View source for Very high frequency

{{Short description|Electromagnetic wave range of 30–300 MHz}}
{{redirect|VHF|the diseases|Viral hemorrhagic fever}}
[[File:Antenna.jpg|thumb|VHF [[television antenna]]s used for [[broadcast television]] reception.  These six antennas are a type known as a [[Yagi-Uda antenna|Yagi antenna]], which is widely used on VHF.]]
{{MWband
| freq = 30 [[megahertz|MHz]] to 300 [[megahertz|MHz]]
| wave = 10 to 1 m
| bands = 
}}

'''Very high frequency''' ('''VHF''') is the [[International Telecommunication Union|ITU]] designation<ref name="Belov">{{cite book
  | last1 = Belov
  | first1 = Leonid A.
  | last2  = Smolskiy
  | first2 = Sergey M.
  | last3  = Kochemasov
  | first3 = Viktor Neofidovich
  | title = Handbook of RF, Microwave, and Millimeter-wave Components
  | publisher = Artech House
  | date = 2012
  | location = 
  | pages = 27
  | language = 
  | url = https://books.google.com/books?id=bHhYjINB6KMC&pg=PA27
  | archive-url= 
  | archive-date=
  | doi = 
  | id = 
  | isbn = 9781608072095
  | mr = 
  | zbl = 
  | jfm =}}</ref><ref name="1037B">{{cite book
  | title = US Federal Standard 1037B: Telecommunications, Glossary of Telecommunications Terms 
  | publisher = Office of Technology Standards, General Services Administration
  | series = 
  | volume = 
  | edition = 
  | date = 3 June 1991
  | location = 
  | pages = S-18
  | language = 
  | url = https://books.google.com/books?id=zYLXU4fkD34C&pg=RA15-PA18
  | archive-url= 
  | archive-date=
  | doi = 
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  | zbl = 
  | jfm =}}</ref><ref name="itu-2015-acts">{{cite conference |date=2015 |title=Final Acts WRC-15 |url=https://www.itu.int/dms_pub/itu-r/opb/act/R-ACT-WRC.12-2015-PDF-E.pdf |conference=World Radiocommunication Conference |location=Geneva, Switzerland |publisher=International Telecommunications Union |pages = 4|access-date=2025-01-12}}</ref> for the range of [[radio frequency]] [[electromagnetic wave]]s ([[radio wave]]s) from 30 to 300 [[megahertz]] (MHz), with corresponding wavelengths of ten meters to one meter. 
Frequencies immediately below VHF are denoted [[high frequency]] (HF), and the next higher frequencies are known as [[ultra high frequency]] (UHF).

VHF radio waves propagate mainly by [[line-of-sight propagation|line-of-sight]], so they are blocked by hills and mountains, although due to refraction they can travel somewhat beyond the [[horizon|visual horizon]] out to about 160&nbsp;km (100 miles).  Common uses for radio waves in the VHF band are [[Digital Audio Broadcasting]] (DAB) and [[FM radio]] broadcasting, [[Terrestrial television|television broadcasting]], [[two-way radio|two-way]] [[land mobile radio system]]s (emergency, business, private use and military), long range [[data communication]] up to several tens of kilometers with [[radio modem]]s, [[amateur radio]], and [[marine VHF radio|marine communications]]. [[Air traffic control]] communications and air navigation systems (e.g. [[VHF omnidirectional range|VOR]] and [[Instrument landing system|ILS]]) work at distances of {{convert|100|km|miles}}  or more to aircraft at cruising altitude.

In the Americas and many other parts of the world, VHF [[Band I]] was used for the transmission of [[analog television]]. As part of the worldwide [[digital television transition|transition to digital terrestrial television]] most countries require broadcasters to air television in the VHF range using digital, rather than analog encoding.

