The cable box provided by Comcast allows customers to access all of its channels under various subscription plans. Comcast's digital channels, pay-per-view and On-Demand are only available through the cable box. Comcast also offers a DVR (digital video recorder) that records programs and has all the features of the cable box. For a service fee, Comcast will send a technician to install your cable box, but it only takes a few minutes to do it yourself.
RCA Cable Connection
Plug the coaxial cable from the wall outlet into the back of the Comcast cable box. The connector is metal with a tiny pin in the very center. Line up the pin with the hole in the back of the cable box and screw the connector in a clockwise direction until tightened.
Match the colors of your composite or component RCA cable plugs to the jack colors on the back of your cable box. Push the plug firmly into the matching color jack. Composite RCA colors are yellow (video), red and white (stereo audio). Component video colors are green, blue and red with separate red and white pair for stereo audio. The red and white audio plugs go into the "Audio Out" jack.
Insert the video RCA plugs into the back of your television. For composite cables, this is the yellow plug, and for component cables, it is the green, blue and red plugs. Match the colors of the plugs with the colors of the jacks and push to secure in place. Note the label for the input location on the back of your television
Match up and plug in the red and white stereo audio plugs, if you use your television for sound. To use a separate audio system, plug the stereo plugs into the appropriate jacks in your system.
Plug the cable box into a power outlet and allow the system to connect before turning on the cable box. Set your television for the correct input that you noted when plugging in the cables.
HDMI Cable Connection
Plug the coaxial cable from the wall outlet into the back of the Comcast cable box. Screw the coaxial cable's connector in a clockwise direction. The tiny pin will line up with the small hole in the middle of the cable box jack.
Line up the HDMI cable plug with the correct connection in the back of your cable box. The HDMI cable will only plug in when oriented properly. Push until fully seated in the jack.
Connect the opposite end of the HDMI cable to an HDMI port in your television. If you have more than one HDMI port, note the label of the one you used.
Plug the cable box into the power and wait for the system to connect. Turn on the cable box and set your television to the correct input that coordinates with the label of the HDMI port you noted previously.
For additional assistance with audio and video settings, refer to your television and audio system manuals. After making your connection, call 1-800-COMCAST or 1-800-266-2278 for activation of your cable box.