Connect your antenna to the HDMI input or the coaxial input, depending on what your TV has
Most Roku TVs have a coaxial input (the round threaded port labeled "Cable In" or "Antenna In") on the back. If your antenna has a coaxial connector, screw it directly into that port. If your antenna has a different connector type, you will need an adapter that matches both your antenna and your TV's input.
Some Roku TVs do not have a coaxial input. In that case, you can connect an antenna through an HDMI input using a digital tuner box — a separate device that converts the antenna signal into something your TV can display. This adds an extra step but works on any Roku TV with an HDMI port.
Once the antenna is physically connected, you will need to run a channel scan so your Roku TV finds the broadcast channels in your area. This is the step most people miss, and it is why they think the antenna is not working when it actually is.
Key Takeaways
- Roku TVs with a coaxial input accept an antenna cable directly; those without need a separate digital tuner box connected via HDMI.
- The physical connection is only half the job — you must run a channel scan in your TV's settings to find local broadcast channels.
- An antenna works on Roku TV regardless of whether you have internet or a Roku subscription, because broadcast channels do not require either.
- If your antenna cable does not fit your TV's port, you need an adapter that matches both the antenna connector and the TV input type.
Finding the right input on the back of your Roku TV
Look at the back of your Roku TV and locate the ports. The coaxial input is round, about the size of a pencil eraser, and has a threaded ring around it. It may be labeled "Cable In," "Antenna In," "RF In," or sometimes just "Coax." This is the standard port for antennas and cable boxes.
If you see this port, your antenna connection is straightforward. If you do not see a coaxial input, your Roku TV model does not have one built in. This is more common on newer, thinner models. Write down your TV model number (usually on a sticker on the back or in the Settings menu under System Information) and search the manufacturer's specifications online to confirm whether it has a coaxial input.
Connecting the antenna cable to the coaxial input
If your antenna has a coaxial connector (a threaded metal connector), hold the antenna cable in one hand and the TV port in the other. Align the connector with the port opening and turn the cable clockwise by hand until it stops. Do not force it — it should tighten smoothly with finger pressure alone. If it does not turn easily, you may have the angle wrong.
Make sure the cable is not kinked or bent sharply where it enters the TV. A sharp bend can damage the connector inside and cause signal loss. Route the cable along the back of your TV stand or wall in a way that keeps it relatively straight.
Using a digital tuner box if your TV has no coaxial input
If your Roku TV has no coaxial input, you will need a digital tuner box — a small device that sits between your antenna and your TV. The antenna connects to the tuner box, and the tuner box connects to your TV via HDMI. The tuner box decodes the broadcast signal and sends it to your TV in a format the TV can display.
Connect your antenna to the coaxial input on the tuner box, then plug an HDMI cable from the tuner box into any HDMI port on your Roku TV. Plug the tuner box into power. You can find digital tuner boxes at electronics retailers under names like "digital converter box," "ATSC tuner," or "over-the-air tuner." They typically cost between $30 and $100.
Once the tuner box is connected and powered on, you will run the channel scan on the tuner box itself, not on the Roku TV. The tuner box will display the channels it finds on your TV screen.
Running a channel scan to find broadcast channels
After the antenna is connected, go to the home screen of your Roku TV and select Settings. Navigate to TV Inputs or Antenna (the exact name varies by model). Look for an option that says Scan for Channels, Auto Tune, or Channel Search.
Select that option and let the scan run. This usually takes 5 to 15 minutes. The TV will search through all broadcast frequencies in your area and build a list of channels it finds. Do not unplug the TV or antenna during this process.
When the scan finishes, your TV will show you how many channels it found. If it found zero channels, the antenna is not receiving a signal — check that the cable is screwed in tightly, that the antenna is positioned correctly, or that you are in an area that receives broadcast signals. If it found channels but they are pixelated or cutting out, try moving the antenna to a different location in the room.
Positioning your antenna for the best signal
Broadcast signals travel in straight lines and are blocked by walls, metal, and dense objects. If you have an indoor antenna, try placing it near a window or on a high shelf. If you have an outdoor antenna, make sure it is mounted securely and pointed toward the broadcast towers in your area (you can search "broadcast towers near me" online to find their direction).
After you move the antenna, run the channel scan again. The TV will update its channel list based on the new position. If you still have weak signal on certain channels, you may need to adjust the antenna angle slightly or try a different room. Some areas have towers in multiple directions, so the best position may not be obvious until you test it.
Troubleshooting when channels do not appear
If the channel scan found zero channels, first check that the antenna cable is screwed into the TV port as tightly as you can make it by hand. Loosen it and reseat it to make sure the connection is solid. If the cable is loose, the TV will not receive any signal.
Next, verify that you are in an area that receives over-the-air broadcast signals. Not all locations have strong broadcast coverage — rural areas and some urban areas may have weak or no signal. You can check coverage in your zip code using online broadcast signal maps (search "TV signal map" and enter your address).
If the scan found some channels but not others, or if channels are pixelated, the antenna position is usually the issue. Move it slowly around the room and run the scan again after each move. Even a shift of a few inches can improve signal on certain channels. If you have an outdoor antenna, check that it is not damaged and that the cable is not pinched or bent.
Frequently Asked Questions
Do I need internet or a Roku subscription to watch antenna channels?
No. Broadcast channels from an antenna work on any Roku TV regardless of internet connection or subscription status. The antenna signal is completely separate from Roku's streaming services. Your TV will display antenna channels even if you have never set up a Roku account.
Can I use the same antenna for multiple TVs?
Yes, if the TVs are close together. One antenna can feed a splitter (a small device that divides the signal), and each output goes to a different TV. However, splitting the signal weakens it slightly, so this works best if you have strong broadcast coverage in your area. You can find antenna splitters at electronics retailers for $10 to $20.
What if my antenna connector does not match my TV port?
You need an adapter. Common antenna connectors include coaxial (threaded round), F-type (smaller threaded), and IEC (flat two-pin). Identify both your antenna connector and your TV port, then search for an adapter that converts between them. Electronics retailers sell these adapters for $5 to $15. Bring a photo of both connectors to the store if you are unsure which adapter to buy.
Will an antenna work if my Roku TV is in a different room from the router?
Yes. The antenna signal and the internet signal are completely separate. Your TV receives broadcast channels through the antenna cable and does not need internet for those channels. You can watch antenna channels even if your TV is not connected to Wi-Fi.
How often do I need to run a channel scan?
You only need to scan once when you first set up the antenna. After that, your TV remembers the channels it found. Run a new scan only if you move the antenna, move to a different location, or notice that channels have disappeared. Broadcast channels in your area do not change often, so rescanning is rarely necessary.