Broadcasttelevision systems (orterrestrial television systems outside the US and Canada) are the encoding or formatting systems for the transmission and reception of terrestrial television signals.

Analog television systems were standardized by theInternational Telecommunication Union (ITU) in 1961,^[1] with each system designated by a letter (A-N) in combination with the color standard used (NTSC,PAL orSECAM) - for example PAL-B, NTSC-M, etc.). These analog systems for TV broadcasting dominated until the 2000s.

With the introduction ofdigital terrestrial television (DTT), they were replaced by four main systems in use around the world:ATSC,DVB,ISDB andDTMB.

Every analog television system bar one began as ablack-and-white system. Each country, faced with local political, technical, and economic issues, later adopted acolor television standard which was grafted onto an existingmonochrome system such asCCIR System M, using gaps in the video spectrum (explained below) to allow color transmission information to fit in the existing channels allotted. The grafting of the color transmission standards onto existing monochrome systems permitted existing monochrome television receivers predating the changeover to color television to continue to be operated as monochrome television. Because of this compatibility requirement, color standards added a second signal to the basic monochrome signal, which carries the color information. The color information is calledchrominance with the symbol C, while the black and white information is called theluminance with the symbol Y. Monochrome television receivers only display the luminance, while color receivers process both signals. Though in theory any monochrome system could be adopted to a color system, in practice some of the original monochrome systems proved impractical to adapt to color and were abandoned when the switch to color broadcasting was made. All countries used one of three color standards: NTSC, PAL, or SECAM. For example, CCIR System M was often used in conjunction with NTSC standard, to provide color analog television and the two together were known as NTSC-M.

A number of experimental and broadcast pre-WW2 systems were tested. The first ones were mechanically based and of very low resolution, sometimes with no sound. Later TV systems were electronic, and usually mentioned by their line number:375-line (used in Germany, Italy, US),405-line (used in the UK),441-line (used in Germany, France, Italy, US) or567-line (used in the Netherlands). These systems were mostly experimental and national, with no defined international standards, and didn't resume broadcasting after the war. An exception was the UK 405-line system, that resumed broadcasts and was the first to be standardized by ITU asSystem A, remaining in operation until 1985.

On an international conference inStockholm in 1961, theInternational Telecommunication Union designated standards for broadcast television systems (ITU System Letter Designation).^[1] Each standard is designated by a letter (A-M).

OnVHFbands I,II andIII the405,625 and819-line systems could be used:

• A – 405-line system, 5 MHz video bandwidth
• B – 625-line system, 7 MHz video bandwidth
• C – Belgian 625-line system, 7 MHz video bandwidth
• D –I.B.T.O. 625-line system, 8 MHz video bandwidth
• E – French 819-line system, 14 MHz video bandwidth
• F – Belgian 819-line system, 7 MHz video bandwidth

OnUHF bandsBands IV andV only 625-line systems were adopted, with the difference being transmission parameters like channel bandwidth.

• G – 625-line system, 5 MHz video bandwidth
• H – 625-line system, 5 MHz video bandwidth
• I – 625-line system, 5.5 MHz video bandwidth
• K – 625-line system, 6 MHz video bandwidth
• L – 625-line system, 6 MHz video bandwidth

Following further conferences and the introduction of color television, by 1966^[2] each standard was designated by a letter (A-M) in combination with a color standard (NTSC, PAL, SECAM). This completely specifies all of the monaural analog television systems in the world (for example, PAL-B, NTSC-M, etc.).

The following table gives the principal characteristics of each standard.^[2] Except forlines andframe rates, other units aremegahertz (MHz).

• Also see:television channel frequencies

A

EarlyUnited Kingdom andIreland VHF system (B&W only). First electronic TV system, introduced in 1936. Vestigial sideband filtering introduced in 1949. Discontinued on 23 November 1982 in Ireland and on 2 January 1985 in the UK.^[4][5]

B

VHF-only in most Western European countries (combined with system G and H on UHF); VHF and UHF inAustralia. Originally known as the Gerber standard.^[6]

C

Early VHF system; used only inBelgium,Italy, theNetherlands, andLuxembourg, as a compromise between Systems B and L. Discontinued in 1977.^[5]

D

The first 625-line system. Used on VHF only in most countries (combined with system K on UHF); VHF and UHF inChina.

