which means they're the size of a football field when you're dealing with most radio frequencies, but 2 GHz has a 0.15m wavelength. A point-to-point rhombic should easily fit on the roof of a house.

    --
    Not a typewriter
    1. Re:Rhombic Antennas by elgatozorbas · · Score: 3, Informative

      I suspect these antennas are typically aimed at much lower frequencies (say HF/VHF), and require a ground plane. The reason why I think so is that for (super) high frequencies, antennas are mostly self-contained (one piece you can attach to a pole) and don't require a large garden and poles and the like.This is not the kind of structure you use for pleasure, but because you have to (at low frequencies).

  3. !news by Thelasko · · Score: 4, Insightful

    everybody knows that old satellite dishes and Asian parabolic cookware can be used to boost wifi signals.

    --
    One of our competitors trademarked the term "hypothesis". From now on, we will call them "boneheaded ideas".
    1. Re:!news by jellomizer · · Score: 3, Informative

      Dont forget Pringles cans.

      --
      If something is so important that you feel the need to post it on the internet... It probably isn't that important.
    2. Re:!news by maxume · · Score: 3, Funny

      Dude, what carrier is offering a temporal calling plan?

      --
      Nerd rage is the funniest rage.
  4. Free... Really? by gamanimatron · · Score: 5, Insightful

    I get nervous when folks start talking about "free" services. Seems that more often than not, "free" actually means that I end up paying for power, bandwidth, and the army of bureaucrats that makes sure those bills get paid on time, and that their uncle's brother's company wins next year's bid.

    So, please, count me out. I'll rig my own parabolic signal booster if and when I feel like it.

    --
    cogito ergo dubito
    1. Re:Free... Really? by stranger_to_himself · · Score: 5, Funny

      ...I'll rig my own parabolic signal booster if and when I feel like it.

      That's my new sig sorted out then.

  5. Try this.. the strainer WiFi.. cheap too! by i_want_you_to_throw_ · · Score: 5, Informative

    I found this great instruction on Instructables (pops new) on how to create a usb wifi out of a 2.00 strainer from WalMart. Works like a champ!

    My friend lives across the Ohio River and we're able to send the signal across the river that way.

  6. Old news anyone? by b96miata · · Score: 4, Insightful

    I'm too lazy to search for how many times the satellite dish wifi setup has been posted on slashdot, but suffice to say I had one on my roof 5 years ago after getting the idea from a web page that was itself a couple of years old. (even the actual useful link added on by the editor is from 2004)

    It's not even a good writeup of the concept. Here's a summary of the "Genius":
    -Stick it on the end of the arm.
    -Electronics don't like water.
    -The sun is hot.

    There's nothing genius about this. It's a rehash of something people have done for years, sans details.

  7. Nobody wants it! by drewzhrodague · · Score: 4, Informative

    I am one of those long-time WiFi zealots, and it is clear to me that people just don't want free ubiquitous wireless internet -- or they just don't care.

    Here in Pittsburgh, there is occasional talk of some group trying to do this. There have been some people who have received funding, but they waste it, and their project evaporates. Between ten and twenty (or more) companies start off here, and either fade away, or move to some other city. telerama, hobnob are the two that stick out (for which I remember URLs to).

    Largest public network here is run by ONE GUY who just went and built it himself, Shadyside WiFi.

    Otherwise, there is chatter on some of the local lists, but by and large, nobody wants free city-wide wireless Internet. Just me.

    --
    Zhrodague.net - I do projects and stuff too.
  8. Can I draw your attention to... by Gordonjcp · · Score: 5, Interesting
  9. How to get long distance WiFi to work with ease by viking80 · · Score: 5, Informative

    10 years ago you might have had to improvise, but today you can get cheap high quality antennas and amplifiers that is a lot better than a USB dongle in an old satellite dish.

    My favorite source is http://www.hyperlinktech.com/
    and you can do your link analysis here:
    http://cgi.gbppr.org/wireless.main.cgi

    If you really need big distances, you can use an old 12' sattelite dish, but otherwise stick to the formula above. It will save you a lot of time and trouble.