==Propagation characteristics==
Radio waves in the VHF band propagate mainly by [[line-of-sight propagation|line-of-sight]] and ground-bounce paths; unlike in the [[high frequency|HF]] band there is only some reflection at lower frequencies from the [[ionosphere]] ([[skywave]] propagation).<ref name="Seybold">{{cite book | last1  = Seybold | first1 = John S.  | title  = Introduction to RF Propagation | publisher = John Wiley and Sons | date   = 2005 | pages  = 9–10 | url    = https://books.google.com/books?id=4LtmjGNwOPIC&q=VHF&pg=PA9 | isbn   = 978-0471743682 }}</ref>  They do not follow the contour of the Earth as [[ground wave]]s and so are blocked by hills and mountains, although because they are weakly refracted (bent) by the atmosphere they can travel somewhat beyond the [[horizon|visual horizon]] out to about 160&nbsp;km (100 miles). They can penetrate building walls and be received indoors, although in urban areas reflections from buildings cause [[multipath propagation]], which can interfere with television reception.  Atmospheric [[radio noise]] and interference ([[radio frequency interference|RFI]]) from electrical equipment is less of a problem in this and higher frequency bands than at lower frequencies.  The VHF band is the first band at which efficient transmitting antennas are small enough that they can be mounted on vehicles and portable devices, so the band is used for [[two way radio|two-way]] [[land mobile radio system]]s, such as [[walkie-talkie]]s, and [[two way radio]] communication with aircraft ([[Airband]]) and ships ([[marine radio]]).  Occasionally, when conditions are right, VHF waves can travel long distances by [[tropospheric ducting]] due to refraction by temperature gradients in the atmosphere.

==Line-of-sight calculation==
[[File:Rabbit-ears dipole antenna with UHF loop 20090204.jpg|thumb|"Rabbit-ears" VHF [[television antenna]] (the small loop is a separate UHF antenna)]]

VHF transmission range is a function of transmitter power, receiver sensitivity, and distance to the horizon, since VHF signals propagate under normal conditions as a near [[Line-of-sight propagation|line-of-sight]] phenomenon. The distance to the [[radio horizon]] is slightly extended over the geometric line of sight to the horizon, as radio waves are weakly bent back toward the Earth by the atmosphere.

An approximation to calculate the line-of-sight horizon distance (on Earth) is:
*distance in nautical miles = <math>1.23\times\sqrt{  A_\textrm{ft}}</math> where <math>A_\textrm{ft}</math> is the height of the antenna in feet<ref>{{Cite web |last=Senesac |first=David |title=Visual Line of Sight Calculations dependent on Earth's Curvature |url=https://www.davidsenesac.com/Information/line_of_sight.html#:~:text=The%20distance%20to%20the%20horizon,by%2012%20equals%201%20mile.}}</ref>
*distance in kilometers = <math>\sqrt{12.746 \times A_\textrm{m}}</math> where <math>A_\textrm{m}</math> is the height of the antenna in meters.<ref>{{Cite web |title=Distance to the Horizon |url=https://aty.sdsu.edu/explain/atmos_refr/horizon.html }}</ref>

These approximations are only valid for antennas at heights that are small compared to the radius of the Earth. They may not necessarily be accurate in mountainous areas, since the landscape may not be transparent enough for radio waves.

In engineered communications systems, more complex calculations are required to assess the probable coverage area of a proposed transmitter station.<ref>{{Cite web |title=Radio Wave Propagation Theory |url=https://imdpune.gov.in/training/communication/LN_11_60_Radio%20Wave%20Propagation%20Theory.pdf}}</ref>

==Antennas==
{{see also|UHF television broadcasting#UHF vs VHF}}
[[File:Superturnstile Tx Muehlacker.JPG|thumb|A VHF television broadcasting antenna. This is a common type called a super turnstile or [[batwing antenna]]. ]]

VHF is the first band at which wavelengths are small enough that efficient transmitting antennas are short enough to mount on vehicles and handheld devices, a [[whip antenna|quarter wave whip antenna]] at VHF frequencies is 25&nbsp;cm to 2.5 meter (10 inches to 8 feet) long. So the VHF and UHF wavelengths are used for [[two-way radio]]s in vehicles, aircraft, and handheld [[transceiver]]s and [[walkie-talkie]]s. Portable radios usually use [[whip antenna|whips]] or [[rubber ducky antenna]]s, while base stations usually use larger fiberglass whips or [[collinear antenna array|collinear arrays]] of vertical dipoles.