E

EarlyFrench VHF system (B&W only); very good (nearHDTV) picture quality but uneconomical use of bandwidth. Sound carrier separation +11.15 MHz on odd numbered channels, -11.15 MHz on even numbered channels. Discontinued in 1984 (France) and 1985 (Monaco).^[7]

F

Early VHF system used only in Belgium and Luxembourg; allowed French 819-linetelevision programming to be broadcast on the 7 MHz VHF channels used in those countries, at a substantial cost in horizontal resolution. Discontinued in 1968 (Belgium) and 1971 (Luxembourg).^[5]

G

UHF only; used in countries withSystem B on VHF, except Australia.

H

UHF only; used only in Belgium, Luxembourg, and the Netherlands. Similar to System G with a 1.25 MHz vestigal sideband.

I

Used in theUK,Ireland,Southern Africa,Macau,Hong Kong, andFalkland Islands.

J

Used inJapan (see system M below). Identical to system M except that a different black level of 0IRE is used instead of 7.5 IRE. Although the ITU specified a frame rate of 30 fields, 29.97 was adopted with the introduction of NTSC color to minimize visual artifacts. Discontinued in 2012, when Japan transitioned todigital.

K

UHF only; used in countries with system D on VHF, except China, and identical to it in most respects.

K1

Used only inFrench overseas departments and territories.

L

Used only inFrance. On VHF Band 1 only, the audio is at −6.5 MHz. Discontinued in 2011, when France transitioned todigital. It was the last system to use positive video modulation and AM sound.

M

Used in most of theAmericas andCaribbean (exceptArgentina,Paraguay,Uruguay, andFrench Guiana),Myanmar,South Korea,Taiwan,Philippines (all NTSC-M),Brazil (PAL-M),Vietnam,Cambodia, andLaos (all SECAM-M). Although the ITU specified a frame rate of 30 fields, 29.97 was adopted with the introduction of NTSC color to minimize visual artifacts.

N

Adopted byArgentina,Paraguay, andUruguay (allPAL-N since 1980).

For historical reasons, some countries use a different video system onUHF than they do on theVHF bands. In a few countries, most notably theUnited Kingdom, television broadcasting on VHF has been entirely shut down. The British405-line system A, unlike all the other systems, suppressed the upper sideband rather than the lower—befitting its status as the oldest operating television system to survive into the color era (although was never officially broadcast with color encoding). System A was tested with all three color standards, and production equipment was designed and ready to be built; System A might have survived, as NTSC-A, had the British government not decided to harmonize with the rest of Europe on a 625-line video system, implemented in Britain as PAL-I on UHF only.

The French819 line system E was a post-war effort to advanceFrance's standing in television technology. Its 819 lines were almost high definition even by today's standards. Like the British system A, it was VHF only and remained black & white until its shutdown in 1984 in France and 1985 in Monaco. It was tested with SECAM standard in the early stages, but later the decision was made to adopt color in 625-lines L system only. Thus, France adopted system L both on UHF and VHF networks and abandoned system E.

Japan had the earliest working HDTV system (MUSE), with design efforts going back to 1979. The country began broadcasting wideband analoghigh-definition video signals in the late 1980s using an interlaced resolution of 1,125 lines, supported by theSony HDVS line of equipment.

In many parts of the world, analog television broadcasting has been shut down completely, or in process of shutdown; seeDigital television transition for a timeline of the analog shutdown.

Ignoring color, all television systems work in essentially the same manner. The monochrome image seen by a camera (later, theluminance component of a color image) is divided into horizontalscan lines, some number of which make up a single image orframe. A monochrome image is theoretically continuous, and thus unlimited in horizontal resolution, but to make television practical, a limit had to be placed on thebandwidth of the television signal, which puts an ultimate limit on the horizontal resolution possible. When color was introduced, this limit necessarily became fixed. All analog television systems areinterlaced: alternate rows of the frame are transmitted in sequence, followed by the remaining rows in their sequence. Each half of the frame is called avideo field, and the rate at which fields are transmitted is one of the fundamental parameters of a video system. It is related to theutility frequency at which theelectricity distribution system operates, to avoid flicker resulting from thebeat between the television screen deflection system and nearby mains generated magnetic fields. All digital, or "fixed pixel," displays haveprogressive scanning and mustdeinterlace an interlaced source. Use of inexpensive deinterlacing hardware is a typical difference between lower- vs. higher-pricedflat panel displays (Plasma display,LCD, etc.).

