Wiktionary
a. (alternative spelling of free to air English)
Wikipedia
Free-to-air (FTA) are television (TV) and radio services broadcast in clear ( unencrypted) form, allowing any person with the appropriate receiving equipment to receive the signal and view or listen to the content without requiring a subscription, other ongoing cost or one-off fee (e.g. Pay-per-view). In the traditional sense, this is carried on terrestrial radio signals and received with an antenna.
FTA also refers to channels and broadcasters providing content for which no subscription is expected, even though they may be delivered to the viewer/listener by another carrier for which a subscription is required, e.g. cable, satellite or the Internet. These carriers may be mandated (or opt) in some geographies to deliver FTA channels even if a premium subscription is not present (providing the necessary equipment is still available), especially where FTA channels are expected to be used for emergency broadcasts, similar to the 112 emergency service provided by mobile phone operators and manufacturers.
Free-to-view (FTV) is, generally, available without subscription but is digitally encoded and may be restricted geographically.
Free-to-air is often used for international broadcasting, making it something of a video equivalent to shortwave radio. Most FTA retailers list free to air channel guides and content available in North America for free to air use.