For directional antennas, the [[Yagi-Uda antenna|Yagi antenna]] is the most widely used as a [[high gain antenna|high gain]] or "beam" antenna. For television reception, the Yagi is used, as well as the [[log-periodic antenna]] due to its wider bandwidth. [[Helical antenna|Helical]] and [[turnstile antenna]]s are used for [[satellite communication]] since they employ [[circular polarization]]. For even higher gain, multiple Yagis or helicals can be mounted together to make [[array antennas]]. Vertical [[collinear antenna array|collinear arrays]] of dipoles can be used to make high gain [[omnidirectional antenna]]s, in which more of the antenna's power is radiated in horizontal directions. Television and FM broadcasting stations use collinear arrays of specialized dipole antennas such as [[batwing antenna]]s.

==Universal use==
Certain subparts of the VHF band have the same use around the world. Some national uses are detailed below.
*50&ndash;54&nbsp;MHz: [[amateur radio]] [[6-meter band]].
*108&ndash;118&nbsp;MHz: Air navigation beacons [[VHF omnidirectional range|VOR]] and [[Instrument Landing System]] localizer.
*118&ndash;137&nbsp;MHz: [[Airband]] for [[air traffic control]], [[Amplitude modulation|AM]], 121.5&nbsp;MHz is emergency frequency
*144&ndash;146&nbsp;MHz: [[amateur radio]] [[2-meter band]] (Extends up to 148&nbsp;MHz in some Regions).
*156&ndash;174&nbsp;MHz: VHF maritime mobile band for [[VHF maritime radio|maritime two-way radio]] on ships.

==By country==
[[File:VHF Usage.svg|thumb|700px|center|A plan showing VHF use in [[terrestrial television|television]], [[FM radio]], [[amateur radio]], [[marine radio]] and [[airband|aviation]].]]

===Australia===
{{see also|Australasian television frequencies}}
The VHF TV band in Australia was originally allocated channels 1 to 10-with channels&nbsp;2, 7 and 9 assigned for the initial services in [[Sydney]] and [[Melbourne]], and later the same channels were assigned in [[Brisbane]], [[Adelaide]] and [[Perth]]. Other capital cities and regional areas used a combination of these and other frequencies as available. The initial commercial services in [[Hobart]] and [[Darwin, Northern Territory|Darwin]] were respectively allocated channels&nbsp;6 and 8 rather than 7 or 9.

By the early 1960s it became apparent that the 10&nbsp;VHF channels were insufficient to support the growth of television services. This was rectified by the addition of three additional frequencies-channels 0, 5A and 11. Older television sets using rotary dial tuners required adjustment to receive these new channels. Most TVs of that era were not equipped to receive these broadcasts, and so were modified at the owners' expense to be able to tune into these bands; otherwise the owner had to buy a new TV.

Several TV stations were allocated to VHF channels&nbsp;3, 4 and 5, which were within the FM radio bands although not yet used for that purpose. A couple of notable examples were [[NBN Television|NBN-3]] [[Newcastle, New South Wales|Newcastle]], [[WIN (TV station)|WIN-4]] [[Wollongong]] and [[Australian Broadcasting Corporation|ABC]] [[Newcastle, New South Wales|Newcastle]] on channel&nbsp;5. While some Channel&nbsp;5 stations were moved to 5A in the 1970s and 80s, beginning in the 1990s, the [[Australian Broadcasting Authority]] began a process to move these stations to [[Ultra high frequency|UHF]] bands to free up valuable VHF spectrum for its original purpose of FM radio. In addition, by 1985 the federal government decided new TV stations are to be broadcast on the UHF band.

