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How to make a crossover plug.

[rough draft, last updated April 23, 2004]

This guide explains how to make a ethernet crossover adapter, which will transform your straight-through ethernet cable into a crossover cable. I made this adapter after buying a sleek retractable ethernet cable that came with a couple of adapters. I didn't want to have to also carry around a crossover cable.
For anybody who doesn't have a clue what I'm talking about, a crossover cable is used to network two computers to each other, without a hub or switch. Straight-through cables are used for most networking purposes.

Start with an 8pin RJ45 coupler and a Rj45 connector. You'll also need a RJ45 crimping tool. I paid 2 bucks for the coupler, 25 cents for the connector, and I borrowed the crimper.
Open up the coupler.
Cut the wires very close to one side.
The wires inside the coupler aren't the same colors as the wires inside an ethernet cable. Here is the order of the wires:
1blue
2orange
3black
4red
5green
6yellow
7brown
8white

and the order they need to be inserted into the connector:
1black
2yellow
3blue
4brown
5white
6orange
7red
8green
Line up the wires as they would be inserted into the connector, and trim them so they are roughly the same length.
I tried at first to insert them one at a time, but I found it easier to hold them tightly as shown above and insert them all at once. Then, you can wiggle them individually until they are flush with the end of the connector.
I used a piece of 22gauge wire to help me force the coupler's wires all the way into the connector.
This adapter is ready to be crimped!

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