Mainers who use TV antennas will have to rescan their sets Wednesday to continue watching all the channels available in their area.

Three Portland-area TV stations will be changing their frequencies – the paths their signals travel over the airwaves – at 7 a.m. Wednesday. So to get those stations on their new frequencies, people will have to hit the channel scanning function on their sets, sometimes called “channel set up” or “auto tune.” The frequency change does not affect the channel number of each station that appears on TV sets, according to the local stations.

The three stations switching frequencies, according to the Federal Communications Commission, are NBC affiliate WCSH (News Center Maine), CW affiliate WPXT, and Maine Public Television station WMEA. News Center Maine will continue to be found at Channel 6.1, WPXT at 51.1 and WMEA at 26.1.

More than 1,000 stations around the country are having to change frequencies to make room for new 5G and other mobile broadband services over the airwaves, according to the FCC. The other Portland stations that broadcast an over-the-air signal are not switching frequencies, including CBS affiliate WGME, ABC affiliate WMTW and FOX affiliate WPFO.

The change of frequencies does not affect viewers who get these stations via cable, satellite or streaming service, according to the FCC, as their TV providers will handle the change. The change only directly affects people who use an antenna to get an over-the-air TV signal, which local stations are required to transmit. People who purchase and install antennas can watch local stations for free.

For more information about the frequency change, including how to rescan your television to receive over-the-air signals, go to fcc.gov/TVrescan.