If you’re a Bay Area viewer who watches free, over-the-air television with an antenna, you will need to “rescan” your TV very soon.

According to the Federal Communications Commission (FCC), nearly 1,000 television stations across the country have been, or will be, transitioning to new frequencies. The switches will be made in phases through July.

The current transition phase includes nine local TV stations in the San Francisco-Oakland-San Jose area that are scheduled to change their broadcast frequencies by Friday, May 1. Viewers in the region will need to rescan their TVs to continue receiving these channels via an antenna.

The stations that are changing frequencies are as follows:

— KGO-TV (ABC 7)

— KNTV-TV (NBC 11)

— KRCB-TV (PBS 22)

— KSTS-TV (Telemundo 48)

— KDTV-DT (Univision 14)

— KDTV-CD (CH 28)

— KCNZ-CD (CH 28)

— KRON-TV (CH 4)

–KBCW-TV (CW 44)

The good news is that most viewers won’t need any new devices, equipment or services to rescan their TVs. To rescan, viewers will need their TV remote control or analog TV converter box, then choose “Channel Scan,” “Channel Tuning,” or “Auto Search” in the “Setup” or “Channel” menu (the precise labels vary among manufacturers).

Once you find either the “Channel Scan” or “Channel Tuning” buttons, choose the automatic option to rescan. By rescanning, viewers who watch TV using an antenna will keep their existing channels, and may even discover new channels in their broadcast area.

For further assistance, TV viewers can visit www.fcc.gov/TVrescan or call the consumer helpline at 1-888-CALLFCC (1-888-225-5322) and press 6 to speak with a dedicated help desk representative.

Four other Bay Area TV stations changed their frequencies In a previous transition phase.

Cable and satellite viewers will not be affected as your service provider will do the rescanning.

The reason TV stations are changing frequencies is to make room for new 5G and other mobile broadband services. Nationwide, millions of U.S. households watch national network and local TV programming using an over-the-air antenna.