Two new VHF channels, 9A and 12, have since been made available and are being used primarily for digital services (e.g. [[Australian Broadcasting Corporation|ABC]] in capital cities) but also for some new analogue services in regional areas. Because channel&nbsp;9A is not used for television services in or near Sydney, Melbourne, Brisbane, Adelaide or Perth, [[Digital radio in Australia|digital radio]] in those cities are broadcast on DAB frequencies blocks 9A, 9B and 9C.

VHF radio is also used for marine Radio<ref>{{cite web |url=https://www.acma.gov.au/theacma/marine-vhf-radio |title=Marine VHF radio |publisher=[[Australian Communications & Media Authority|]]}}</ref> as per its long-distance reachability comparing UHF frequencies.

Example allocation of VHF–UHF frequencies:<ref>{{cite web |url=https://www.acma.gov.au/theacma/australian-radiofrequency-spectrum-plan-spectrum-planning-acma |title=Australian radiofrequency spectrum plan |series=Planning |publisher=Australian Communications & Media Authority}}</ref> 
* Radionavigation&nbsp;60: 84&ndash;86&nbsp;MHz
* Fixed Maritime Mobile: 130&ndash;135.7&nbsp;MHz
* Fixed Aeronautical radio navigation: 160&ndash;190&nbsp;MHz
* Broadcasting Aeronautical Radionavigation:  255&ndash;283.5&nbsp;MHz
* Aeronautical Radionavigation AUS&nbsp;49 / Maritime Radionavigation (radiobeacons)&nbsp;73: 315&ndash;325&nbsp;MHz

===New Zealand===
*44&ndash;51, 54&ndash;68&nbsp;MHz: [[Band I]] Television (channels 1&ndash;3)
*87.5&ndash;108&nbsp;MHz: [[Band II]] Radio
*118&ndash;137&nbsp;MHz: [[Airband]] for [[air traffic control]], [[Amplitude modulation|AM]]
**108&ndash;117.975&nbsp;MHz: Air navigation beacons [[VHF omnidirectional range|VOR]] and [[Instrument landing system|ILS]]
**121.5&nbsp;MHz is an emergency frequency
*144&ndash;148&nbsp;MHz: [[Amateur radio]] [[2-meter band]]
*156&ndash;162.2&nbsp;MHz: [[Marine VHF radio|Marine radio]] 
*174&ndash;230&nbsp;MHz: [[Band III]] Television (channels 4&ndash;11)

Until 2013, the four main free-to-air TV stations in [[New Zealand]] used the VHF television bands ([[Band I]] and [[Band III]]) to transmit to New Zealand households. Other stations, including a variety of pay and regional free-to-air stations, were forced to broadcast in the [[Ultra high frequency|UHF]] band, since the VHF band had been very overloaded with four stations sharing a very small frequency band, which was so overcrowded that one or more channels would not be available in some smaller towns.

However, [[Digital changeover dates in New Zealand|at the end of 2013]], all television channels stopped broadcasting on the VHF bands, as New Zealand moved to digital television broadcasting, requiring all stations to either broadcast on UHF or satellite (where UHF was unavailable) utilising the [[Freeview (New Zealand)|Freeview]] service.<ref>{{cite web|title=Going Digital - When is my area going digital?|url=http://www.goingdigital.co.nz/making-the-switch/coverage-areas-2/coverage-areas.html|work=goingdigital.co.nz|publisher=Ministry for Culture and Heritage|access-date=20 October 2011|url-status=dead|archive-url=https://web.archive.org/web/20111017073751/http://www.goingdigital.co.nz/making-the-switch/coverage-areas-2/coverage-areas.html|archive-date=17 October 2011}}</ref>

Refer to [[Australasian television frequencies]] for more information.

