A coaxial cable connects a wall outlet to a device that needs a cable signal, most commonly a cable modem for internet service or a TV for antenna or cable channels. The threaded, round connector plugs into a matching port on the back of your device, and the other end screws into the coaxial wall jack in your room. If you’re staring at a coax cable or wall plate and wondering what to do with it, here’s where everything goes.
The Wall Outlet
One end of your coaxial cable connects to a round, threaded wall jack. This uses what’s called an F-type connector: a small metal cylinder with a pin in the center, surrounded by a threaded outer ring. You’ll find these outlets in living rooms, bedrooms, and home offices, typically mounted on the wall at about the same height as your electrical outlets. Some homes have them in every room; others have just one or two.
To connect, line up the cable’s threaded end with the wall jack and twist it clockwise until it’s snug. You want it finger-tight. A loose connection at the wall is one of the most common causes of slow internet speeds and poor TV picture quality, so take an extra second to make sure it’s secure.
Where It Goes on a Cable Modem
If you’re setting up internet service, the coaxial cable runs from your wall outlet to the back of your cable modem or gateway (the combination modem/router unit many providers supply). The port on the modem is labeled differently depending on the manufacturer. Look for “Coaxial,” “CATV,” “Cable,” or “Cable TV” printed next to a round, threaded input. It looks identical to the wall jack. Screw the cable in the same way.
From there, the modem converts the signal carried over the coaxial cable into an internet connection, which it passes along through Wi-Fi or an Ethernet cable to your devices. The coax cable is the link between your internet provider’s network and your home network.
Where It Goes on a TV
On a television, the coaxial input is usually labeled “ANT/CABLE In” or simply “RF In.” It’s the same threaded round connector found on the wall and the modem. You’ll find it on the back or side panel of the TV, often near the HDMI ports.
Plugging a coaxial cable into this port lets the TV’s built-in tuner pick up over-the-air channels from an antenna or a direct cable TV feed. Even in 2025, with streaming and HDMI dominating how most people watch content, nearly all modern smart TVs still include this coaxial input. If you’re using a digital antenna for free local channels, this is the port you need. If you have a cable box, the coax typically goes from the wall to the cable box instead, and then an HDMI cable runs from the box to the TV.
Following the Path Behind the Walls
Behind your wall plates, coaxial cables run through your home’s walls, floors, or ceilings and converge at a central point. In many homes, a single coaxial line enters the house from outside, where the cable company connected it. That incoming line then hits a splitter, a small metal device that divides the signal so it can reach multiple rooms.
Finding the splitter can be a scavenger hunt. Common hiding spots include the basement (mounted on a wall or between ceiling joists), the attic, a utility closet, the garage, or even a small metal cabinet near your electrical panel. If you open a wall plate and look at which direction the cable runs (up toward the attic or down toward the basement), that can point you in the right direction. In some homes, the splitter is mounted outside on an exterior wall near where the cable line enters the house.
Knowing where the splitter is matters if you want to rearrange which rooms get a signal. You can disconnect unused lines at the splitter or swap to a splitter with fewer outputs, which reduces signal loss.
Using Coaxial for a Wired Network
Your home’s coaxial wiring can double as a high-speed wired network using MoCA (Multimedia over Coax Alliance) adapters. These small devices plug into a coaxial wall outlet and convert the coax signal into an Ethernet connection. You place one adapter near your router, connecting it to both the coax outlet and the router. Then you place a second adapter in another room, connecting it to the coax outlet there and running a short Ethernet cable to your computer, gaming console, or streaming device.
The coaxial wiring already in your walls carries the data between the two adapters. MoCA 2.5 adapters can deliver speeds up to 2.5 Gbps, making this a practical alternative to running new Ethernet cables through walls or relying on Wi-Fi in rooms with weak signal. It’s particularly useful in older homes that are already wired with coax in multiple rooms.
Which Cable Type to Use
Not all coaxial cables perform equally. The current standard for home internet and HD video is RG6, which works for both indoor and outdoor runs and handles the high-frequency signals that broadband internet and HDTV require. If your home was wired decades ago, you might have older RG59 cable, which has a thinner core and is better suited for short, low-frequency connections. RG59 can bottleneck modern internet speeds and degrade HD picture quality over longer distances.
If you’re buying a new cable to connect your modem or TV, RG6 is the right choice for virtually any home application. For very long outdoor runs (75 feet or more), RG11 cable has a larger conductor that maintains signal strength over greater distances, but it’s thicker, less flexible, and overkill for the short run between a wall outlet and a device.
Getting a Tight Connection
A coaxial connection is only as good as its weakest point. A single loose connector anywhere in the chain, whether at the wall, the splitter, or the back of your modem, can cause intermittent internet drops, pixelated TV pictures, or slower download speeds. When connecting a coaxial cable, push it straight onto the threaded post and twist until firm. You shouldn’t need pliers, but you also shouldn’t be able to wiggle it side to side when you’re done.
If you’re troubleshooting a bad signal, check every coaxial connection in the chain: the wall plate, the splitter, and the device port. Corrosion on the connector’s center pin or a bent pin can also cause problems. Replacing a damaged cable is inexpensive and often solves issues that seem like they should require a technician.