How to Set Up a Second Comcast Cable Box

By Greg Burosh

If you want to set up a second Comcast cable box in your home, there's no need to waste your afternoon waiting for the cable guy. Whether you're hooking the second box to the same TV, a different TV in another part of your house or through another device, the process involves only a few peripheral items. You will need an audio/video selector, a splitter and some cables.

Things You'll Need

  • Audio/video selector
  • RF cable splitter
  • Two sets of audio/video cables (check to see if you need composite, component or HDMI)
  • Two sets of coaxial cables
  • Third set of audio/video cables (for device hookup only)

Setting Up Second Box to the Same TV

Step 1

Plug the audio/video selector into an electrical outlet. Put one end of the audio/video cables into the appropriate outputs (composite or HDMI) of the system selector. Plug the other end of the cables into the television's audio/video inputs.

Step 2

Plug the first cable box into an electrical outlet. Put one end of the audio/video cables into the appropriate outputs of the Comcast box. Plug the other end of the cables into "Input 1" of the audio/video system selector.

Step 3

Plug the second Comcast box into an electrical outlet. Put one end of the audio/video cables into the appropriate outputs of the second cable box. Plug the other end of the cables into "Input 2" of the audio/video system selector.

Step 4

Place the coaxial cable containing the Comcast cable signal into the "In" input of the RF cable splitter.

Step 5

Plug one end of the coaxial cable into the "Out" input of the RF cable splitter, and put the other end into the coaxial input on the first Comcast box. Place one end of the second coaxial cable into the other "Out" input on the splitter, and plug the other end into the coaxial input on the second Comcast box.

Step 6

Switch between the Comcast cable boxes by pressing button 1 or 2 on the audio/video selector.

Setting Up Second Box to a Different TV

Step 1

Plug the coaxial cable carrying the Comcast signal into the RF splitter. Put one end of each of the other two coaxial cables into the "Out" inputs on the splitter.

Step 2

Plug the other end of one of the coaxial cables into the coaxial input on your original Comcast cable box. Your first box will now have a cable signal.

Step 3

Put the other end of the second coaxial cable into the coaxial input on the second Comcast cable box.

Step 4

Plug one end of the audio/video cables into the appropriate outputs on your second Comcast box, and plug the other end into the appropriate audio/video inputs on your television.

Step 5

Plug the second Comcast box into an electrical outlet and turn it on. Both cable boxes now carry a Comcast cable signal.

Setting Up Second Box Through a VCR, DVD Player or Other Device

Step 1

Follow the directions in Section 1 or 2, depending on whether you are setting up the second box through the same TV or a different one.

Step 2

Plug the audio/video cables running from your second Comcast cable box into the appropriate inputs of your device. Note: Do this instead of plugging the cables into the audio/video selector (Section 1, Step 3) or the television (Section 2, Step 4).

Step 3

Plug the third set of audio/video cables into the appropriate outputs on your device, and plug the other end into the appropriate inputs on your television. Your second Comcast cable box is now set up to run through your device.

Tips & Warnings

  • If you experience interference or reduction of signal quality, ground the coaxial cable containing the Comcast signal by running it through a surge protector.
  • If you are running a second coaxial cable containing a different Comcast signal, skip Steps 4 and 5 in Section 1 and plug one cable into each coaxial input on the Comcast boxes.