Sign-off (broadcast)
Encyclopedia
Sign-off is the sequence of operations involved when a radio
or television station
shuts down its transmitter
s and goes off the air for a predetermined period; generally this occurs during the overnight hours. It is the opposite to a sign-on (or startup) which usually takes place at the start of the day.
system just as for other television program
ming, and automatic transmission system
s can cutoff the carrier signal and trigger the actual shutdown of the transmitter by remote control
. Generally, after the carrier signal is cut, the viewer only sees or hears static
.
Both sign-offs and sign-ons have become less common with the increasing prevalence of twenty-four hour a day, seven day a week
broadcasting. They are, however, still conducted by a number of stations around the world, often by stations catering to small-markets or those in less developed countries, or when stations need to shut-down for transmitter maintenance. Another consideration for whether providers shutdown is power consumption; aerial signals, such as those for UHF analog TV transmissions, can require tens of thousands of watt
s of power, making electricity
a major expense, while power consumption would usually be considerably lower for cable and satellite providers.
For broadcasters that do still close for a period each day, the station close most often takes place overnight, during the early hours of the morning. The daily sign-off typically occurs between around 11:00 pm and 2:00 am, and the station will remain closed until about 5:00 am to 7:00 am, although in countries with limited broadcast coverage, sign-off may occur at earlier times, and sign-on later. Sign-off may also vary depending on the day of the week, for example some broadcasters may run for 24 hours on Saturday nights, but sign-off and close during the week when there are lower viewer numbers. Seasonality is also a consideration where some stations/networks stay open for 24-hours during peak times of religious observances.
Many stations, while no longer conducting a sign-off and being off air for a period of time each day, instead run low quality, low cost programming during those times of low viewer numbers. This may include paid programming such as infomercials, old movies
, television, or radio shows, simple weather forecasts
or information services, often backed by public domain
music or local radio stations, low cost news or infotainment
programming from other suppliers, replays of earlier programming, or feeds of local cable TV companies' programming via a fiber optic line to the cable headend. Other broadcasters that are part of a radio
or television network
may run an unedited feed of the network's overnight programming from a central location, without local advertising. Some stations, after doing a sign-off, nonetheless continue to transmit throughout the off-air period on cable/satellite; this transmission may involve a test pattern
, a static image, or text based news items, often with backing music.
While most of these sign-off steps are done as a service to the public, or for advertising reasons, some of them may be required by the government of the country. For example, in the US, the Federal Communications Commission (FCC)
regulations require stations to identify themselves before leaving the air, which usually means they must announce their calls, city of license, and broadcast frequency or channel number.
this was initially due to Government-imposed restrictions on daytime broadcasting hours, and later, due to budgetary constrictions. The eventual relaxation of these rules meant that afternoon closedowns ceased permanently on the ITV
network in October 1972, however the BBC
maintained the practice until late 1986, before commencing a full daytime service. Afternoon closedowns continued in South Korea
until December 2005.
During Holy Week
in the Philippines
, particularly on Holy Thursday, Good Friday
and Black Saturday
, most terrestrial stations remain off air for the entire day, while others may only commence transmission during the late morning or at midday. During Ramadan, RTM, Malaysia's public broadcaster operates TV1 24 hours a day instead of signing-off.
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...
or television station
Television station
A television station is a business, organisation or other such as an amateur television operator that transmits content over terrestrial television. A television transmission can be by analog television signals or, more recently, by digital television. Broadcast television systems standards are...
shuts down its transmitter
Transmitter
In electronics and telecommunications a transmitter or radio transmitter is an electronic device which, with the aid of an antenna, produces radio waves. The transmitter itself generates a radio frequency alternating current, which is applied to the antenna. When excited by this alternating...
s and goes off the air for a predetermined period; generally this occurs during the overnight hours. It is the opposite to a sign-on (or startup) which usually takes place at the start of the day.
Overview
Sign-offs, like sign-ons, vary from country to country, from station to station, and from time to time, however most follow a similar general pattern. Many stations follow the reverse process to their sign-on sequence at the start of the day. Sign-off messages can be initiated by a broadcast automationBroadcast 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...
system just as for 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, and automatic transmission system
Automatic transmission system
An automatic transmission system is an automated system designed to keep a radio transmitter and antenna system running without direct human oversight or attention for long periods.-History:In the early days of radio, an operator, technician or electrical engineer...
s can cutoff the carrier signal and trigger the actual shutdown of the transmitter by remote control
Remote control
A remote control is a component of an electronics device, most commonly a television set, used for operating the television device wirelessly from a short line-of-sight distance.The remote control is usually contracted to remote...
