Television channel

A television channel is a physical or virtual channel over which a television station or television network is distributed. For example, in North America, "channel 2" refers to the broadcast or cable band of 54 to 60 MHz, with carrier frequencies of 55.25 MHz for NTSC analog video (VSB) and 59.75 MHz for analog audio (FM), or 55.31 MHz for digital ATSC (8VSB). Channels may be shared by many different television stations or cable-distributed channels depending on the location and service provider.

Depending on the multinational bandplan for a given region, analog television channels are typically 6, 7, or 8 MHz in bandwidth, and therefore television channel frequencies vary as well. Channel numbering is also different. Digital television channels are the same for legacy reasons, however through multiplexing, each physical radio frequency (RF) channel can carry several digital subchannels. On satellites, each transponder normally carries one channel, however small, independent channels can be used on each transponder, with some loss of bandwidth due to the need for guard bands between unrelated transmissions. ISDB, used in Japan and Brazil, has a similar segmented mode.

Channel

Channel, channels, and similar terms may refer to:

Places

Channel 4

Channel 4 is a British public-service television broadcaster that began transmission on 2 November 1982. Although largely commercially self-funded, it is ultimately publicly owned; originally a subsidiary of the Independent Broadcasting Authority (IBA), the station is now owned and operated by Channel Four Television Corporation, a public body established in 1990, coming into operation in 1993. With the conversion of the Wenvoe transmitter group in Wales to digital on 31 March 2010, Channel 4 became a UK-wide TV channel for the first time.

The channel was established to provide a fourth television service to the United Kingdom in addition to the television licence-funded BBC's two services and the single commercial broadcasting network, ITV.

History

Conception

Before Channel 4 and S4C, Britain had three terrestrial television services: BBC1, BBC2, and ITV. The Broadcasting Act 1980 began the process of adding a fourth, and Channel 4, along with its Welsh counterpart, was formally created by an Act of Parliament in 1982. After some months of test broadcasts, it began scheduled transmissions on 2 November 1982.

John Dee

John Dee (13 July 1527 – 1608 or 1609) was an English mathematician, astronomer, astrologer, occult philosopher, imperialist, and adviser to Queen Elizabeth I. He devoted much of his life to the study of alchemy, divination, and Hermetic philosophy.

Dee straddled the worlds of science and magic just as they were becoming distinguishable. One of the most learned men of his age, he had been invited to lecture on the geometry of Euclid at the University of Paris while still in his early twenties. Dee was an ardent promoter of mathematics and a respected astronomer, as well as a leading expert in navigation, having trained many of those who would conduct England's voyages of discovery.

Simultaneously with these efforts, Dee immersed himself in the worlds of magic, astrology and Hermetic philosophy. He devoted much time and effort in the last thirty years or so of his life to attempting to commune with angels and demons in order to learn the universal language of creation and bring about the pre-apocalyptic unity of mankind. A student of the Renaissance Neo-Platonism of Marsilio Ficino, Dee did not draw distinctions between his mathematical research and his investigations into Hermetic magic, angel summoning and divination. Instead he considered all of his activities to constitute different facets of the same quest: the search for a transcendent understanding of the divine forms which underlie the visible world, which Dee called "pure verities".

Comedy Showcase

Comedy Showcase is a series of one-off comedy specials featuring some of Britain's fledgling comedy talent. Its format is reminiscent of the much earlier Comedy Playhouse. The format was replaced in 2012 by 4Funnies.

Series overview

Episodes

Series 1 (2007)

Series 2 (2009)

Series 3 (2011–2012)

References

External links