===United Kingdom===
{{unreferenced section|date=August 2016}}

British television originally used VHF [[band I]] and [[band III]]. Television on VHF was in black and white with [[405-line]] format (although there were experiments with all three colour systems-[[NTSC]], [[PAL]], and [[SECAM]]-adapted for the 405-line system in the late 1950s and early 1960s).

British colour television was broadcast on [[Ultra high frequency|UHF]] (channels 21–69), beginning in the late 1960s. From then on, TV was broadcast on both VHF and UHF (VHF being a monochromatic downconversion from the 625-line colour signal), with the exception of [[BBC Two|BBC2]] (which had always broadcast solely on UHF). The last British VHF TV transmitters closed down on January 3, 1985. VHF [[band III]] is now used in the UK for [[digital audio broadcasting]], and VHF [[band II]] is used for [[FM radio]], as it is in most of the world.

Unusually, the UK has an [[amateur radio]] allocation at [[4 metres]], 70–70.5&nbsp;MHz.

===United States and Canada===
Frequency assignments between US and Canadian users are closely coordinated since much of the Canadian population is within VHF radio range of the US border. Certain discrete frequencies are reserved for [[radio astronomy]].
The general services in the VHF band are:

*30&ndash;49.6&nbsp;MHz: Licensed 2-way land mobile communication, with various sub-bands.<ref group=lower-alpha>The 42&nbsp;MHz Segment is still in current use by the [[California Highway Patrol]], [[New Jersey State Police]], Tennessee Highway Patrol, and other state law enforcement agencies.</ref>
*30&ndash;88&nbsp;MHz: Military VHF [[frequency modulation|FM]], including [[SINCGARS]]
*43&ndash;50&nbsp;MHz: [[Cordless telephone]]s, 49&nbsp;MHz FM walkie-talkies and radio controlled toys, and mixed 2-way mobile communication. The FM broadcast band originally operated here (42&ndash;50&nbsp;MHz) before it was moved to 88&ndash;108&nbsp;MHz.
*50&ndash;54&nbsp;MHz: [[Amateur radio]] [[6-meter band]]
**50.8&ndash;51&nbsp;MHz: [[Radio-controlled aircraft]] (on ten fixed frequencies at 20&nbsp;kHz spacing) with an [[Amateur radio licensing in the United States|FCC amateur radio Service license]], flown under FCC Part 97, rule 97.215.<ref>{{Cite web |url=https://www.ecfr.gov/cgi-bin/text-idx?c=ecfr&SID=336ab7469b61ecbfa15086dbf1bf2c59&rgn=div5&view=text&node=47:5.0.1.1.6&idno=47#se47.5.97_1215 |title=Electronic Code of Federal Regulations (ECFR) |access-date=2019-03-05 |archive-date=2021-01-26 |archive-url=https://web.archive.org/web/20210126140226/https://www.ecfr.gov/cgi-bin/text-idx?c=ecfr&rgn=div5&view=text&node=47:5.0.1.1.6&idno=47#se47.5.97_1215 |url-status=dead }}</ref> 
*54&ndash;88&nbsp;MHz, known as "[[Band I|Band&nbsp;I]]" internationally; some DTV stations will appear here. See [[Pan-American television frequencies]].
**54&ndash;72&nbsp;MHz [[television|TV]] channels&nbsp;2&ndash;4 (VHF-Lo)
**72&ndash;76&nbsp;MHz: Radio controlled models, industrial remote control, and other devices. [[Radio-controlled aircraft|Model aircraft]] operate on 72&nbsp;MHz while surface models operate on 75&nbsp;MHz in the US and Canada, air navigation beacons 74.8&ndash;75.2&nbsp;MHz.
**76&ndash;88&nbsp;MHz TV channels&nbsp;5&ndash;6 (VHF-Lo)
*87.5&ndash;108&nbsp;MHz: [[FM radio]] broadcasting (87.9&ndash;91.9 non-commercial, 92&ndash;108 commercial in the United States) (known as "[[Band II|Band&nbsp;II]]" internationally)
