Telephone jacks can be either flush or surface mounted, so be sure to buy a replacement jack that fits your particular setup. Also, never work on a phone line during a thunderstorm, since lightning can travel down the wire causing serious injury. To disconnect the line, find the telephone interface box which is usually mounted on an outside wall where the phone lines runs into your house. On older interface boxes without a test jack, unscrew the terminals and detach the wires, remembering which one went on which terminal. Remove the jack from the wall, noting which colored wires are hooked up to the terminals so you can match them to the new one.
On the back of phone jacks, there are usually four connections—one red, one green, one black, and one yellow. The red and green "Christmas trees" wires power the first, or primary, line in your home. The black and yellow "bumble bees" wires don't get used unless a second line is added to your home. Adding a second line to your home is an easy task that even the least experienced do-it-yourselfer can do without costly interference from a telephone technician. First, let's look a few scenarios where someone may need a second line in their home:. We'll also go over adding a line to a room that currently doesn't have a phone jack, so you will be able to pick and choose where you want the second line to be located. The first step to adding a second line is calling your phone company.
It only takes two wires to connect a phone , but most house wiring contains four wires. The red and green wires are on the two center terminals of a normal phone jack, and the black and yellow wires are on the two outer terminals. This arrangement allows most normal houses to handle two phone lines very easily. Many if not most line cords that you receive when you purchase a phone to go between the wall jack and the phone only have the two center wires.
Note that the connector on the other end of an RJ connector is wired in reverse order. That is, if you stretch the cable out flat, the black wire stays on the left all the way to the other end, including through the connector with the hook oriented down also. Also note that the RJ connector has six terminals on it. Only the middle 4 are normally used. Line 1 is the center pair: red and green, as in Christmas.