Television station
Overview
 
A television station is a business, organisation or other such as an amateur television
Amateur television
Amateur television is the transmission of Broadcast quality video and audio over the wide range of frequencies of allocated for Radio amateur use. ATV is used for non-commercial experimentation, pleasure and public service events...

 (ATV) operator that transmits (broadcasts) content over terrestrial television
Terrestrial television
Terrestrial television is a mode of television broadcasting which does not involve satellite transmission or cables — typically using radio waves through transmitting and receiving antennas or television antenna aerials...

. A television transmission can be by analog television
Analog television
Analog television is the analog transmission that involves the broadcasting of encoded analog audio and analog video signal: one in which the message conveyed by the broadcast signal is a function of deliberate variations in the amplitude and/or frequency of the signal...

 signals or, more recently, by digital television
Digital television
Digital television is the transmission of audio and video by digital signals, in contrast to the analog signals used by analog TV...

. Broadcast television systems standards are set by the government, and these vary around the world. Television stations broadcasting over an anolog system were typically limited to one television channel
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 and...

, but digital television enables them to broadcast subchannels.
Encyclopedia
A television station is a business, organisation or other such as an amateur television
Amateur television
Amateur television is the transmission of Broadcast quality video and audio over the wide range of frequencies of allocated for Radio amateur use. ATV is used for non-commercial experimentation, pleasure and public service events...

 (ATV) operator that transmits (broadcasts) content over terrestrial television
Terrestrial television
Terrestrial television is a mode of television broadcasting which does not involve satellite transmission or cables — typically using radio waves through transmitting and receiving antennas or television antenna aerials...

. A television transmission can be by analog television
Analog television
Analog television is the analog transmission that involves the broadcasting of encoded analog audio and analog video signal: one in which the message conveyed by the broadcast signal is a function of deliberate variations in the amplitude and/or frequency of the signal...

 signals or, more recently, by digital television
Digital television
Digital television is the transmission of audio and video by digital signals, in contrast to the analog signals used by analog TV...

. Broadcast television systems standards are set by the government, and these vary around the world. Television stations broadcasting over an anolog system were typically limited to one television channel
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 and...

, but digital television enables them to broadcast subchannels. The term is normally applied to terrestrial television stations, and not to cable television
Cable television
Cable television is a system of providing television programs to consumers via radio frequency signals transmitted to televisions through coaxial cables or digital light pulses through fixed optical fibers located on the subscriber's property, much like the over-the-air method used in traditional...

 or satellite television
Satellite television
Satellite television is television programming delivered by the means of communications satellite and received by an outdoor antenna, usually a parabolic mirror generally referred to as a satellite dish, and as far as household usage is concerned, a satellite receiver either in the form of an...

 broadcasting.

Television stations usually require a broadcast license
Broadcast license
A broadcast license or broadcast license is a specific type of spectrum license that grants the licensee the privilege to use a portion of the radio frequency spectrum in a given geographical area for broadcasting purposes. The licenses are generally straddled with additional restrictions that...

 from a government agency
Government agency
A government or state agency is a permanent or semi-permanent organization in the machinery of government that is responsible for the oversight and administration of specific functions, such as an intelligence agency. There is a notable variety of agency types...

 which set many requirements and limitations on the station. The United States television license will, for example, define the broadcast range a geographic area that the station is limited to and allocate the broadcast frequency
Frequency allocation
Use of radio frequency bands of the electromagnetic spectrum is regulated by governments in most countries, in a Spectrum management process known as frequency allocation or spectrum allocation. Radio propagation does not stop at national boundaries...

 of the radio spectrum
Radio spectrum
Radio spectrum refers to the part of the electromagnetic spectrum corresponding to radio frequencies – that is, frequencies lower than around 300 GHz ....

 for that station's transmissions, and places limits on what types of television program
Television program
A television program , also called television show, is a segment of content which is intended to be broadcast on television. It may be a one-time production or part of a periodically recurring series...

s can be programmed  for broadcast and requires a station to broadcast a minimum amount of certain programs like public affairs (broadcasting)
Public affairs (broadcasting)
Public affairs, a broadcasting industry term, refers to television programs which focuses on matters of politics and public policy. Among commercial broadcasters, such programs are often only to satisfy Federal Communications Commission regulatory expectations and are not scheduled in prime time...

, besides many other conditions.