. Generally, after the carrier signal is cut, the viewer only sees or hears static
Static
Static has several meanings:* Static electricity, a net charge of an object** The triboelectric effect, e.g. from shoes rubbing carpet* White noise, a random signal with a flat power spectral density** Noise , a type of radio interference...
.
Both sign-offs and sign-ons have become less common with the increasing prevalence of twenty-four hour a day, seven day a week
24/7
24/7 is an abbreviation which stands for "24 hours a day, 7 days a week", usually referring to a business or service available at all times without interruption...
broadcasting. They are, however, still conducted by a number of stations around the world, often by stations catering to small-markets or those in less developed countries, or when stations need to shut-down for transmitter maintenance. Another consideration for whether providers shutdown is power consumption; aerial signals, such as those for UHF analog TV transmissions, can require tens of thousands of watt
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:...
s of power, making 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...
a major expense, while power consumption would usually be considerably lower for cable and satellite providers.
For broadcasters that do still close for a period each day, the station close most often takes place overnight, during the early hours of the morning. The daily sign-off typically occurs between around 11:00 pm and 2:00 am, and the station will remain closed until about 5:00 am to 7:00 am, although in countries with limited broadcast coverage, sign-off may occur at earlier times, and sign-on later. Sign-off may also vary depending on the day of the week, for example some broadcasters may run for 24 hours on Saturday nights, but sign-off and close during the week when there are lower viewer numbers. Seasonality is also a consideration where some stations/networks stay open for 24-hours during peak times of religious observances.
Many stations, while no longer conducting a sign-off and being off air for a period of time each day, instead run low quality, low cost programming during those times of low viewer numbers. This may include paid programming such as infomercials, old movies
Film
A film, also called a movie or motion picture, is a series of still or moving images. It is produced by recording photographic images with cameras, or by creating images using animation techniques or visual effects...
, television, or radio shows, simple weather forecasts
Weather forecasting
Weather forecasting is the application of science and technology to predict the state of the atmosphere for a given location. Human beings have attempted to predict the weather informally for millennia, and formally since the nineteenth century...
or information services, often backed by public domain
Public domain
Works are in the public domain if the intellectual property rights have expired, if the intellectual property rights are forfeited, or if they are not covered by intellectual property rights at all...
music or local radio stations, low cost news or infotainment
Infotainment
Infotainment is "information-based media content or programming that also includes entertainment content in an effort to enhance popularity with audiences and consumers." It is a neologistic portmanteau of information and entertainment, referring to a type of media which provides a combination of...
programming from other suppliers, replays of earlier programming, or feeds of local cable TV companies' programming via a fiber optic line to the cable headend. Other broadcasters that are part of a radio
Radio network
There are two types of radio networks currently in use around the world: the one-to-many broadcast type commonly used for public information and mass media entertainment; and the two-way type used more commonly for public safety and public services such as police, fire, taxicabs, and delivery...
or 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...
may run an unedited feed of the network's overnight programming from a central location, without local advertising. Some stations, after doing a sign-off, nonetheless continue to transmit throughout the off-air period on cable/satellite; this transmission may involve a test pattern
Test card
A test card, also known as a test pattern in North America and Australia, is a television test signal, typically broadcast at times when the transmitter is active but no program is being broadcast...
, a static image, or text based news items, often with backing music.
Sign-off sequence
The sign-off sequence may include some or all of the following stages, but not necessarily in this order:- An announcement made about the upcoming sign-off to inform the viewers that the station is about to go off-air.
- A station jingleJingleA jingle is a short tune used in advertising and for other commercial uses. The jingle contains one or more hooks and lyrics that explicitly promote the product being advertised, usually through the use of one or more advertising slogans. Ad buyers use jingles in radio and television...
or sloganSloganA slogan is a memorable motto or phrase used in a political, commercial, religious and other context as a repetitive expression of an idea or purpose. The word slogan is derived from slogorn which was an Anglicisation of the Scottish Gaelic sluagh-ghairm . Slogans vary from the written and the...
may be played, accompanied on television with video clips featuring station programming or personalities. A series of program trailersTrailer (film)A trailer or preview is an advertisement or a commercial for a feature film that will be exhibited in the future at a cinema. The term "trailer" comes from their having originally been shown at the end of a feature film screening. That practice did not last long, because patrons tended to leave the...
may also be played. - A prayerPrayerPrayer is a form of religious practice that seeks to activate a volitional rapport to a deity through deliberate practice. Prayer may be either individual or communal and take place in public or in private. It may involve the use of words or song. When language is used, prayer may take the form of...
