love wireless, except that it needs a wire to power it! In many cases,
hanging your wireless access point or wireless gateway in the highest
location possible in your house will offer the best balance of indoor
and outdoor range. Placing your AP/Wireless gateway on the roof or
in your attic can be a major headache. We show you how to remove the
extension cord and power your access point or wireless gateway over
the Ethernet cable that you already have running into the WAN port
of the unit.
Making your own power over Ethernet
* WARNING - doing this wrong could
SERIOUSLY FRY your access point and may void your warranty, proceed
in mind this works with ANY access point or wireless gateway. Most
SOHO wireless routers or access points do not have Power over Ethernet
(POE) built into their products. Power over Ethernet allows you to
run only a single RJ-45 cable (Ethernet) to your access point, and
run the power over the unused pairs of wires within the RJ-45 cable.
In Category 5e cables, there are 2 pairs of wires (4 wires total)
that are unused and can be used to inject power into your cable. Running
power over your Ethernet cable can often save you time and extension
cords by trying to run power up to the access point. If you have your
AP or gateway in your attic or near your rafters in your roof, getting
power up to that location is tough.
The RJ-45 cable ends are shown before cutting and splicing (sheath
removed) (Click to Enlarge)
Power over Ethernet is a specification that allows for your router
or access point to draw its power internally from the unused pins
(4/5 and 7/8) in the cable. Since many routers do not have this, we
will "hack" a RJ-45 cable and "inject" our DC
power supply into the cable, and on the far end of the RJ-45 cable,
we will "extract" the power from the RJ-45 cable before
it goes into the AP or gateway. This is not true Power over Ethernet,
just a rigged version to help make your life easier!
The first step is to find your power supply for your AP or wireless
gateway. Examine the OUTPUT power, most of these are around 9-12v
DC. The ORiNOCO BG-2000 that we use for this tutorial is a 9V DC supply.
Find out which wire on the power supply is positive and negative.
The Agere BG-2000 has Tip positive, and the power supply positive
wire has a white stripe in it. (See picture 1
Cut your power supply down near the end that plugs into the gateway,
leaving about 6 inches. (See picture 1
) Strip the wiring around each end of the power supply and the cut
end. Make sure you keep note of which wire on each end is positive.
Put these aside.
Now, take your RJ-45 cable and splice into the cable about 6"
from each end and remove the sheath around a 2-3 inch area on each
end. (See screenshot from abive) Our cable is a 25 foot Category 5e
by Belkin. Pins 1/2 and 3/6 are the ones we DO NOT WANT TO CUT. Identify
the wires 4/5 and 7/8. In our cable, 4/5 is the blue and blue/white
wire, and the 7/8 is the brown and brown/white wire. (For help see
site) Cut these wires on the RJ-45 plug end, leaving wires 1/2
and 3/6 intact. Do this on each end of the RJ-45, being careful not
to damage or cut any of the other wires. Strip each of the cut wires
about 1" down. Twist the blue pair of stripped wires together,
and do the same with the brown pair. Do this on each side of the cable.
(See picture 1)
Now, take your POSITIVE stripped wire of your power supply end, and
twist that POSITIVE wire onto the blue pair. Take the NEGATIVE wire
from the power supply and twist that with the brown pair. (See photos)
Now take the small end of the power supply that you cut (See photo)
and find the POSITIVE wire. Twist the wire with the blue pair on the
other end of the RJ-45 cable. Take the NEGATIVE wire and twist that
with the brown pair. Proceed to the testing phase below, make sure
your cable works great and then tape it up with electrical tape, making
sure to protect the "hot" wires from the network wires.
(See pictures 1
The 4/5 & 7/8 pairs spliced on each end with the proper power
supply end (Click to Enlarge)
TESTING: Be cautious when you test. First, during construction
you would have tested the cable after you cut the wires 4/5 and 7/8.
This means the cable still works and you cut the right wires. After
you splice in the power supply ends, you should NOT plug it in to
the outlet, you should first test the cable without any power at all.
It should work fine.
Now, UNPLUG the RJ-45 from the PC that you are using to test, and
leave both RJ-45 ends unplugged. Now, plug in the power supply end,
and then test the gateway or access point for power. It should power
up fine, if not, kneel down and pray, wipe the sweat from your brow,
and check it again using the power supply in it's original condition.
This is a pain, but is safer than plugging in the gateway again with
your cable. Check your connections, use a multitester to be 100% safe,
and you should have no problems.
The BG-2000 with our custom POE (power over Ethernet) cable with gobs
of electrical tape. (Click to Enlarge)
in mind that if you make your own power over Ethernet cable that is
over a total length of 100 feet, you should do more research on the
resistance of the RJ-45 wires. You could inject 9V in one end, and
only come out with 6V or less on the other end depending on the total
distance. We found some great info on http://www.nycwireless.net