Allfilms and other filmed material shot at 24 frames per second must be transferred to videoframe rates using atelecine in order to prevent severe motion jitter effects. Typically, for 25 frame/s formats (European among other countries with 50 Hz mains supply), the content isPAL speedup, while a technique known as "3:2 pulldown" is used for 30 frame/s formats (North America among other countries with 60 Hz mains supply) to match the film frame rate to the video frame rate without speeding up the play back.

Analog television signal standards are designed to be displayed on acathode ray tube (CRT), and so the physics of these devices necessarily controls the format of the video signal. The image on a CRT is painted by a moving beam of electrons which hits aphosphor coating on the front of the tube. This electron beam is steered by a magnetic field generated by powerfulelectromagnets close to the source of the electron beam.

In order to reorient this magnetic steering mechanism, a certain amount of time is required due to theinductance of the magnets; the greater the change, the greater the time it takes for the electron beam to settle in the new spot.

For this reason, it is necessary to shut off the electron beam (corresponding to a video signal ofzero luminance) during the time it takes to reorient the beam from the end of one line to the beginning of the next (horizontal retrace) and from the bottom of the screen to the top (vertical retrace orvertical blanking interval). The horizontal retrace is accounted for in the time allotted to each scan line, but the vertical retrace is accounted for asphantom lines which are never displayed but which are included in the number of lines per frame defined for each video system. Since the electron beam must be turned off in any case, the result is gaps in the television signal, which can be used to transmit other information, such as test signals or color identification signals.

The temporal gaps translate into a comb-likefrequency spectrum for the signal, where the teeth are spaced at line frequency and concentrate most of the energy; the space between the teeth can be used to insert a color subcarrier.

Broadcasters later developed mechanisms to transmit digital information on the phantom lines, used mostly forteletext andclosed captioning:

• PALplus uses ahidden signaling scheme to indicate if it exists, and if so what operational mode it is in.
• NTSC was modified by theAdvanced Television Systems Committee to support ananti-ghosting signal that is inserted on a non-visible scan line.
• Teletext uses hidden signaling to transmit information pages.
• NTSCClosed Captioning signaling uses signaling that is nearly identical toteletext signaling.
• Widescreen signaling enables a flag to indicate that a 16:9 widescreen image is being broadcast, and allows the TV set to switch to the appropriate display mode.

Television images are unique in that they must incorporate regions of the picture with reasonable-quality content, that will never be seen by some viewers.^[vague]

In a purely analog system, field order is merely a matter of convention. For digitally recorded material it becomes necessary to rearrange the field order when conversion takes place from one standard to another.

Another parameter of analog television systems, minor by comparison, is the choice of whether vision modulation is positive or negative. Some of the earliest electronic television systems such as the British 405-line (System A) used positive modulation. It was also used in the two Belgian systems (System C, 625 lines, and System F, 819 lines) and the two French systems (System E, 819 lines, and System L, 625 lines). In positive modulation systems, as in the earlierwhite facsimile transmission standard, the maximum luminance value is represented by the maximum carrier power; in negativemodulation, the maximum luminance value is represented by zero carrier power. All newer analog video systems use negative modulation with the exception of the French System L.

Impulse noise, especially from older automotive ignition systems, caused white spots to appear on the screens of television receivers using positive modulation but they could use simple synchronization circuits. Impulse noise in negative-modulation systems appears as dark spots that are less visible, but picture synchronization was seriously degraded when using simple synchronization. The synchronization problem was overcome with the invention ofphase-locked synchronization circuits. When these first appeared in Britain in the early 1950s one name used to describe them was "flywheel synchronisation."

Older televisions for positive-modulation systems were sometimes equipped with a peak video signal inverter that would turn the white interference spots dark. This was usually user-adjustable with a control on the rear of the television labeled "White Spot Limiter" in Britain or "Antiparasite" in France. If adjusted incorrectly it would turn bright white picture content dark. Most of the positive modulation television systems ceased operation by the mid-1980s. The French System L continued on up to the transition to digital broadcasting. Positive modulation was one of several unique technical features that originally protected the French electronics and broadcasting industry from foreign competition and rendered French TV sets incapable of receiving broadcasts from neighboring countries.

Another advantage of negative modulation is that, since the synchronizing pulses represent maximum carrier power, it is relatively easy to arrange the receiverautomatic gain control to only operate during sync pulses and thus get a constant amplitude video signal to drive the rest of the TV set. This was not possible for many years with positive modulation as the peak carrier power varied depending on picture content. Modern digital processing circuits have achieved a similar effect but using the front porch of the video signal.