Most commercial television
Commercial Television
Commercial Television was the third free-to-air broadcast television station in Hong Kong. It first went on air in 1975, and ceased transmissions in 1978.-History:...

 stations are owned independently, but many are either affiliate
Affiliate
An affiliate is a commercial entity with a relationship with a peer or a larger entity.- Corporate structure :A corporation may be referred to as an affiliate of another when it is related to it but not strictly controlled by it, as with a subsidiary relationship, or when it is desired to avoid...

d with a television network
Television network
A television network is a telecommunications network for distribution of television program content, whereby a central operation provides programming to many television stations or pay TV providers. Until the mid-1980s, television programming in most countries of the world was dominated by a small...

 or are owned-and-operated (O&O) by a television network. Another form a television station may take is non-commercial educational
Non-commercial educational
The term non-commercial educational applies to a radio station or TV station that does not accept on air advertisements , as defined in the United States by the Federal Communications Commission . NCE stations do not pay broadcast license fees for their non-profit uses of the radio spectrum...

 (NCE) and considered public broadcasting
Public broadcasting
Public broadcasting includes radio, television and other electronic media outlets whose primary mission is public service. Public broadcasters receive funding from diverse sources including license fees, individual contributions, public financing and commercial financing.Public broadcasting may be...

. To avoid concentration of media ownership
Concentration of media ownership
Concentration of media ownership refers to a process whereby progressively fewer individuals or organizations control increasing shares of the mass media...

 of television stations, government regulations in most countries around the world generally limit the ownership of television stations by television networks or other media operators, but these regulations vary considerably. Some countries have set up nationwide television networks, in which individual television stations act mere as repeater
Repeater
A repeater is an electronic device that receives asignal and retransmits it at a higher level and/or higher power, or onto the other side of an obstruction, so that the signal can cover longer distances.-Description:...

s of nationwide programs
Television program
A television program , also called television show, is a segment of content which is intended to be broadcast on television. It may be a one-time production or part of a periodically recurring series...

. In those countries, the local television station has no station identification
Station identification
Station identification is the practice of radio or television stations or networks identifying themselves on air, typically by means of a call sign or brand name...

 and, from a consumer's point of view, there is no practical distinction between a network and a station, with only small regional changes in programming, such as local television news.

Transmission

To broadcast its programs, a television station requires operators
Operator (profession)
An operator is a professional designation used in various industries, including broadcasting , computing, customer service, physics, and construction. Operators are day-to-day end users of systems, that may or may not be mission-critical, but are typically managed and maintained by technicians or...

 to operate equipment, a transmitter or radio antenna
Antenna (radio)
An antenna is an electrical device which converts electric currents into radio waves, and vice versa. It is usually used with a radio transmitter or radio receiver...

, which is often located at the highest point available in the transmission area, such as on a summit
Summit (topography)
In topography, a summit is a point on a surface that is higher in elevation than all points immediately adjacent to it. Mathematically, a summit is a local maximum in elevation...

, the top of a high skyscraper
Skyscraper
A skyscraper is a tall, continuously habitable building of many stories, often designed for office and commercial use. There is no official definition or height above which a building may be classified as a skyscraper...

, or on a tall radio tower
Radio masts and towers
Radio masts and towers are, typically, tall structures designed to support antennas for telecommunications and broadcasting, including television. They are among the tallest man-made structures...

. To get a signal from the master control
Master control
Master control is the technical hub of a broadcast operation common among most over-the-air television stations and television networks. It is distinct from a production control room in television studios where the activities such as switching from camera to camera are coordinated...

 room to the transmitter, a studio/transmitter link
Studio/transmitter link
A studio-transmitter link sends a radio station's or television station's audio and video from the broadcast studio to a radio transmitter or television transmitter in another location....

 (STL) is used. The link can be either by radio or T1
Digital Signal 1
Digital signal 1 is a T-carrier signaling scheme devised by Bell Labs. DS1 is a widely used standard in telecommunications in North America and Japan to transmit voice and data between devices. E1 is used in place of T1 outside North America, Japan, and South Korea...

/E1. A transmitter/studio link
Transmitter/studio link
The transmitter/studio link of a radio station or television station is a return link which sends telemetry data from the remotely-located radio transmitter or television transmitter back to the studio for monitoring purposes...

