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Using an Old Satellite Dish as a WLAN Antenna

Posted by ryuzaki0 on from the rolling-your-own dept.

=m8s=Dark Underlord writes "I was browsing for wireless stuff and came across this link that shows how to use an old satellite dish as an 802.11 antenna." The directions tout the range as being 10 miles given line of sight. We've had other stories about building antennas, but I think these are cooler because of their focused nature, but a Primestar dish is a little tougher to locate than a Pringles can or a floppy disk.

5 of 225 comments (clear)

  1. Big Dish... by nitrocloud · · Score: 5, Interesting

    My grandparents have a satelite dish that's about 10 feet in diameter... so should that give access to about 30 miles away? (I know it wouldn't, but it'd be neat to crank the amps)

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  2. 12 Miles at 5Ghz with Primestar Dish by ArkiMage · · Score: 5, Interesting

    Where I work our internet connection is via a WISP that uses this "technology". We have a Primestar dish on an elevated pole aimed at a mountaintop 12 miles away. 5Ghz and also a backup 802.11b radio with Yagi antenna that needs an amplifier to go that distance, but does so fairly well. The less-informed employees think the "dish" points to a satellite, not noticing the odd angle it's mounted at :)

    http://www.planetc.com/ is the ISP

    1. Re:12 Miles at 5Ghz with Primestar Dish by MemoryAid · · Score: 5, Interesting
      As I recall, most of the satellite dishes these days have an offset feed, so it is not obvious which way they are pointing. In fact, they usually point a little higher than it appears. That is, a vector normal to the center of the dish points lower than the main lobe of the antenna pattern.

      During a trip to Fairbanks, Alaska last year, it struck me as odd (well, odd looking) that the satellite dishes were pointing at the horizon. The offset-feed dishes looked like they were pointing at the dirt.

      If you want it to appear that your dish is pointing to a satellite, you could mount it with the feed horn on top, giving the appearance of a skyward view.

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    2. Re:12 Miles at 5Ghz with Primestar Dish by bill_mcgonigle · · Score: 4, Interesting

      We have a Primestar dish on an elevated pole aimed at a mountaintop 12 miles away.

      How the heck do you sight something like this in? You have to be accurate within a few seconds, don't you? A search pattern would take forever with that narrow of a beam, wouldn't it?

      Some of the high-end telco gear has a built-in telescope, but those are precision aligned at the factory.

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  3. Re:No kidding. Get the real thing. by cjsnell · · Score: 4, Interesting

    I did a similar setup recently for my father's bicycle stores and here is a photo gallery of the results. I have an aversion to Linksys (their tech support is horrible) and so I became a D-Link convert a few months back. We bought eight DWL-2000AP access points/bridges (you can select the mode via the web interface) and eight of their DWL-P100 Power-over-Ethernet kits. We linked our warehouses to our stores via 24dBi grids (from hyperlinktech.com) and, like you, placed our APs on the mast underneath the antennae. For our enclosures, I chose some inexpensive but very well-made Davis Instruments enclosures. They are NEMA-4 rated and are sealed against the elements. We're a dealer for Davis so we got them really cheap. Being in South Texas, I was concerned about heat in the boxes so I built custom heat shields, which fit around the NEMA enclosures. I built these from R-Matte (which looks like foam plywood) and foil tape. I also used the foil tape to turn cheap-o indoor grade CAT5e into psuedo-outdoor grade cable.

    Chris