, hymnHymnA hymn is a type of song, usually religious, specifically written for the purpose of praise, adoration or prayer, and typically addressed to a deity or deities, or to a prominent figure or personification...
, or other religious acknowledgement, particularly in countries with a state religionState religionA state religion is a religious body or creed officially endorsed by the state...
, in theocraciesTheocracyTheocracy is a form of organization in which the official policy is to be governed by immediate divine guidance or by officials who are regarded as divinely guided, or simply pursuant to the doctrine of a particular religious sect or religion....
, and on religious broadcastersReligious broadcastingReligious broadcasting refers to broadcasting by religious organizations, usually with a religious message. Many religious organizations have long recorded content such as sermons and lectures, and have moved into distributing content on their Internet websites.While this article emphasises...
. For example, sign-offs in Malaysia generally include an IslamIslamIslam . The most common are and . : Arabic pronunciation varies regionally. The first vowel ranges from ~~. The second vowel ranges from ~~~...
ic reading from the Quran for up to fifteen minutes and a call for the midnight salah, stations in ThailandThailandThailand , officially the Kingdom of Thailand , formerly known as Siam , is a country located at the centre of the Indochina peninsula and Southeast Asia. It is bordered to the north by Burma and Laos, to the east by Laos and Cambodia, to the south by the Gulf of Thailand and Malaysia, and to the...
typically include a quote from BuddhaGautama BuddhaSiddhārtha Gautama was a spiritual teacher from the Indian subcontinent, on whose teachings Buddhism was founded. In most Buddhist traditions, he is regarded as the Supreme Buddha Siddhārtha Gautama (Sanskrit: सिद्धार्थ गौतम; Pali: Siddhattha Gotama) was a spiritual teacher from the Indian...
, and many stations in the United StatesUnited StatesThe United States of America is a federal constitutional republic comprising fifty states and a federal district...
include a ChristianChristianA Christian is a person who adheres to Christianity, an Abrahamic, monotheistic religion based on the life and teachings of Jesus of Nazareth as recorded in the Canonical gospels and the letters of the New Testament...
prayer or hymn of some type. - A short weather forecast, newscast, or a pre-taped inspirational message known as a sermonetteSermonetteSermonette is a generic term for short, locally-produced inspirational messages that were aired by many U.S. television stations during their sign-on and sign-off periods....
. - A "goodnight" message to viewers or listeners thanking them for their patronage, along with an announcement of the time when the station is scheduled to sign on again.
- A program guide for the following day's programs.
- Ownership information about the station and a list of related organizations.
- Contact information, such as street and mailing addresses, telephone number, email, and website details.
- Technical information provided, such as the call signCall signIn broadcasting and radio communications, a call sign is a unique designation for a transmitting station. In North America they are used as names for broadcasting stations...
, transmitter powerTransmitter power outputIn radio transmission, transmitter power output is the actual amount of power of radio frequency energy that a transmitter produces at its output....
, translators used, transmitter locations, a list of engineerEngineerAn engineer is a professional practitioner of engineering, concerned with applying scientific knowledge, mathematics and ingenuity to develop solutions for technical problems. Engineers design materials, structures, machines and systems while considering the limitations imposed by practicality,...
s, and studio/transmitter links (STL)Studio/transmitter linkA 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....
. - A disclaimerDisclaimerA disclaimer is generally any statement intended to specify or delimit the scope of rights and obligations that may be exercised and enforced by parties in a legally recognized relationship...
that station programming is taped, aired live, or originates from a televisionTelevision networkA 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 radio networkRadio networkThere are two types of radio networks currently in use around the world: the one-to-many broadcast type commonly used for public information and mass media entertainment; and the two-way type used more commonly for public safety and public services such as police, fire, taxicabs, and delivery...
. - Another disclaimer that programs are for personal use only (sometimes with information on copyrightCopyrightCopyright is a legal concept, enacted by most governments, giving the creator of an original work exclusive rights to it, usually for a limited time...
restrictions), and a statement that businesses cannot profit from showing them by applying a cover chargeCover chargeAt bars and nightclubs, or restaurants with live entertainment a flat fee for entry, sometimes known as a cover charge, is made, in addition to payment for food and drink...
for viewing. - A statement of commitment to quality; this may be in the form of a recognized standard, such as the United StatesUnited StatesThe United States of America is a federal constitutional republic comprising fifty states and a federal district...