 (TSL) may also send telemetry
Telemetry
Telemetry is a technology that allows measurements to be made at a distance, usually via radio wave transmission and reception of the information. The word is derived from Greek roots: tele = remote, and metron = measure...

 back to the station, but this may be embed
Distributed generation
Distributed generation, also called on-site generation, dispersed generation, embedded generation, decentralized generation, decentralized energy or distributed energy, generates electricity from many small energy sources....

ded in subcarrier
Subcarrier
A subcarrier is a separate analog or digital signal carried on a main radio transmission, which carries extra information such as voice or data. More technically, it is an already-modulated signal, which is then modulated into another signal of higher frequency and bandwidth...

s of the main broadcast. Stations which retransmit or simulcast another may simply pick-up that station over-the-air
Terrestrial television
Terrestrial television is a mode of television broadcasting which does not involve satellite transmission or cables — typically using radio waves through transmitting and receiving antennas or television antenna aerials...

, or via STL or satellite. The license usually specifies which other station is it allowed to carry.

VHF stations often have very tall antennas due to their long wavelength
Wavelength
In physics, the wavelength of a sinusoidal wave is the spatial period of the wave—the distance over which the wave's shape repeats.It is usually determined by considering the distance between consecutive corresponding points of the same phase, such as crests, troughs, or zero crossings, and is a...

, but require much less effective radiated power
Effective radiated power
In radio telecommunications, effective radiated power or equivalent radiated power is a standardized theoretical measurement of radio frequency energy using the SI unit watts, and is determined by subtracting system losses and adding system gains...

 (ERP), and therefore use much less transmitter power output
Transmitter power output
In radio transmission, transmitter power output is the actual amount of power of radio frequency energy that a transmitter produces at its output....

, also saving on the electricity
Electricity
Electricity is a general term encompassing a variety of phenomena resulting from the presence and flow of electric charge. These include many easily recognizable phenomena, such as lightning, static electricity, and the flow of electrical current in an electrical wire...

 bill
Invoice
An invoice or bill is a commercial document issued by a seller to the buyer, indicating the products, quantities, and agreed prices for products or services the seller has provided the buyer. An invoice indicates the buyer must pay the seller, according to the payment terms...

 and emergency backup generators. In North America
North America
North America is a continent wholly within the Northern Hemisphere and almost wholly within the Western Hemisphere. It is also considered a northern subcontinent of the Americas...

, full-power stations on band I
Band I
Band I is the name of a radio frequency range within the very high frequency part of the electromagnetic spectrum.Band I ranges from 47 to 88 MHz, and it is primarily used for radio and television broadcasting....

 (channels 2 to 6) are generally limited to 100 kW analog video (VSB) and 10 kW analog audio (FM
FM broadcasting
FM broadcasting is a broadcasting technology pioneered by Edwin Howard Armstrong which uses frequency modulation to provide high-fidelity sound over broadcast radio. The term "FM band" describes the "frequency band in which FM is used for broadcasting"...

), or 45 kW digital (8VSB
8VSB
8VSB is the modulation method used for broadcast in the ATSC digital television standard. ATSC and 8VSB modulation is used primarily in North America; in contrast, the DVB-T standard uses COFDM....

) ERP. Stations on band III
Band III
Band III is the name of a radio frequency range within the very high frequency part of the electromagnetic spectrum.Band III ranges from 174 to 230 MHz, and it is primarily used for radio and television broadcasting...

 (channels 7 to 13) can go up by 5dB
Decibel
The decibel is a logarithmic unit that indicates the ratio of a physical quantity relative to a specified or implied reference level. A ratio in decibels is ten times the logarithm to base 10 of the ratio of two power quantities...

(W
Watt
The watt is a derived unit of power in the International System of Units , named after the Scottish engineer James Watt . The unit, defined as one joule per second, measures the rate of energy conversion.-Definition:...

) to 316 kW video, 31.6 kW audio, or 160 kW digital. Low-VHF stations are often subject to long-distance reception just as with FM. There are no stations on Channel 1.

UHF, by comparison, has a much shorter wavelength, and thus requires a shorter antenna, but also higher power. North American stations can go up to 5000 kW ERP for video and 500 kW audio, or 1000 kW digital. Low channels travel further than high ones at the same power, but UHF does not suffer from as much electromagnetic interference
Electromagnetic interference
Electromagnetic interference is disturbance that affects an electrical circuit due to either electromagnetic induction or electromagnetic radiation emitted from an external source. The disturbance may interrupt, obstruct, or otherwise degrade or limit the effective performance of the circuit...

 and background "noise" as VHF, making it much more desirable for TV. Despite this, in the U.S., the Federal Communications Commission
Federal Communications Commission
The Federal Communications Commission is an independent agency of the United States government, created, Congressional statute , and with the majority of its commissioners appointed by the current President. The FCC works towards six goals in the areas of broadband, competition, the spectrum, the...

