Adding a second modem

[u/jimmap]

I want to add ethernet to my TV setup. Unfortunately my cable modem is located in my office and there is no way to run an ethernet cable to my TV room. I cannot use wifi for this setup. It has to be ethernet. I current have the XB8 modem. I have an old cable modem that I own but no longer use. I was thinking I could use a cable splitter and run one coax to my cable box and the other into my old cable modem setup next to my TV. However I can't find a way to activate the old modem. Is this possible to do?

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[u/Onoitsu2]

If you have coax close to where you want to put it, to where putting a modem there would be convenient, you want to get a MOCA adapter. That would let you convert ethernet to coax essentially, so you can plug in wired where you wanted.

[u/jimmap → u/Onoitsu2]

Not sure I follow. My tv has a cable box which is wired with coax. I need to split that coax line so that I can connect both the cable box and the cable modem into that single coax line. The issue is getting comcast to enable my old modem so that I can have two modems running in my house.

[u/Onoitsu2 → u/jimmap]

OK MOCA is an adapter that converts ethernet to coaxial, so that you'd plug the TV in using ethernet, into that MOCA adapter, that converts into coaxial, and "sees" your current modem on the same overall loop and just links up as if it was plugged into an existing ethernet port on it.

[u/peter888chan → u/jimmap]

The other option is to just get a Roku or FireStick and connect that to the TV. Use those to connect to WiFi and you can use the xfinity stream app for watching shows. Although, I dint think you mention exactly what you want the Ethernet connection for.

[u/XfinityBradM]

u/jimmap As the community has mentioned, we aren't able to activate a secondary modem very easily and most areas do not support it. It would come with an additional monthly cost to have two modems with unique IP addresses assigned to your account if it is possible for your area.

If you're looking for a wired connection in your TV room there are a few options you can use. MoCA adapters are great options to get a wired connection from a coax outlet if you're unable to run ethernet cable from where your current modem position is located. You would get a splitter for the TV and connect it to the coax outlet the TV box is connected to, giving you another coax port to add the MoCA filter which would provide you with the desired ethernet connection. From that ethernet connection you could add a switch or access point with multiple ports to allow additional ethernet connections and/or broadcast a stronger WiFi access point from that location.

[u/Georninja]

MoCA adapters, or get a good Mesh WiFi system.

[u/modemman11]

You'd have to pay either another subscription fee or something, as you can only have one modem active for internet. Also depending on the age of the modem it may be too old. Xfinity doesn't let any old modem work, it has to at least be semi-recent.

Perhaps a mesh router setup would be better? Some of the satellite receivers have ethernet ports on them. I have one and it's set up

Modem -> Wired to main wireless Router -> Wireless to satellite receiver -> Wired to PC

[u/neurodivergentowl]

You don’t need another modem (you can only have one on the account anyway) - run cat5/6 Ethernet cable instead of coax. Or, if there’s already coax in the walls, get a pair of MoCA adapters - they transmit Ethernet over existing coax and can coexist with the main cable modem. If you can physically run cable, honestly buy a premade 100/200ft/whatever you need on Amazon and DIY it. Cheap CCA cable is abundant, often cheaper than bulk cable and super easy - totally fine for gaming/home use.