Adapting a Telephone Handset to a Cell Phone

Step 2 Opening Up the Coiled Cord

First, plug the coiled cord into the handset.

Now that the coiled cord is plugged into the old handset, cut the plastic connector off the exposed end of the coiled cord (the end that would have plugged into the old telephone body). Using a craft knife, remove about an inch of the outer insulation from the cut end of the cord. This should expose four wires.

Two of these wires (usually red and black) connect to the microphone (in the "mouth" and of the handset), and two other wires (usually green and white in the phone handset, but sometimes they are both white in the cord) connect to the speaker (in the "ear" end of the handset).