From Wikipedia, the free encyclopedia
Broadcast TV is typically disseminated via
radio transmissions on designated channels in the 54–890
megahertz frequency band[1]. Signals are now often transmitted with
stereo and/or
surround sound in many countries. Until the 2000s broadcast TV programs were generally recorded and transmitted as an
analog signal, but in recent years public and commercial broadcasters have been progressively introducing
digital television broadcasting technology.
A standard television set comprises multiple internal
electronic circuits, including those for
receiving and decoding broadcast signals. A visual
display device which lacks a tuner is properly called a
monitor, rather than a television. A television system may use different technical standards such as
digital television (DTV) and
high-definition television (HDTV). Television systems are also used for surveillance, industrial process control, and guiding of weapons, in places where direct observation is difficult or dangerous.
Amateur television (
ham TV or
ATV) is also used for experimentation, pleasure and public service events by
amateur radio operators. Ham TV stations were on the air in many cities before commercial TV stations came on the air.
[2]
History
In its early stages of development, television employed a combination of
optical, mechanical and
electronic technologies to capture, transmit and display a visual image. By the late 1920s, however, those employing only optical and electronic technologies were being explored. All modern television systems rely on the latter, although the knowledge gained from the work on mechanical-dependent systems was crucial in the development of fully electronic television.
American family watching TV, 1958
The first time images were transmitted electrically via early mechanical
fax machines, including the
pantelegraph, developed in the late 1800s. The concept of electrically-powered transmission of television images in motion, was first sketched in 1878 as the
telephonoscope, shortly after the invention of the
telephone. At the time, it was imagined by early science fiction authors, that someday that
light could be transmitted over wires, as sounds were.
The idea of using
scanning to transmit images was put to actual practical use in 1881 in the pantelegraph, through the use of a
pendulum-based scanning mechanism. From this period forward, scanning in one form or another, has been used in nearly every image transmission technology to date, including television. This is the concept of "
rasterization", the process of converting a visual image into a stream of electrical pulses.
In 1884
Paul Gottlieb Nipkow, a 20-year old university student in Germany, patented the first electromechanical television system which employed a
scanning disk, a spinning disk with a series of holes spiraling toward the center, for rasterization. The holes were spaced at equal
angular intervals such that in a single rotation the disk would allow light to pass through each hole and onto a light-sensitive
selenium sensor which produced the electrical pulses. As an image was focused on the rotating disk, each hole captured a horizontal "slice" of the whole image.
Nipkow's design would not be practical until advances in
amplifier tube technology became available. The device was only useful for transmitting still "
halftone" images — represented by equally spaced dots of varying size — over
telegraph or
telephone lines.
[citation needed] Later designs would use a rotating mirror-drum scanner to capture the image and a
cathode ray tube (CRT) as a display device, but moving images were still not possible, due to the poor sensitivity of the
selenium sensors. In 1907 Russian scientist
Boris Rosing became the first inventor to use a CRT in the receiver of an experimental television system. He used mirror-drum scanning to transmit simple geometric shapes to the CRT.
[3]
Scottish inventor
John Logie Baird demonstrated the transmission of moving silhouette images in
London in 1925, and of moving,
monochromatic images in 1926. Baird's scanning disk produced an image of 30 lines resolution, just enough to discern a human face, from a double spiral of
lenses.
[citation needed]. Remarkably, in 1927 Baird also invented the world's first
video recording system, "Phonovision" — by modulating the output signal of his
TV camera down to the audio range he was able to capture the signal on a 10-inch wax audio disc using conventional audio recording technology. A handful of Baird's 'Phonovision' recordings survive and these were finally decoded and rendered into viewable images in the 1990s using modern digital signal-processing technology
[4].
In 1926,
Hungarian engineer
Kálmán Tihanyi designed a television system utilizing fully electronic scanning and display elements, and employing the principle of "charge storage" within the scanning (or "camera") tube.
[5][6][7][8]
In 1927,
Philo Farnsworth made the world's first working television system with electronic scanning of both the pickup and display devices,
[9] which he first demonstrated to the press on 1 September 1928.
[9][10]
The first practical use of television was in Germany. Regular television broadcasts began in Germany in 1929 and in 1936 the
Olympic Games in Berlin were broadcast to television stations in Berlin and Leipzig where the public could view the games live.
[11]
Geographical usage
Television introduction by country
1930 to 1939 1940 to 1949 1950 to 1959 1960 to 1969 1970 to 1979 1980 to 1989 1990 to 1999 No data
Content
Programming
Getting TV programming shown to the public can happen in many different ways. After production the next step is to market and deliver the product to whatever markets are open to using it. This typically happens on two levels:
- Original Run or First Run: a producer creates a program of one or multiple episodes and shows it on a station or network which has either paid for the production itself or to which a license has been granted by the producers to do the same.
