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What is PoE, power over the internet?

  1. Apr 26, 2012 #1
    Hello Forum,

    does anyone know what power over the internet technology is all about?

    I think it is about sending power through the same wires that carry data....

    Some wireless connection use that...why?

  2. jcsd
  3. Apr 26, 2012 #2
    There are some spare wires in the cat5 cable normally used for ethernet connections that can be used to send (a small amount of) power to remote devices.

    For instance, my net connection is though a coop which uses widely distributed 802.11 repeaters and access points. My actual receiver (known as a bridge) is about 150 feet up the hill behind my house, aimed at an AP about 2 miles away. The receiver is wired to a router in the house itself and is powered over the ethernet cable (POE) between the two. Without POE I would have to run separate power wires or rely on solar power to run the receiver.
  4. Apr 26, 2012 #3
    Thanks Schip666,

    thanks for the reply. This is my situation:

    I have a single computer. An ISP is broadcasting, from 4 miles away, a wi-fi signal, to my town.
    I am trying to understand what equipment I would need to catch that wi-fi signal and get the internet connectivity.

    To catch the signal I need a wi-fi antenna (dish, yagi, planar).
    A coaxial cable would connect to the antenna. The coax cannot be too long or too much loss will occur.
    A device that converts the wi-fi signal to ethernet signal would be needed so that I can run 40 meters of ethernet cable directly to my computer and surf the internet. The ethernet cable can be much longer than a RF cable and get little loss.....

    I found this link: http://www.ccrane.com/instruction-manuals/wifi-bridge-kit-connection-diagram.pdf [Broken]

    I guess the brigde is what you are referring to: it is the device that changes the wi-fi signal (2.4 Ghz) to an ethernet signal....correct?

    Last edited by a moderator: May 5, 2017
  5. Apr 26, 2012 #4
    That is very close to my situation. My receiver -- the "client bridge" in your diagram -- is 150 feet away, powered by POE over the ethernet cable. One little trick I stumbled on...my cat5 is running through garden hose to keep the bunnies from treating it like licorice vines.

    I now have a Nanobridge M2 from Streakwave:
    as the bridge. It has a small built-in parabolic antenna which is sufficient to get a good signal from a vertical whip antenna on the AP about 2 miles away. It is connected to a Linksys router in the house by cat5 cable, with the POE power supply in the middle. You may not need the router, but it adds some fire-walling along with IP addressing, distribution and wireless re-broadcast inside the house.

    I previously used a Tranzeo TR6000 (I think) bridge with a built in panel antenna, and a Senao CB3 with both a Yagi to the same AP and a larger parabola to an AP about 6 miles away (both using POE at the receiver), but the coop decided they liked the Nanobridges better so I swapped it out.

    I don't know if you can find any tech information on our site: lcwireless.org but it might lead you to more....
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