    I have reliable links over 10km with 10mW running at 50Mb/s

    --
    don't cut it off www.mgmbill.org
  10. It's not that easy by Puls4r · · Score: 4, Informative

    It's not that easy - and you might be better off just buying a cheap unidirectional antennae I live in a rural community and a 3G USB dongle several months ago. The low signal strength meant I was on the slow end of the speed for 3G. I tried the exact thing he did, but tried some other options as well. First, I purchased a $50 unidirectional antennae. That improved my signal strength by 10db. That was enough to get me to the range of 1300 down and 400 up consistently, with full "bars". So then I unplugged the antennae, added a couple of active USB cables, and put the dongle on the roof (1 story up). That improved my signal 5 db without the antennae, and 3 db with the antennae. So now I had improved about 13db. Finally, I grabbed my old dish, and aimed it at the cell tower. Then I put the dongle in place of the amp unit. Please note that most dishes have offset amp units, so you dish looks like it's aimed "below" the tower. It helped several decibles. I replaced the unidirection antennae and put in the dishes sweet spot, and it got me nothing more. Short version - I was better off elevating the dongle and attaching a cheap unidirectional antenna than I was playing with the dish. I suspect that will be true of most who play around with this. Final note - I have experience making other antennas - AM, FM, etc. I can assure you it wasn't lack of knowledge that prevented any huge increase in signal when using the dish.

  11. Access more than one network? by Bombula · · Score: 3, Interesting

    Every year or so I hunt for a simple utility to allow me to connect to more than one wifi network simultaneously and boost bandwidth that way. Never had any luck. Anyone know if this is feasible or not? The apartment complex where I currently live has multiple secure wifi networks set up specifically for residents, plus a bunch of folks have unsecured ones based on local cable broadband they don't mind sharing. If there was a way to connect to all of them at once ... awesome.

    --
    A-Bomb
  12. You need load-balancing by GameboyRMH · · Score: 3, Informative

    I've been looking into a similar setup. You need multiple wireless adapters and a load-balancing utility.

    http://forums.remote-exploit.org/archive/index.php/t-7419.html

    A quick and dirty way to do it with Linux iptables:

    http://tetro.net/misc/multilink.html

    My goal is to create a monster wardriving setup for constant on-the-road connectivity.

    --
    "When information is power, privacy is freedom" - Jah-Wren Ryel
  13. Re:Nothing to See Here by brechin · · Score: 3, Informative

    It's jerry-rigged, not "jury-rigged," dammit!

    Actually, it is "jury-rigged".

  14. MOD THIS UP! by Iron+Condor · · Score: 5, Interesting

    I rarely do this, but this AC is making the only point that needs to be made here. My own home router could comfortably serve a block of my neighborhood including the nearby park (I tried) but I'm not going to open it up because under US law I will go to jail if someone uses my open WiFi to download childporn or some such.

    The cost to me would be minimal and I'd set the QOs such that the freeloaders wouldn't interfere with my own activities -- and if everybody did that, we'd already have free ubiquitous wifi in all cities in the US. Because there's always some server around somewhere -- it's been forever since I truly got a "NO networks found". They're just all locked down like crazy because of the absurd US laws that hold a communications provider (me!) responsible for what clients do with the services they provide for free out of the goodness of their hearts...

    --
    We're all born with nothing.
    If you die in debt, you're ahead.
  15. Not news... by jemenake · · Score: 3, Interesting

    Sorry, but this really isn't news. Hell... even *I* have done this, which means that it can't be anywhere near the cutting edge. :P The concept of putting a cantenna or bi-quad at the focal point of the dish has been out there on web pages for years. I fitted *my* dish so that I could interchange a cantenna or a USB dongle as the need arose.

    The advantage of the USB dongle is that you don't incur the line losses of the antenna cable if your laptop/PC is a long way from the dish. You can get around the problem of USB cable-length limitations by using some nifty USB "extension cords" which are basically a long USB cable with a 1-port hub at the end.

    I will add one thing that I haven't seen on any pages, however. Most satellite dishes have the arm positioned away from the centerline axis of the dish... usually below it, which must be accounted for when aiming. For example, if the arm holding your dongle/cantenna is 10 degrees below the centerline of the dish, then you'll be receiving signals from whatever is 10 degrees above the centerline. It's the same concept as flat mirrors... angle of reflection equals angle of incidence.

    Why does this matter? Well, if you are trying to communicate with a station that's at relatively the same elevation as you, then you're going to have to point the dish down toward the ground a bit. This can be very conspicuous... especially if, ahem, the other station's owner doesn't know you're communicating with them (cough, cough). The best solution that I've come across is to turn the dish upside-down so that the arm holding the dongle is on top, which allows you to point the centerline of the dish skyward again, so that it looks more like the other dishes in the neighborhood. Almost nobody will notice that the arm is affixed to the top of the dish rather than the bottom... and even fewer will grasp the ramifications of it.