- Broadcast syndication: this is the terminology rather broadly used to describe secondary programming usages (beyond original run). It includes secondary runs in the country of first issue, but also international usage which may or may not be managed by the originating producer. In many cases other companies, TV stations or individuals are engaged to do the syndication work, in other words to sell the product into the markets they are allowed to sell into by contract from the copyright holders, in most cases the producers.
First run programming is increasing on subscription services outside the U.S., but few domestically produced programs are syndicated on domestic
free-to-air (FTA) elsewhere. This practice is increasing however, generally on digital-only FTA channels, or with subscriber-only first-run material appearing on FTA.
Unlike the U.S., repeat FTA screenings of a FTA network program almost only occur on that network. Also,
affiliates rarely buy or produce non-network programming that is not centred around local events.
Funding
Television sets per 1000 people of the world
1000+ 500–1000 300–500 200–300 100–200 50–100 0–50 No data
Around the globe, broadcast television is financed by either government, advertising, licensing (a form of tax), subscription or any combination of these. To protect revenues, subscription TV channels are usually encrypted to ensure that only subscription payers receive the decryption codes to see the signal. Non-encrypted channels are known as free to air or FTA.
Advertising
Television's broad reach makes it a powerful and attractive medium for
advertisers. Many
television networks and stations sell blocks of broadcast time to advertisers ("sponsors") in order to fund their programming.
United States
Since inception in the U.S. in 1940,
TV commercials have become one of the most effective, persuasive, and popular method of selling products of many sorts, especially consumer goods. U.S.
advertising rates are determined primarily by
Nielsen ratings. The time of the day and popularity of the channel determine how much a television commercial can cost.
.^ Super Bowl Commercials .- Watch Full Episodes of TV Shows Online with blinkx Remote 7 January 2010 23:17 UTC tv.blinkx.com [Source type: General]
Some TV programs also weave advertisements into their shows, a practice begun in film and known as
product placement. For example, a character could be drinking a certain kind of soda, going to a particular
chain restaurant, or driving a certain make of car. (This is sometimes very subtle, where shows have vehicles provided by manufacturers for low cost, rather than wrangling them.) Sometimes a specific brand or
trade mark, or music from a certain artist or group, is used. (This excludes guest appearances by artists, who perform on the show.)
United Kingdom
The TV regulator oversees TV advertising in the United Kingdom. Its restrictions have applied since the early days of commercially funded TV. Despite this, an early TV mogul,
Lew Grade, likened the broadcasting licence as being a "licence to print money". Restrictions mean that the big three national commercial TV channels:
ITV,
Channel 4, and
Five can show an average of only seven minutes of advertising per hour (eight minutes in the peak period). Other broadcasters must average no more than nine minutes (twelve in the peak). This means that many imported TV shows from the US have unnatural breaks where the UK company has edited out the breaks intended for US advertising.
.^ TitanTV can provide programming listings for all types of television services.- TitanTV - Free Customizable TV Listings 7 January 2010 23:17 UTC www.titantv.com [Source type: FILTERED WITH BAYES]
Nor may advertisements be carried in a program designed and broadcast for reception in schools or in any religious service or other devotional program, or during a formal Royal ceremony or occasion. There also must be clear demarcations in time between the programs and the advertisements.
The
BBC, being strictly
non-commercial is not allowed to show advertisements on television in the UK, although it has many advertising-funded channels abroad. The majority of its budget comes from TV licencing (see below) and the sale of content to other broadcasters.
Republic of Ireland
The
Broadcasting Commission of Ireland (
BCI) (
Irish:
Coimisiún Craolacháin na hÉireann)
[15] oversees advertising on television and radio within the
Republic of Ireland on both private and state owned broadcasters. Similar to other European countries, advertising is found on both private and state owned broadcasters. There are some restrictions based on advertising, especially in relation to the advertising of alcohol. Such advertisements are prohibited until after 7pm. Broadcasters in the
Republic of Ireland adhere to broadcasting legislation implemented by the
Broadcasting Commission of Ireland and the
European Union.
.^ Shortcut: Click on the date the first cell of any time header row in the programming grid to immediately be taken back to the current time.- TitanTV - Free Customizable TV Listings 7 January 2010 23:17 UTC www.titantv.com [Source type: FILTERED WITH BAYES]
Taxation or license
.^ TitanTV can provide programming listings for all types of television services.- TitanTV - Free Customizable TV Listings 7 January 2010 23:17 UTC www.titantv.com [Source type: FILTERED WITH BAYES]
For example, some channels may carry no advertising at all and some very little, including:
The
BBC carries no advertising on its UK channels and is funded by an annual licence paid by all households owning a television. This licence fee is set by government, but the BBC is not answerable to or controlled by government and is therefore genuinely independent.