 (FCC) is taking another large portion of this band (channels 52 to 69) away, in contrast to the rest of the world, which has been taking VHF instead. This means that some stations left on VHF will be harder to receive after the analog shutdown. Since at least 1974, there are no stations on channel 37
Channel 37
Channel 37 is an unused television channel in countries using the M and N broadcast television system standards. Channel 37 occupies a band of UHF frequencies from 608 to 614 MHz, frequencies that are particularly important to radio astronomy...

 in North America for radio astronomy
Radio astronomy
Radio astronomy is a subfield of astronomy that studies celestial objects at radio frequencies. The initial detection of radio waves from an astronomical object was made in the 1930s, when Karl Jansky observed radiation coming from the Milky Way. Subsequent observations have identified a number of...

 purposes.

Program production

Most television stations are commercial broadcasting
Commercial broadcasting
Commercial broadcasting is the broadcasting of television programs and radio programming by privately owned corporate media, as opposed to state sponsorship...

 enterprises which are structured in a variety of ways to generate revenue
Revenue
In business, revenue is income that a company receives from its normal business activities, usually from the sale of goods and services to customers. In many countries, such as the United Kingdom, revenue is referred to as turnover....

 from television commercials. They may be an independent station
Independent station
An independent station is in the category of television terminology used to describe a television station broadcasting in the United States or Canada that is not affiliated with any television network....

 or part of a broadcasting network, or some other structure. They can produce some or all of their programs or buy some broadcast syndication programming for or all of it from other stations or independent production companies.

Many stations have some sort of television studio
Television studio
A television studio is an installation in which a video productions take place, either for the recording of live television to video tape, or for the acquisition of raw footage for post-production. The design of a studio is similar to, and derived from, movie studios, with a few amendments for the...

, which on major-network stations is often used for newscasts or other local programming
Local programming
The term Local Programme, Local Programming, Local Content or Local Television refers to a television programme made by a television station or independent television producer for broadcast only within the station's transmission area or television market...

. There is usually a news department
Departmentalization
Departmentalization refers to the process of grouping activities into departments.Division of labour creates specialists who need coordination. This coordination is facilitated by grouping specialists together in departments....

, where journalist
Journalist
A journalist collects and distributes news and other information. A journalist's work is referred to as journalism.A reporter is a type of journalist who researchs, writes, and reports on information to be presented in mass media, including print media , electronic media , and digital media A...

s gather information. There is also a section where electronic news-gathering (ENG) operations are based, receiving remote broadcast
Remote broadcast
In broadcast engineering, a remote broadcast is broadcasting done from a location away from a formal television studio and is considered an electronic field production . A remote pickup unit is usually used to transmit the audio and/or video back to the television station, where it joins the...

s via remote pickup unit
Remote pickup unit
A remote pickup unit or RPU is a radio system using special radio frequencies set aside for electronic news gathering and remote broadcasting. It can also be used for other types of point-to-point radio links....

 or satellite TV. Outside broadcasting
Outside broadcasting
Outside broadcasting is the electronic field production of television or radio programmes from a mobile remote broadcast television studio. Professional video camera and microphone signals come into the production truck for processing, recording and possibly transmission...

 vans, production truck
Production truck
Television Production trucks were developed to take television studios on the road so video productions could be made at distant locations for a remote broadcast, outside broadcasting , electronic field production with multiple-camera setup and a support of a number of different technologies to...

s, or SUVs with electronic field production
Electronic field production
Electronic field production is a television industry term referring to a video production which takes place in the field, outside of a formal television studio, in a practical location or special venue...

 (EFP) equipment are sent out with reporters, who may also bring back news stories on video tape rather than sending them back live
Live television
Live television refers to a television production broadcast in real-time, as events happen, in the present. From the early days of television until about 1958, live television was used heavily, except for filmed shows such as I Love Lucy and Gunsmoke. Video tape did not exist until 1957...

.

To keep pace with technology United States television stations have been replacing operators
Operator (profession)
An operator is a professional designation used in various industries, including broadcasting , computing, customer service, physics, and construction. Operators are day-to-day end users of systems, that may or may not be mission-critical, but are typically managed and maintained by technicians or...

 with broadcast automation
Broadcast automation
Broadcast automation incorporates the use of broadcast programming technology to automate broadcasting operations. Used either at a broadcast network, radio station or a television station, it can run a facility in the absence of a human operator...

 systems to increase profits in recent years.

