A bunch of old antenna TVs on test channels.

So, you’re trying to watch free over-the-air TV, but you can’t find any channels. That’s perfectly normal. You just need to run a quick channel scan (or rescan), and you’ll be good to go.

Why Do I Have to Scan for Channels?

Digital television (ATSC 1.0) has served as the standard for free, broadcast TV since the ’90s. And like any 20-year-old technology, it’s a little quirky. You’d expect a TV to know which local stations are available, like a radio, but that isn’t the case. Instead, your TV keeps a list of which stations are available. Weird, huh?

Do you know how old TVs (and radios) had to be tuned to stations by hand? Well, when you scan for channels on a TV, it’s basically performing that process for you. The TV slowly runs through every possible television frequency, making a list of each available channel along the way. Then, when you go to watch TV later, you’re just flipping through that list. Naturally, that list needs to be updated every once and a while, and you have to start the scanning process all over again.

When Should I Scan for Channels?

You need to scan for channels every time there’s a change in local broadcast frequencies. That means you have to rescan every time you move, every time you buy a new TV or antenna, and every time a local TV station changes to a different broadcast frequency.

In this past, this roughly translated to “if the TV ain’t working, scan for channels.” But right now, America is undergoing a broadcast TV transition. Due to an FCC mandate, broadcasters are steadily switching over to 4K-ready, ATSC 3.0 compatible frequencies that don’t interfere with cellular frequencies. As a result, all TVs are going to lose track of local channels slowly. Plus, entirely new channels could pop up in your area, and your TV won’t know that they’re there.

The solution? Scan for new channels every month, or every time you notice that a local broadcast goes missing. It’s an easy process, and it’s worth doing for the sake of free OTA TV.

How to Scan (or Rescan) For Channels

Channel scanning on a VIZIO E series TV

Scanning (or rescanning) for channels is mostly an automated process. All you have to do set that process in motion through a few simple steps. And while these steps are different for each TV, the process is pretty similar on every TV out there.

  1. Make sure your TV is connected to an antenna.
  2. Press the “Menu” button on your remote control. If you don’t have a remote, your TV should have a built-in “Menu” button.
  3. Find and select the “Channel Scan” option in your TV’s menu. This option is sometimes labeled “Rescan,” “Tune,” or “Auto-tune.”
  4. If you can’t find the “Channel Scan” option, dig through the TV’s “Settings,” “Tools,” “Channels,” or “Options” menu. On some TVs, you have to press the “Input” button and go to “Antenna.”
  5. Once your TV starts scanning for channels, find something to do. Channel scanning can take upwards of 10 minutes.
  6. When scanning is complete, your TV will either display how many channels are available or drop you back into a broadcast.
  7. Still missing some channels? Try running another scan, or use Mohu’s website to double-check what channels are available in your area. You may need to move your antenna for better reception, too.

If you’re having trouble finding the “Channel Scan” option on your TV, then it’s time to consult the manual. You can usually find a manual by searching the web for the TV’s make and model along with the word “manual.”

Why Can’t My TV Automatically Scan for Channels?

Admittedly, this is a clunky, somewhat annoying process. If radios don’t need to perform tedious rescans, then why can’t TVs automatically scan for channels?

Well, they do—kind of. Scanning (or rescanning) is an automated process; you’re just forcing your TV to enter that process. The reason why your TV doesn’t automatically scan for new channels without your permission is that, well, that would be obnoxious and interfere with your TV watching.

A bunch of broadcasting towers flanked by a beautiful sunset.

Remember, we’re dealing with 20-year-old technology. There’s nothing wrong with it; it’s just got a few quirks. One of those quirks is that, while a TV is scanning, it can’t be used to watch television. If your TV routinely scanned for new channels without your permission, you’d have to deal with random 10-minute bouts of silence every once and awhile. It could even happen while you’re watching an important soap opera or football game.

If you’re wondering why your radio doesn’t need to perform automatic scans, that’s because it’s easy to tune a radio on the fly. A good radio signal is filled with a mix of loud and quiet parts (music), while a bad signal is filled with monotonous static or silence. So, most radios have a built-in tuning circuit that simply checks the amplitude response of radio frequencies. When you press “next” on your radio, it just runs some frequencies through the tuning circuit and locks in on whatever has a mix of loud and quiet parts.

Don’t Worry; Channel Scanning Will Go Away Soon

As we mentioned earlier, the FCC is transitioning to the ATSC 3.0 broadcast standard. It’s a fascinating change that’s worth looking into. In the next decade, ATSC 3.0 will allow us to watch broadcast TV in 4K on practically any device, including phones, tablets, and cars.

Naturally, channel scanning would be a pain on a handheld device or in a car. As you move around town (or even around your house) frequencies will shift in quality and availability. So, the FCC will eliminate the need for channel scanning in ATSC 3.0. Eventually, you’ll forget that you ever had to sit for 10 minutes in front of your TV while it scans for channels, and this guide will disappear into the ether.

RELATED: ASTC 3.0 Explained: Broadcast TV Is Coming to Your Phone

Profile Photo for Andrew Heinzman Andrew Heinzman
Andrew Heinzman writes for How-To Geek and Review Geek. Like a jack-of-all-trades, he handles the writing and image editing for a mess of tech news articles, daily deals, product reviews, and complicated explainers.
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