Comcast cable boxes for high-definition television subscribers work with a high-definition media interface, or HDMI, cable to deliver digital picture and sound to an HDTV set, including all Panasonic models. The HDMI cable carries HD video and multichannel audio signals through one cord connected from the Comcast box to your Panasonic HDTV. Comcast HD cable boxes feature on-screen menus and programming, so you can install one and be watching shows in a few minutes.
Switch off the power for the Comcast box and the Panasonic HDTV.
Attach the coaxial cable that delivers the Comcast signal from the wall plate to the "Cable IN" jack on the back of the cable box. Turn the coupler clockwise around the jack to hold the cable securely to the Comcast box.
Plug in the HDMI cable from the matching output on the back of the Comcast box to one of the HDMI inputs on the back of the Panasonic HDTV.
Turn on the power for the cable box and HDTV.
Press the video select button on the Panasonic remote control, release, and press again until the Comcast menu appears on the flat-panel HDTV.
Press the "Menu" button on the Comcast remote control supplied with your cable box.
Press the "OK/Select" button in the center of the Comcast remote to set up the cable box. Follow the on-screen prompts, using the up and down navigational buttons to select options for setting up your particular cable box.