An old cable or satellite box is no longer able to deliver a digital television signal due to it no longer being connected to the cable or satellite service provider's signal. The antenna input function of the cable/satellite box is not deactivated and can be used to convert the free TV signal received by the digital antenna into a format that a television set can understand. A video cable readily available in most homes or available for little cost at a computer or electronics store will be needed.
Place the cable or satellite box next to a TV. Plug the cable or satellite box into a power outlet. Screw the coaxial connector of the external antenna's cable into the "Ant" coax input on the back of the cable or satellite box.
Screw one end of a coaxial cable into the "Coax output" or "Out To TV" on the back of the cable or satellite box. Screw the other end of the coaxial cable into the coax input (sometimes labeled "Ant") on the back of the TV.
Turn the TV on with its remote. Press "Menu." Select the "System Setup" option, and then the "Video input" option. Choose the coax input. Press the "Menu" button.