*108&ndash;118&nbsp;MHz: Air navigation beacons [[VHF omnidirectional range|VOR]]
*118&ndash;137&nbsp;MHz: [[Airband]] for [[air traffic control]], [[Amplitude modulation|AM]]
**121.5&nbsp;MHz is an emergency frequency
*137&ndash;138&nbsp;MHz Space research, space operations, meteorological satellite<ref name=CanadianTable>{{cite book |publisher=Industry Canada |title=Canadian Table of Frequency Allocations 9&nbsp;kHz &ndash; 275&nbsp;GHz |edition=2005 (revised February 2007) |date=February 2007 |pages=29–30}}</ref>
*138&ndash;144&nbsp;MHz: Land mobile, auxiliary civil services, satellite, space research, and other miscellaneous services
*144&ndash;148&nbsp;MHz: [[Amateur radio]] [[2-meter band]]
*148&ndash;150&nbsp;MHz: Land mobile, fixed, satellite
*150&ndash;156&nbsp;MHz: "VHF [[business band]]", public safety, the unlicensed [[Multi-Use Radio Service]] (MURS), and other 2-way land mobile, FM
*156&ndash;158&nbsp;MHz [[Marine VHF radio|VHF Marine Radio]]
**156.8&nbsp;MHz (Channel 16) is the maritime emergency and contact frequency.
* 159.81-161.565&nbsp;MHz railways<ref group=lower-alpha>The 160 and 161&nbsp;areas are Association of American Railroads (AAR) 91&ndash;channel [[railroad]] radios, issued to the railroad. For example, AAR&nbsp;21 is 160.425&nbsp;MHz and that is issued to [[Tennessee Valley Railroad Museum]], as well as other railroads that want AAR Channel&nbsp;21.</ref> 
**159.81&ndash;160.2 are railroads in Canada only and are used by trucking companies in the U.S.
*160.6&ndash;162 Wireless microphones and TV/FM broadcast remote pickup
*162.4&ndash;162.55: [[Weather radio|NOAA Weather Stations]], narrowband FM, Weatheradio Canada Stations
*174&ndash;240&nbsp;MHz, known as "[[Band III|Band&nbsp;III]]" internationally. A number of DTV channels have begun broadcasting here, especially many of the stations which were assigned to these channels for previous analog operation.
**174&ndash;216&nbsp;MHz television channels&nbsp;7&ndash;13 (VHF-Hi)
**174&ndash;216&nbsp;MHz: professional wireless microphones (low power, certain exact frequencies only)
**216&ndash;222&nbsp;MHz: land mobile, fixed, maritime mobile,<ref name=CanadianTable/>
**222&ndash;225&nbsp;MHz: [[1.25-meter band|1.25&nbsp;meters]] (US) (Canada 219&ndash;220, 222&ndash;225&nbsp;MHz) [[amateur radio]]
*225&nbsp;MHz and above (UHF): Military aircraft radio, 243&nbsp;MHz is an emergency frequency (225&ndash;400&nbsp;MHz) AM, including [[HAVE QUICK]], dGPS RTCM-104

[[Cable television]], though not transmitted aerially, uses a spectrum of frequencies overlapping VHF.<ref>{{cite web |url=http://www.jneuhaus.com/fccindex/cablech.html |title=Cable TV Channel Frequencies |website=www.jneuhaus.com |access-date=27 April 2018 |url-status=live |archive-url=https://web.archive.org/web/20170823053431/http://www.jneuhaus.com/fccindex/cablech.html |archive-date=23 August 2017 |df=dmy-all}}</ref>