The two main BBC TV channels are watched by almost 90 percent of the population each week and overall have 27 per cent share of total viewing.
[16] This in spite of the fact that 85% of homes are multichannel, with 42% of these having access to 200 free to air channels via satellite and another 43% having access to 30 or more channels via
Freeview.
[17] .^ TV Listings | Contact Us | Terms | Privacy | About Us | Discussion Group | Related Links | Usage Tips | Help .- TitanTV - Free Customizable TV Listings 7 January 2010 23:17 UTC www.titantv.com [Source type: FILTERED WITH BAYES]
When the same sporting event has been presented on both BBC and commercial channels, the BBC always attracts the lion's share of the audience, indicating viewers prefer to watch TV uninterrupted by advertising.
The
Australian Broadcasting Corporation (ABC) carries no advertising (except for internal promotional material) as it is banned under the
ABC Act 1983. The ABC receives its funding from the Australian Government every three years. In the 2008/09 Federal Budget the ABC received A$1.13 Billion
[18]. The funds assist in providing the ABC's Television, Radio, Online and International outputs. The ABC also receives funds from its many ABC Shops across Australia. However funded by the Australian Government the editorial independence of the ABC is ensured through law.
In
France and the
Republic of Ireland government-funded channels carry advertisements yet those who own television sets have to pay an annual tax ("la redevance audiovisuelle").
[19]
Subscription
Some TV channels are partly funded from subscriptions and therefore the signals are encrypted during broadcast to ensure that only paying subscribers have access to the decryption codes. Most subscription services are also funded by advertising.
Genres
Television
genres include a broad range of programming types that entertain, inform, and educate viewers. The most expensive entertainment genres to produce are usually drama and dramatic miniseries. However, other genres, such as historical Western genres, may also have high production costs.
Popular entertainment genres include action-oriented shows such as police, crime, detective dramas, horror, or thriller shows. As well, there are also other variants of the drama genre, such as medical dramas and daytime
soap operas.
Science fiction shows can fall into either the drama or action category, depending on whether they emphasize philosophical questions or high adventure.
.^ Family Guy I Never Met the Dead Man (Comedy, 4/11/1999, TV14) .- TitanTV - Free Customizable TV Listings 7 January 2010 23:17 UTC www.titantv.com [Source type: FILTERED WITH BAYES]
^ Family Guy Death Has a Shadow (Comedy, 1/31/1999, TV14) .- TitanTV - Free Customizable TV Listings 7 January 2010 23:17 UTC www.titantv.com [Source type: FILTERED WITH BAYES]
The least expensive forms of entertainment programming are
game shows,
talk shows,
variety shows, and
reality TV. Game shows show contestants answering questions and solving puzzles to win prizes. Talk shows feature interviews with film, television and music celebrities and public figures. Variety shows feature a range of musical performers and other entertainers such as comedians and magicians introduced by a host or
Master of Ceremonies. There is some crossover between some talk shows and variety shows, because leading talk shows often feature performances by bands, singers, comedians, and other performers in between the interview segments.
Reality TV shows "regular" people (
i.e., not
actors) who are facing unusual challenges or experiences, ranging from arrest by police officers (
COPS) to weight loss (
The Biggest Loser). A variant version of reality shows depicts celebrities doing mundane activities such as going about their everyday life (
Snoop Dogg's Father Hood) or doing manual labour (
Simple Life).
Social aspects
.^ High Definition Television - The 21st Century Non-Starter - Associated Content - associatedcontent.com Associated Content Home Automotive 2 '; } return false;"> .- High Definition Television - The 21st Century Non-Starter - Associated Content - associatedcontent.com 13 January 2010 17:33 UTC www.associatedcontent.com [Source type: General]
^ The creation of television, one of the most important inventions of the 20th century, has it roots firmly planted in the 19th century.- The UnMuseum - Who is the Father of the Television? 7 January 2010 23:17 UTC www.unmuseum.org [Source type: FILTERED WITH BAYES]
^ High Definition Television - The 21st Century Non-Starter .- High Definition Television - The 21st Century Non-Starter - Associated Content - associatedcontent.com 13 January 2010 17:33 UTC www.associatedcontent.com [Source type: General]
There are many aspects of television that can be addressed, including
media violence research.
Environmental aspects
With high
lead content in
CRTs, and the rapid diffusion of new, flat-panel display technologies, some of which (
LCDs) use lamps containing
mercury, there is growing concern about
electronic waste from discarded televisions. Related
occupational health concerns exist, as well, for disassemblers removing copper wiring and other materials from CRTs. Further environmental concerns related to television design and use relate to the devices' increasing
electrical energy requirements.