Given all of these parameters, the result is a mostly-continuousanalog signal which can be modulated onto a radio-frequency carrier and transmitted through an antenna. All analog television systems usevestigial sideband modulation, a form ofamplitude modulation in which one sideband is partially removed. This reduces the bandwidth of the transmitted signal, enabling narrower channels to be used.

In analog television, theanalog audio portion of a broadcast is invariably modulated separately from the video. Most commonly, the audio and video are combined at the transmitter before being presented to the antenna, but separate aural and visual antennas can be used. In all cases where negative video is used,FM is used for the standardmonaural audio; systems with positive video use AM sound and intercarrier receiver technology cannot be incorporated. Stereo, or more generally multi-channel, audio is encoded using a number of schemes which (except in the French systems) are independent of the video system. The principal systems areNICAM, which uses a digital audio encoding; double-FM (known under a variety of names, notablyZweikanalton, A2 Stereo, West German Stereo, German Stereo or IGR Stereo), in which case each audio channel is separately modulated in FM and added to the broadcast signal; and BTSC (also known asMTS), which multiplexes additional audio channels into the FM audio carrier. All three systems are compatible with monaural FM audio, but onlyNICAM may be used with the French AM audio systems.

The situation with worldwide digital television is much simpler by comparison. Most digital television systems are based on theMPEG transport stream standard, and use theH.262/MPEG-2 Part 2 videocodec. They differ significantly in the details of how the transport stream is converted into a broadcast signal, in the video format prior to encoding (or alternatively, after decoding), and in the audio format. This has not prevented the creation of an international standard that includes both major systems, even though they are incompatible in almost every respect.

The two principal digital broadcasting systems areATSC standards, developed by theAdvanced Television Systems Committee and adopted as a standard in most ofNorth America, andDVB-T, theDigitalVideoBroadcast –Terrestrial system used in most of the rest of the world.DVB-T was designed for format compatibility with existingdirect broadcast satellite services in Europe (which use theDVB-S standard, and also sees some use indirect-to-home satellite dish providers inNorth America), and there is also aDVB-C version for cable television. While the ATSC standard also includes support for satellite and cable television systems, operators of those systems have chosen other technologies (principally DVB-S or proprietary systems for satellite and256QAM replacing VSB for cable). Japan uses a third system, closely related to DVB-T, calledISDB-T, which is compatible withBrazil'sSBTVD. ThePeople's Republic of China has developed a fourth system, namedDMB-T/H.

The terrestrial ATSC system (unofficially ATSC-T) uses a proprietaryZenith-developed modulation called8-VSB; as the name implies, it is a vestigial sideband technique. Essentially, analog VSB is to regular amplitude modulation as 8VSB is to eight-wayquadrature amplitude modulation. This system was chosen specifically to provide for maximum spectral compatibility between existing analog TV and new digital stations in the United States' already-crowded television allocations system, although it is inferior to the other digital systems in dealing withmultipath interference; however, it is better at dealing withimpulse noise which is especially present on the VHF bands that other countries have discontinued from TV use, but are still used in the U.S. There is also nohierarchical modulation. After demodulation and error-correction, the 8-VSB modulation supports a digital data stream of about 19.39 Mbit/s, enough for one high-definition video stream or several standard-definition services. SeeDigital subchannel: Technical considerations for more information.

On November 17, 2017, the FCC voted 3-2 in favor of authorizing voluntary deployments ofATSC 3.0, which was designed as the successor to the original ATSC "1.0", and issued a Report and Order to that effect. Full-power stations will be required to maintain a simulcast of their channels on an ATSC 1.0-compatible signal if they decide to deploy an ATSC 3.0 service.^[9]

On cable, ATSC usually uses256QAM, although some use16VSB. Both of these double thethroughput to 38.78 Mbit/s within the same 6 MHzbandwidth. ATSC is also used over satellite. While these are logically called ATSC-C and ATSC-S, these terms were never officially defined.

DTMB is the digital television broadcasting standard of theMainland China,Hong Kong andMacau. This is a fusion system, which is a compromise of different competing proposing standards from different Chinese Universities, which incorporates elements fromDMB-T, ADTB-T and TiMi 3.