National Association of BroadcastersNational Association of BroadcastersThe National Association of Broadcasters is a trade association, workers union, and lobby group representing the interests of for-profit, over-the-air radio and television broadcasters in the United States...
' "Seal of Good Practice". - A station identificationStation identificationStation 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...
, including some or all of the television channelTelevision channelA 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...
, AMAmplitude modulationAmplitude modulation is a technique used in electronic communication, most commonly for transmitting information via a radio carrier wave. AM works by varying the strength of the transmitted signal in relation to the information being sent...
or FMFrequency modulationIn telecommunications and signal processing, frequency modulation conveys information over a carrier wave by varying its instantaneous frequency. This contrasts with amplitude modulation, in which the amplitude of the carrier is varied while its frequency remains constant...
frequencyFrequencyFrequency is the number of occurrences of a repeating event per unit time. It is also referred to as temporal frequency.The period is the duration of one cycle in a repeating event, so the period is the reciprocal of the frequency...
, call signCall signIn broadcasting and radio communications, a call sign is a unique designation for a transmitting station. In North America they are used as names for broadcasting stations...
, brandingBrandThe American Marketing Association defines a brand as a "Name, term, design, symbol, or any other feature that identifies one seller's good or service as distinct from those of other sellers."...
, and a clock identClock identA clock ident is a form of television ident that employs a clock displaying the current time with the station logo, typically used before news bulletins and closedown.-Appearance:...
. - On television stations, a video and/or photo montageMontage-Filmmaking:*Montage , a technique which uses rapid editing, special effects and music to present compressed narrative information*Soviet montage theory in the 1920s-Other:* Montage , Documentary television series from 1960s and 1970s...
set to the national anthemNational anthemA national anthem is a generally patriotic musical composition that evokes and eulogizes the history, traditions and struggles of its people, recognized either by a nation's government as the official national song, or by convention through use by the people.- History :Anthems rose to prominence...
or another patriotic piece of music may be played; on radio stations#TVB this would just consist of the music, usually the national anthem. The accompanying television video usually involves images of the national flagNational flagA national flag is a flag that symbolizes a country. The flag is flown by the government, but usually can also be flown by citizens of the country.Both public and private buildings such as schools and courthouses may fly the national flag...
, head of stateHead of StateA head of state is the individual that serves as the chief public representative of a monarchy, republic, federation, commonwealth or other kind of state. His or her role generally includes legitimizing the state and exercising the political powers, functions, and duties granted to the head of...
, militaryMilitaryA military is an organization authorized by its greater society to use lethal force, usually including use of weapons, in defending its country by combating actual or perceived threats. The military may have additional functions of use to its greater society, such as advancing a political agenda e.g...
, national symbols, or other nationalisticNationalismNationalism is a political ideology that involves a strong identification of a group of individuals with a political entity defined in national terms, i.e. a nation. In the 'modernist' image of the nation, it is nationalism that creates national identity. There are various definitions for what...
imagery, particularly on state ownedState ownershipState ownership, also called public ownership, government ownership or state property, are property interests that are vested in the state, rather than an individual or communities....
broadcasters. - The station may display some type of novelty item, such as an animated character, particular to that station or its locale.
- The display of a test pattern, a variation on the station logo, or a black signal, often accompanied by a monotoneMonotoneMonotone refers to a sound, for example speech or music, that has a single unvaried tone.Monotone or monotonicity may also refer to:*Monotone , an open source revision control system*Monotone class theorem, in measure theory...
sound for a short period of time; radio stations may just play a monotone. - A signal to turn off remote transmitterTransmitterIn electronics and telecommunications a transmitter or radio transmitter is an electronic device which, with the aid of an antenna, produces radio waves. The transmitter itself generates a radio frequency alternating current, which is applied to the antenna. When excited by this alternating...
s may be played—this is usually a series of touch tones. Once the transmission has been cut off there will usually only be video staticNoise (video)Noise, in analog video and television, is a random dot pattern of static displayed when no transmission signal is obtained by the antenna receiver of television set and other display devices...
on television stations or radio staticNoise (radio)In radio reception, noise is the superposition of white noise and other disturbing influences on the signal, caused either by thermal noise and other electronic noise from receiver input circuits or by interference from radiated electromagnetic noise picked up by the receiver's antenna...
on radio stations. - Viewers may be warned to remember to turn off their television sets just prior to the transmitter being switched off; these announcements were particularly common in the early days of television, but are still in regular practice in some places, such as RussiaRussiaRussia or , officially known as both Russia and the Russian Federation , is a country in northern Eurasia. It is a federal semi-presidential republic, comprising 83 federal subjects...