[20]
In numismatics
Television has had such an impact in today's life, that it has been the main motif for numerous collectors' coins and medals. One of the most recent ones is the
Euro gold and silver commemorative coins (Austria) minted in March 9, 2005. The obverse of the coin shows a "
test pattern", while the reverse shows several milestones in the history of television.
See also
References
- ^ Television Frequency Table, CSGNetwork.com., a Division of Computer Support Group.
- ^ Kowalewski, Anthony, "An Amateur's Television Transmitter", Radio News, April 1938. Early Television Museum and Foundation Website, retrieved 2009-07-19.
- ^ "History of the Cathode Ray Tube". About.com. http://inventors.about.com/od/cstartinventions/a/CathodeRayTube.htm. Retrieved 2009-10-04.
- ^ World's First TV Recordings
- ^ "Hungary - Kálmán Tihanyi's 1926 Patent Application 'Radioskop'". Memory of the World. United Nations Educational, Scientific and Cultural Organization (UNESCO). http://portal.unesco.org/ci/en/ev.php-URL_ID=23240&URL_DO=DO_TOPIC&URL_SECTION=201.html. Retrieved 2008-02-22.
- ^ United States Patent Office, Patent No. 2,133,123, Oct. 11, 1938.
- ^ United States Patent Office, Patent No. 2,158,259, May 16, 1939
- ^ "Vladimir Kosma Zworykin, 1889-1982". Bairdtelevision.com. http://www.bairdtelevision.com/zworykin.html. Retrieved 2009-04-17.
- ^ a b "Philo Taylor Farnsworth (1906-1971)", The Virtual Museum of the City of San Francisco
- ^ Farnsworth, Elma G., Distant Vision: Romance and Discovery on an Invisible Frontier, Salt Lake City, PemberlyKent, 1989, p. 108.
- ^ "TV History". Gadgetrepublic. 2009-05-01. http://www.tvhistory.tv. Retrieved 2009-05-01.
- ^ http://ewh.ieee.org/r2/johnstown/downloads/20090217_IEEE_JST_Trivia_Answers.pdf
- ^ http://www.scitech.mtesz.hu/52tihanyi/flat-panel_tv_en.pdf
- ^ Jon Stewart of "The Daily Show" was mock-outraged at this, saying, "That's what we do!", and calling it a new form of television, "infoganda".
- ^ http://www.bci.ie/
- ^ "viewing statistics in UK". Barb.co.uk. http://www.barb.co.uk/viewingsummary/weekreports.cfm?report=multichannel&requesttimeout=500&flag=viewingsummary. Retrieved 2009-04-17.
- ^ OFCOM quarterly survey
- ^ http://www.abc.net.au/corp/pubs/documents/budget2008-09.pdf
- ^ Ministry of Finance
- ^ "The Rise of the Machines: A Review of Energy Using Products in the Home from the 1970s to Today" (PDF). Energy Saving Trust. July 3, 2006. http://www.energysavingtrust.org.uk/uploads/documents/aboutest/Riseofthemachines.pdf. Retrieved 2007-08-31.
Further reading
- Albert Abramson, The History of Television, 1942 to 2000, Jefferson, NC, and London, McFarland, 2003, ISBN 0786412208.
- Pierre Bourdieu, On Television, The New Press, 2001.
- Tim Brooks and Earle March, The Complete Guide to Prime Time Network and Cable TV Shows, 8th ed., Ballantine, 2002.
- Jacques Derrida and Bernard Stiegler, Echographies of Television, Polity Press, 2002.
- David E. Fisher and Marshall J. Fisher, Tube: the Invention of Television, Counterpoint, Washington, DC, 1996, ISBN 1887178171.
- Steven Johnson, Everything Bad is Good for You: How Today's Popular Culture Is Actually Making Us Smarter, New York, Riverhead (Penguin), 2005, 2006, ISBN 1594481946.
- Jerry Mander, Four Arguments for the Elimination of Television, Perennial, 1978.
- Jerry Mander, In the Absence of the Sacred, Sierra Club Books, 1992, ISBN 0871565099.
- Neil Postman, Amusing Ourselves to Death: Public Discourse in the Age of Show Business, New York, Penguin US, 1985, ISBN 0670804541.
- Evan I. Schwartz, The Last Lone Inventor: A Tale of Genius, Deceit, and the Birth of Television, New York, Harper Paperbacks, 2003, ISBN 0060935596.
- Beretta E. Smith-Shomade, Shaded Lives: African-American Women and Television, Rutgers University Press, 2002.
- Alan Taylor, We, the Media: Pedagogic Intrusions into US Mainstream Film and Television News Broadcasting Rhetoric, Peter Lang, 2005, ISBN 3631518528.
External links