Stations not affiliate
Affiliate
An affiliate is a commercial entity with a relationship with a peer or a larger entity.- Corporate structure :A corporation may be referred to as an affiliate of another when it is related to it but not strictly controlled by it, as with a subsidiary relationship, or when it is desired to avoid...

d with major television network
Television network
A television network is a telecommunications network for distribution of television program content, whereby a central operation provides programming to many television stations or pay TV providers. Until the mid-1980s, television programming in most countries of the world was dominated by a small...

s generally do not air to the public, or much other television program
Television program
A television program , also called television show, is a segment of content which is intended to be broadcast on television. It may be a one-time production or part of a periodically recurring series...

ming. Some stations (known as repeater
Repeater
A repeater is an electronic device that receives asignal and retransmits it at a higher level and/or higher power, or onto the other side of an obstruction, so that the signal can cover longer distances.-Description:...

s or translators
Broadcast relay station
A broadcast relay station, relay transmitter, broadcast translator , rebroadcaster , or repeater is a broadcast transmitter which relays, repeats, or reflects the signal of another radio station or television station, usually to an area not covered by the signal of the originating station...

) only simulcast
Simulcast
Simulcast, shorthand for "simultaneous broadcast", refers to programs or events broadcast across more than one medium, or more than one service on the same medium, at the same time. For example, Absolute Radio is simulcast on both AM and on satellite radio, and the BBC's Prom concerts are often...

 another, usually the programmes seen on its owner's flagship station, and have no television studio or production facilities of their own. This is common in developing countries
Developing country
A developing country, also known as a less-developed country, is a nation with a low level of material well-being. Since no single definition of the term developing country is recognized internationally, the levels of development may vary widely within so-called developing countries...

. Low-power stations typically also fall into this category worldwide.

Most stations which are not simulcast
Simulcast
Simulcast, shorthand for "simultaneous broadcast", refers to programs or events broadcast across more than one medium, or more than one service on the same medium, at the same time. For example, Absolute Radio is simulcast on both AM and on satellite radio, and the BBC's Prom concerts are often...

 produce their own station identification
Station identification
Station identification is the practice of radio or television stations or networks identifying themselves on air, typically by means of a call sign or brand name...

s, using digital alien TV graphics. TV stations may also advertise on or provide weather (or news) services to local radio station
Radio station
Radio broadcasting is a one-way wireless transmission over radio waves intended to reach a wide audience. Stations can be linked in radio networks to broadcast a common radio format, either in broadcast syndication or simulcast or both...

s, particularly co-owned sister station
Sister station
In broadcasting, sister stations or sister channels are radio and/or television stations operated by the same ownership....

s. This may be a barter
Barter
Barter is a method of exchange by which goods or services are directly exchanged for other goods or services without using a medium of exchange, such as money. It is usually bilateral, but may be multilateral, and usually exists parallel to monetary systems in most developed countries, though to a...

 in some cases.

See also

  • Class A television service
    Class A television service
    The class A television service is a system for regulating some low-power television stations in the United States. Class A stations are denoted by the broadcast callsign suffix "-CA" or "-CD" , although very many analog -CA stations have a digital companion channel that was assigned the -LD...

  • Digital television transition
    Digital television transition
    The digital television transition is the process in which analog television broadcasting is converted to and replaced by digital television. This primarily involves both TV stations and over-the-air viewers; however it also involves content providers like TV networks, and cable television...

  • Fernsehsender Paul Nipkow
    Fernsehsender Paul Nipkow
    The Fernsehsender "Paul Nipkow" Berlin was a television station in Germany. It was on the air from March 22, 1935 until it was shut down in 1944. Its headquarters were in Berlin, Germany. It was named after Paul Nipkow, the inventor of the Nipkow disk...

    : the first television station in Germany
  • KTTV
    KTTV
    KTTV, channel 11, is an owned-and-operated television station of the News Corporation-owned Fox Broadcasting Company, located in Los Angeles, California. Serving the vast Los Angeles metropolitan area, KTTV is a sister station to KCOP , Los Angeles' MyNetworkTV station...

  • List of European television stations
  • List of North American broadcast station classes
  • Low-power broadcasting
    Low-power broadcasting
    Low-power broadcasting is electronic broadcasting at very low power and low cost, to a small community area.The terms "low-power broadcasting" and "micropower broadcasting" should not be used interchangeably, because the markets are not the same...

  • Must carry
  • Significantly viewed out of market TV stations in the United States
    Significantly viewed out of market TV stations in the United States
    Significantly viewed are television stations determined by the Federal Communications Commission to be local stations that have a significant viewership outside of their Nielsen designated market area...

The source of this article is wikipedia, the free encyclopedia.  The text of this article is licensed under the GFDL.
 
x
OK