DVB-T usescoded orthogonal frequency division multiplexing (COFDM), which uses as many as 8000 independent carriers, each transmitting data at a comparatively low rate. This system was designed to provide superior immunity frommultipath interference, and has a choice of system variants which allow data rates from 4 MBit/s up to 24 MBit/s. One US broadcaster,Sinclair Broadcasting, petitioned theFederal Communications Commission to permit the use of COFDM instead of 8-VSB, on the theory that this would improve prospects for digital TV reception by households without outside antennas (a majority in the US), but this request was denied. (However, one US digital station, WNYE-DT inNew York, was temporarily converted to COFDM modulation on an emergency basis fordatacasting information to emergency services personnel in lowerManhattan in the aftermath of theSeptember 11 terrorist attacks).

DVB-S is the originalDigital Video Broadcasting forward error coding and modulation standard forsatellite television and dates back to 1995. It is used via satellites serving every continent of the world, includingNorth America. DVB-S is used in bothMCPC andSCPC modes forbroadcast networkfeeds, as well as fordirect broadcast satellite services likeSky andFreesat in the British Isles,Sky Deutschland andHD+ in Germany and Austria, TNT Sat/Fransat andCanalSat in France,Dish Network in the US, andBell Satellite TV in Canada. TheMPEG transport stream delivered by DVB-S is mandated as MPEG-2.

DVB-C stands forDigital Video Broadcasting - Cable and it is the DVB European consortium standard for the broadcast transmission ofdigital television overcable. This system transmits anMPEG-2 family digital audio/video stream, using aQAM modulation withchannel coding.

ISDB is very similar to DVB, however it is broken into 13 subchannels. Twelve are used for TV, while the last serves either as aguard band, or for the1seg (ISDB-H) service. Like the other DTV systems, the ISDB types differ mainly in the modulations used, due to the requirements of different frequency bands. The 12 GHz band ISDB-S uses PSK modulation, 2.6 GHz band digital sound broadcasting uses CDM and ISDB-T (in VHF and/or UHF band) uses COFDM with PSK/QAM. It was developed in Japan with MPEG-2, and is now used in Brazil with MPEG-4. Unlike other digital broadcast systems, ISDB includesdigital rights management to restrict recording of programming.

As interlaced systems require accurate positioning of scanning lines, it is important to make sure that the horizontal and vertical timebase are in a precise ratio. This is accomplished by passing the one through a series of electronic divider circuits to produce the other. Each division is by aprime number.

Therefore, there has to be a straightforward mathematical relationship between the line and field frequencies, the latter being derived by dividing down from the former. Technology constraints of the 1930s meant that this division process could only be done using small integers, preferably no greater than 7, for good stability. The number of lines was odd because of 2:1 interlace. The 405 line system used a vertical frequency of 50 Hz (Standard AC mains supply frequency in Britain) and a horizontal one of 10,125 Hz (50 ×405 ÷2)

• 2 × 3 × 3 × 5 gives90 lines (non interlaced)
• 2 × 2 × 2 × 2 × 2 × 3 gives96 lines (non interlaced)
• 2 × 2 × 3 × 3 × 5 gives180 lines (non interlaced) (used in Germany in mid-1930s before switch to 441-line system)
• 2 × 2 × 2 × 2 × 3 × 5 gives240 lines (used for the experimentalBaird transmissions in Britain[See Note 1])
• 3 × 3 × 3 × 3 × 3 gives243 lines
• 7 × 7 × 7 gives343 lines (early North American system also used in Poland and in Soviet Union before WW2)
• 3 × 5 × 5 × 5 gives375 lines
• 3 × 3 × 3 × 3 × 5 gives405 linesSystem A (used in Britain, Ireland and Hong Kong before 1985)
• 2 × 2 × 2 × 5 × 11 gives440 lines (non interlaced)
• 3 × 3 × 7 × 7 gives441 lines (used byRCA in North America before the 525-linesNTSC standard was adopted and widely used before WW2 in Continental Europe with different frame rates)
• 2 × 3 × 3 × 5 × 5 gives450 lines (non interlaced)
• 5 × 7 × 13 gives455 lines (used in France before WW2)
• 3 × 5 × 5 × 7 gives525 linesSystem M (480i) (a compromise between the RCA and Philco systems. Still used today in most of the Americas and parts of Asia)
• 3 × 3 × 3 × 3 × 7 gives567 lines (Developed byPhilips used for a while in the late 1940s in the Netherlands)
• 5 × 11 × 11 gives605 lines (proposed byPhilco in North America before the 525 standard was adopted)^{[citation needed]}
• 5 × 5 × 5 × 5 gives625 lines (576i) (designed by Soviet^{[10][11][12][13][14]} engineers during the mid-late 1940s, introduced to Western Europe by German engineers.)
• 2 × 3 × 5 × 5 × 5 gives750 lines at 50 frames (used for720p50)
• 2 × 3 × 5 × 5 × 5 gives 750 lines at 60 frames (used for720p60)
• 3 × 3 × 7 × 13 gives819 lines (737i) (used in France in the 1950s)
• 3 × 7 × 7 × 7 gives1,029 lines (proposed but never adopted around 1948 in France)
• 3 × 3 × 5 × 5 x 5 gives1,125 lines at 25 frames (used for1080i50 but not1080p25)
• 3 × 3 × 5 × 5 x 5 gives 1,125 lines at 30 frames (used for1080i60 but not1080p30)

