How to Hook Up a Cable Modem to a Cable TV

When you sign up for high-speed cable Internet and TV service, you will usually be given a cable modem and a digital cable box. The cable modem will have an Ethernet port to use with computers and network devices, but it will also have an RF jack to use with your cable box. After running coaxial cable from the modem to the cable box, you can connect the television to the box.

Father and son watching TV at home together, back view
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Step

Connect your cable modem to its included power source, plug it in and wait for the power light to turn on.

Step

Connect one end of the coaxial cable to the RF port on the cable modem. Typically, this jack will be labeled as "Output" or "RF Out."

Step

Connect the other end of the coaxial cable to the RF/coaxial port on your cable box.

Step

Run either component or HDMI video cables from the output ports on the back of your cable box to the input ports on your television. Both component and HDMI connections can handle high-definition content, but HDMI will usually deliver a higher-quality picture.

Step

Turn your cable box on and use the "Input" button on your remote or TV to switch to the proper component or HDMI input.