.
While most of these sign-off steps are done as a service to the public, or for advertising reasons, some of them may be required by the government of the country. For example, in the US, the Federal Communications Commission (FCC)
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...
regulations require stations to identify themselves before leaving the air, which usually means they must announce their calls, city of license, and broadcast frequency or channel number.
Special cases
In a number of countries closedowns formerly took place during the daytime as well as overnight. In the United KingdomUnited Kingdom
The United Kingdom of Great Britain and Northern IrelandIn the United Kingdom and Dependencies, other languages have been officially recognised as legitimate autochthonous languages under the European Charter for Regional or Minority Languages...
this was initially due to Government-imposed restrictions on daytime broadcasting hours, and later, due to budgetary constrictions. The eventual relaxation of these rules meant that afternoon closedowns ceased permanently on the ITV
ITV
ITV is the major commercial public service TV network in the United Kingdom. Launched in 1955 under the auspices of the Independent Television Authority to provide competition to the BBC, it is also the oldest commercial network in the UK...
network in October 1972, however the BBC
BBC
The British Broadcasting Corporation is a British public service broadcaster. Its headquarters is at Broadcasting House in the City of Westminster, London. It is the largest broadcaster in the world, with about 23,000 staff...
maintained the practice until late 1986, before commencing a full daytime service. Afternoon closedowns continued in South Korea
South Korea
The Republic of Korea , , is a sovereign state in East Asia, located on the southern portion of the Korean Peninsula. It is neighbored by the People's Republic of China to the west, Japan to the east, North Korea to the north, and the East China Sea and Republic of China to the south...
until December 2005.
During Holy Week
Holy Week
Holy Week in Christianity is the last week of Lent and the week before Easter...
in the Philippines
Philippines
The Philippines , officially known as the Republic of the Philippines , is a country in Southeast Asia in the western Pacific Ocean. To its north across the Luzon Strait lies Taiwan. West across the South China Sea sits Vietnam...
, particularly on Holy Thursday, Good Friday
Good Friday
Good Friday , is a religious holiday observed primarily by Christians commemorating the crucifixion of Jesus Christ and his death at Calvary. The holiday is observed during Holy Week as part of the Paschal Triduum on the Friday preceding Easter Sunday, and may coincide with the Jewish observance of...
and Black Saturday
Holy Saturday
Holy Saturday , sometimes known as Easter Eve or Black Saturday, is the day after Good Friday. It is the day before Easter and the last day of Holy Week in which Christians prepare for Easter...
, most terrestrial stations remain off air for the entire day, while others may only commence transmission during the late morning or at midday. During Ramadan, RTM, Malaysia's public broadcaster operates TV1 24 hours a day instead of signing-off.
See also
- DTV transition in the United StatesDTV transition in the United StatesThe DTV transition in the United States was the switchover from analog to exclusively digital broadcasting of free over-the-air television programming...
- Goodnight KiwiGoodnight KiwiThe Goodnight Kiwi, later also called TV Kiwi, is a character in an animated short which has been used to signal the end of nightly broadcasts on Television New Zealand channels. The animation was introduced in 1975 on TV2, and used on South Pacific Television between 1976 and 1980. Between 1980...
- ITV NightscreenITV NightscreenITV Nightscreen is a scheduled programme on the United Kingdom's ITV television network, consisting of a sequence of animated pages of information about ITV's upcoming programmes, features and special events, with an easy listening music soundtrack. The programme is used to fill the station's...
- Dark (broadcasting)Dark (broadcasting)In the broadcasting industry, dark is a term used to describe a radio station or television station that has gone off-the-air for an indefinite period of time, or as defined by the U.S. Federal Communications Commission , a "silent" station...
External links
- TV-Signoffs.com - J. Alan Wall's website devoted to sign-offs and sign-ons of United States television stations
- The Television Close Down And Start Up Blog - A blog devoted to sign-offs and sign-ons from around the world
- TV-Ark