If you don't have an antenna plugged into your television, you're missing out on free channels you could be watching in high definition. Many people who cut the cable cord over the past year to save money are missing an opportunity to get many of the channels they used to pay for.

But which TV antenna is right for you?

If you're shopping on Amazon, you'll see dozens, if not hundreds, of antennas for sale for $20 and up. You'll also see antenna manufacturers making outrageous claims about their products that just aren't true.

"I've seen claims of over 1,000 miles. That's absolutely fraudulent," said Antennas Direct founder Richard Schneider. "There's just no way you can expect a reliable reception."

Getting those channels from the stations to your home television sets requires a line of sight through the antenna. Hills, buildings, trees, and the curvature of the earth prevents channels from reaching an indoor antenna.

"A normal person should never expect reception reliably, more than 70-80 miles and that's with an outdoor antenna," Schneider said. "With an indoor antenna, I'd say 30-40 miles may be pushing it."

TV antennas will not be able to get cable channels, yet some manufacturers advertise antennas that will pick up ESPN, HBO, and other broadcasters only available on cable, satellite, or pay-TV sources.

TV antennas are also often marketed as 4K and 8K antennas, but broadcasting that technology isn't available yet. So beware claims from what Schneider describes as "snake oil salesmen."

If you are looking to buy a TV antenna, Schneider says there are a few things you should know to get the best reception possible.

"Elevation is your friend. The higher you get the antenna, the more successful and more reliable it's going to be," he said. "If you're less than 30 miles from the transmitting towers, you can use an indoor antenna. Try to get it near a window and use the Antenna Point app and get it on a window that's on the side of the house that's facing the transmitting tower."

The Antenna Point app is free for iOS and Android devices. Using your precise location, the app will show on a map the location of all of the TV transmitters in your area.

Schneider also says an amplified antenna that you plug into an electrical socket may not be of any help at all. If the antenna cannot "see" the tower at all, amplified antennas cannot make it suddenly appear. Amplified antennas may indeed help if you are using one antenna for multiple TVs or if there is a long cable between the antenna and the TV.

Watch the full interview with Schneider online.