Terrestrial television (also known as over-the-air or OTA) is the traditional method of television broadcast signal delivery, by radio waves. Terrestrial television broadcasting dates back to the very beginnings of television as a medium itself with the first long distance public television broadcast from Washington, DC on April 7, 1927. Aside from transmission by high-flying planes moving in a loop using a system developed by Westinghouse called Stratovision, there was virtually no other method of television delivery until the 1950s with the advent of cable television, or community antenna television (CATV). The first non-terrestrial method of delivering television signals that in no way depended on a signal originating from a traditional terrestrial source began with the use of communications satellites during the 1960s and 1970s.
In the United States and most of North America, terrestrial television underwent a revolutionary transformation with the eventual acceptance of the NTSC standard for color television broadcasts in 1953. Later, Europe and the rest of the world either chose between the later PAL and SECAM color television standards, or adopted NTSC.
In addition to the threat from CATV, analog terrestrial television is now also subject to competition from satellite television and distribution of video and film content over the Internet. The technology of digital terrestrial television has been developed as a response to these challenges. The rise of digital terrestrial television, especially HDTV, may mark an end to the decline of broadcast television reception via traditional receiving antennas, which can receive over-the-air HDTV signals.
In North America, terrestrial broadcast television operates on TV channels 2 through 6 (VHF-low band, known as band I in Europe), 7 through 13 (VHF-high band, known as band III elsewhere), and 14 through 69 (UHF television band, elsewhere bands IV and V). Channel numbers represent actual frequencies used to broadcast the television signal. Additionally, television translators and boosters can be used to rebroadcast a terrestrial TV signal using an otherwise unused channel to cover areas with marginal reception. A chart showing the North American television bandplan can be found UK, UHF frequencies were first used in 1964 with the introduction of BBC2. Television broadcasting on VHF frequencies was discontinued in 1983.
In India, where the illiteracy rate is ____ television and radio programmes, when used as part of a larger communication campaign, have successfully increased overall awareness about the dangers of diarrhoeal diseases and different treatments for dehydration.
Shorter materials, such as commercials, need to be broadcast several times each day for three to four months to have an impact.
These broadcasts will be integrated with all the other programmes so that it is used to strengthen and support other communication activities such as face-to-face advising health education talks, or the distribution of printed materials.
TelevisionBroadcasts Limited, commonly known as TVB, is the first wireless commercial television station in Hong Kong.
TVB enjoys an overwhelming dominance on the television market in Hong Kong; however, its programs have often been criticised by some TV viewers for reasons such as "bad taste", "superficiality", "dullness", and "lack of creativity".
To cope with future development and expansion, TelevisionBroadcasts Limited began planning in 1998 to develop in the Tseung Kwan O Industrial Estate a replacement for the old facility at Clearwater Bay.
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