Notes

1. The division of the 240-line system is academic as the scan ratio was determined entirely by the construction of the mechanical scanning system used with the cameras used with this transmission system.
2. The division ratio though relevant toCRT-based systems is largely academic today because modernLCD andplasma displays are not constrained to having the scanning in precise ratios. The 1080p high definition system requires 1125 lines in a CRT display.
3. The System I version of the 625-line standard originally used 582 active lines before later changing to 576 in line with other 625-line systems.

This sectiondoes notcite anysources. Please helpimprove this section byadding citations to reliable sources. Unsourced material may be challenged andremoved.(May 2023) (Learn how and when to remove this message)

Converting between different numbers of lines and different frequencies of fields/frames in video pictures is not an easy task. Perhaps the most technically challenging conversion to make is from any of the 625-line, 25-frame/s systems to system M, which has 525-lines at 29.97 frames per second. Historically this required a frame store to hold those parts of the picture not actually being output (since the scanning of any point was not time coincident). In more recent times, conversion of standards is a relatively easy task for a computer.

Aside from the line count being different, it's easy to see that generating 59.94 fields every second from a format that has only 50 fields might pose some interesting problems. Every second, an additional 10 fields must be generated seemingly from nothing. The conversion has to create new frames (from the existing input) in real time.

There are several methods used to do this, depending on the desired cost and conversion quality. The simplest possible converters simply drop every 5th line from every frame (when converting from 625 to 525) or duplicate every 4th line (when converting from 525 to 625), and then duplicate or drop some of those frames to make up the difference in frame rate. More complex systems include inter-field interpolation, adaptive interpolation, and phase correlation.

• Television antenna

Transmission technology standards

• Amateur television
• Broadcast safe
• Channel (broadcasting)
• Display resolution
• Lists of television channels for lists by country and language.
• Television channel frequencies
• Pan-American television frequencies
• European cable television frequencies
• Australian and New Zealand television frequencies

Defunct analog systems

• 405 lines
• 441 lines
• 819 lines
• MUSE ananalog high-definition television system.

Analog television systems

• Intercarrier method
• NTSC (525/60)
• PAL (color encoding usually used with 625/50 systems)
• PAL-M
• PAL-N
• PALplus
• SECAM
• Transposers
• TV transmitters

Analog television system audio

• Multichannel Television Sound
• NICAM (digital, analog pre-emphasis curve)
• Zweikanalton
• The defunct MUSE system had a very unusual digital audio subsystem completely unrelated toNICAM.

Digital television systems

• HDTV systems all useMPEG transport technology
• ATSC standards
• DVB-T andDVB-T2
• ISDB andISDB-T International (SBTVD)
• DTMB used in People's Republic of China, Hong Kong and Macau.

History

• History of television
• Oldest television station
• Television systems before 1940

• Characteristics of television systems.International Telecommunication Union, ITU-R Recommendation BT.470-2.[1]

• FARWAY IRFC, TV and Radio Transmission, Radio Data System Encoders, Broadcasting Technologies
• World Analog Television Standards and Waveforms by Alan Pemberton
• Analog TV Broadcast Systems by Paul Schlyter
• European Television Stations in 1932 a scan from a 1932 French magazine

• Broadcasting standards
• Television technology
• Television terminology
• Television transmission standards

• Webarchive template wayback links
• Articles with short description
• Short description is different from Wikidata
• Use dmy dates from January 2025
• All Wikipedia articles needing clarification
• Wikipedia articles needing clarification from September 2017
• All articles with unsourced statements
• Articles with unsourced statements from July 2024
• Articles needing additional references from May 2023
• All articles needing additional references