How to Make a Rotary Phone Work With Your Phone Jack

Old rotary-style phones were equipped with a cable that wired directly into a small phone box on the wall. When you purchased your phones from the phone company, they would come out and install them. Later, you were able to purchase a large, four-prong plug that connected into a four-prong outlet. This allowed the phone to be unplugged and moved to a different location in the house. Through miniaturization, the modern modular jack was invented. To make a rotary phone plug into a modular jack, you need to change the cable.

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Standard black rotary telephones were all configured the same inside.

Installing a Modular Plug on a Rotary Phone

Step

Remove the cover of the rotary phone. Turn the phone upside-down and loosen the two screws holding the cover on. One will be in the middle front and the other in the middle back. The screws should remain in the phone — only loosened from the cover.

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Step

Locate the wire coming into the phone. There should be four wires — red, yellow, black and green — attached to four screws using U-shaped blade connectors. Loosen the four screws and remove the four wires, noting the location of the colors.

Step

Prepare your modular wire. The best type of modular wire is one with a modular jack on one end and four U-shaped blade connectors on the other. But these may be hard to locate. Next best is a thick modular wire that can be stripped.

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You may have to cut off one modular jack at the end and strip the wires.

Step

Connect the new modular phone wire to the screws. The only wires that are used for normal calls are the red and green wires. Connect the red and green wires to the appropriate screws inside the phone.

Step

Replace the cover on the phone and tighten the screws.