====VHF television====
The U.S. [[Federal Communications Commission|FCC]] allocated television broadcasting to a channelized roster as early as 1938 with 19&nbsp;channels. That changed three more times: in 1940 when Channel&nbsp;19 was deleted and several channels changed frequencies, then in 1946 with television going from 18&nbsp;channels to 13&nbsp;channels, again with different frequencies, and finally in 1948 with the removal of [[Channel 1 (North American TV)|Channel&nbsp;1]] (analog channels&nbsp;2–13 remain as they were, even on [[cable television]]).<ref>{{cite web |url=http://www.tech-notes.tv/History&Trivia/Channel%20One/Channel_1.htm |series=Tech Notes |title=What Ever Happened to Channel&nbsp;1? |at=Table&nbsp;1 <!-- Retrieved March 27, 2014 --> |website=tech-notes.tv |access-date=27 April 2018 |url-status=live |archive-url=https://web.archive.org/web/20170317040906/http://www.tech-notes.tv/History%26Trivia/Channel%20One/Channel_1.htm |archive-date=17 March 2017 |df=dmy-all}}</ref> Channels 14–19 later appeared on the UHF band, while channel 1 remains unused.

====87.5&ndash;87.9 MHz====
87.5&ndash;87.9&nbsp;MHz is a radio band which, in most of the world, is used for [[FM broadcasting]]. In [[North America]], however, this bandwidth is allocated to VHF television channel&nbsp;6 (82&ndash;88&nbsp;MHz). The analog audio for TV channel&nbsp;6 is broadcast at 87.75&nbsp;MHz (adjustable down to 87.74). Several stations, known as [[Channel 6 radio stations in the United States|Frankenstation]]s, most notably those joining the [[Pulse 87]] franchise, have operated on this frequency as radio stations, though they use television licenses. As a result, FM radio receivers such as those found in automobiles which are designed to tune into this frequency range could receive the audio for analog-mode programming on the local TV channel 6 while in North America. The practice largely ended with the [[Digital television transition in the United States|DTV transition]] in 2009, although some still exist.

The FM broadcast channel at 87.9&nbsp;MHz is normally off-limits for FM audio broadcasting; it is reserved for displaced class&nbsp;D stations which have no other frequencies in the normal 88.1&ndash;107.9&nbsp;MHz subband to move to. So far, only two stations have qualified to operate on 87.9&nbsp;MHz: 10&ndash;watt [[KSFH]] in [[Mountain View, California]] and 34&ndash;watt translator [[K200AA]] in [[Sun Valley, Nevada]].

==Unlicensed operation==
In some countries, particularly the United States and Canada, limited low-power license-free operation is available in the FM broadcast band for purposes such as [[micro-broadcasting]] and sending output from [[Compact disc|CD]] or digital media players to radios without auxiliary-in jacks, though this is illegal in some other countries. This practice was legalised in the United Kingdom on 8 December 2006.<ref>{{cite web|url=http://media.ofcom.org.uk/2006/11/23/change-to-the-law-to-allow-the-use-of-low-power-fm-transmitters-for-mp3-players/|title=Change to the law to allow the use of low power FM transmitters for MP3 players|date=23 November 2006|publisher=Ofcom|archive-url=https://web.archive.org/web/20110807165012/http://media.ofcom.org.uk/2006/11/23/change-to-the-law-to-allow-the-use-of-low-power-fm-transmitters-for-mp3-players/|archive-date=7 August 2011|url-status=dead|access-date=2 October 2012}}</ref>

==See also==
*[[TV radio]]
*[[List of oldest radio stations]]
*[[Apex (radio band)]]
*[[FM broadcast band]]
*[[Polar mesosphere summer echoes]]
*[[Television channel frequencies]]
*[[Knife-edge effect]]
*[[VHF omnidirectional range]]

==Notes==
{{notelist}}

==References==
{{reflist}}

{{commons category}}
{{TVRband}}
{{Radio_spectrum}}
{{EMSpectrum}}
{{Telecommunications}}
{{Analogue TV transmitter topics}}
{{Audio broadcasting}}
{{Authority control}}

[[Category:Radio spectrum]]
[[Category:Television terminology]]