If you were successful, youвЂ™ll see that part of the cable jacket is present within the first crimp. The copper pieces will slice down, into the wires, and the crimp will push the plug together in two places. Put the plug into your crimping tool, and crimp it all into place. YouвЂ™ll see them reach the far end, following their assigned tracks. You might need to push with moderate force. Slide the wires as far into the ethernet plug as possible. Position the ethernet plug with the flat side up and with the opening for the wires facing you. Trim the wires back again, leaving about Вѕ inch exposed. Still, I follow the T568B standard, which calls for (left to right) white/orange, orange, white/green, blue, white/blue, green, white/brown, brown. The particular order you use doesnвЂ™t actually matter as long as you stick to it at each end. In any event, treat it well, because needless wrangling could damage the wire. Another approach is to hold both ends of the exposed wire and gently draw it across a curved table-edge. I like to hold the bundle in one hand and then tug my thumb and finger across the rest. Untwist and straighten the pairs of wires. This process ensures that youвЂ™ll have an exposed and unnicked section of cable to work with when making the first pass at stripping off the jacket, you may have scored or slightly cut the wires inside. Notch down at the end of the jacket, and tear another inch away, using your fingernails or the string inside the cable if available. Strip about 1 inch of the cable jacket away. Slide a boot onto the end of the cable, leaving the large boot opening toward the bare end of the cable.

If the cable that I plug between the two jacks is good, the cable will bridge each circuit, lighting one LED for each completed (and properly functioning) pair. I then wired a separate jack in a loopback configuration, so that pairs of wire complete the circuit on the opposite end, bridging 1 and 2, 3 and 4, 5 and 6, and 7 and 8. I wired an ethernet keystone jack to a 9-volt battery, a 470-ohm resistor (in series), and four red LEDs (in parallel) so that each pair of wires is associated with its own LED, looping through those parts.

Alternatively, you can make your own, as I did. To verify that the wiring is correct, youвЂ™ll also want a tester they retail for $25 or more. You may be able to borrow these tools from a friend or IT department at your work, or you can buy them online. YouвЂ™ll need a wire cutter, wire stripper, or pair of scissors, and an RJ45 crimper. I bought an assortment of colors so that I could keep track of my network wiring more easily. Buy plugs that match your cable choiceвЂ“solid-core or strandedвЂ“and enough boots to complement each plug. If it doesn't work, you've either built it wrong or the CSU/DSU isn't working properly.YouвЂ™ll be attaching ethernet plugs to each end of each cable, along with boots slightly behind them to protect the plastic tabs. If it does, you've successfully built the plug. Place the loopback plug into the T1 port and you should see the unit 'synch' to itself by indicating either 'Link' or having whatever is used for the WAN interface to show the unit now has sync. Test it on a 'known good' router with a CSU/DSU (T1 interface). Put the Cat 5 end into the crimper and verify all of the wires are pushed all the way into the pin slots and then crimp it down.Д©. You should now have 2 wires 'looped' in the cat 5 blank end with pin 1 connecting pin 4 and pin 2 connecting pin 5ДЁ. Put one end of the second wire into pin 2 and bend it in half and put the other end into pin 5.Д§. Put one end of the first wire (either one will do) into pin 1 and bend it in half and put the other end of it into pin 4.Д¦. If you are looking at it this way, the bottom slot is pin 1 and the top is pin 8.ДҐ. Identify the pin order on the Cat 5 end: hold it with the movable/press-side of the clip away from you and the metal contacts facing left. usually same colors (brown and brown/white, etc.)Д¤. Cut off about 2 to 4 inches of a Cat 5 cableДЈ.

How to make a ethernet loopback cable