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Encyclopedia > Ultra high frequency
Ultra High Frequency (UHF)
Cycles per second: 300 MHz to 3 GHz

Wavelength: 1 m to 100 mm UHF may refer to: Ultra high frequency Ultra High Frequency (rock band), a New York rock band Unrestricted Hartree-Fock UHF (Independent UHF Broadcasting) Japanese television networks UHF (band), a Canadian folk music supergroup UHF (rock band), a Portuguese rock band UHF (film), a 1989 cult comedy film starring Weird...

Ultra high frequency (UHF) designates a range (band) of electromagnetic waves whose frequency is between 300 MHz and 3 GHz, which is 300 MHz to 3,000 MHz. Also known as the decimeter band or decimeter wave as the wavelengths range from ten to one decimeters. Radio waves whose frequency is above the UHF band fall into the SHF (Super high frequency) and EHF (Extremely high frequency) bands; all of which fall under the Microwave frequency range. Lower frequency signals fall into the VHF or lower bands. See electromagnetic spectrum for a full listing of frequency bands. A band is a small section of the spectrum of radio communication frequencies, in which channels are usually used or set aside for the same purpose. ... Electromagnetic radiation or EM radiation is a combination (cross product) of oscillating electric and magnetic fields perpendicular to each other, moving through space as a wave, effectively transporting energy and momentum. ... A wave is a disturbance that propagates through space or spacetime, transferring energy and momentum and sometimes angular momentum. ... For other uses, see Frequency (disambiguation). ... MegaHertz (MHz) is the name given to one million (106) Hertz, a measure of frequency. ... This article is about the SI unit of frequency. ... A decimetre (symbol: dm, American spelling: decimeter) is a measurement of distance equal to ten centimetres or 1/10 metre. ... Microwave Slang for small waves, like at a beach, often used by surfers. ... Extremely high frequency is the highest radio frequency band. ... This article is about the type of Electromagnetic radiation. ... Very high frequency (VHF) is the radio frequency range from 30 MHz to 300 MHz. ... Legend γ = Gamma rays HX = Hard X-rays SX = Soft X-Rays EUV = Extreme ultraviolet NUV = Near ultraviolet Visible light NIR = Near infrared MIR = Moderate infrared FIR = Far infrared Radio waves EHF = Extremely high frequency (Microwaves) SHF = Super high frequency (Microwaves) UHF = Ultra high frequency VHF = Very high frequency HF = High...

Contents

Uses

UHF and VHF are the most commonly used frequency bands for transmission of television signals. Modern mobile phones also transmit and receive within the UHF spectrum. UHF is widely used by public service agencies for two-way radio communication, usually using narrowband frequency modulation, but digital services are on the rise. There has traditionally been very little radio broadcasting in this band until recently; see digital audio broadcasting for details. The Global Positioning System also uses UHF. In communications, transmission is the act of transmitting electrical messages (and the associated phenonomena of radiant energy that pass through media). ... In telecommunications, frequency modulation (FM) conveys information over a carrier wave by varying its frequency. ... Digital Audio Broadcasting (DAB), also known as Eureka 147, is a technology for broadcasting of audio using digital radio transmission. ... Over fifty GPS satellites such as this NAVSTAR have been launched since 1978. ...


One uncommon use of UHF waves is for the detection of partial discharges. Partial discharges occur due to the sharp geometries created in high voltage insulated equipment. The advantage of UHF detection is that this method can be used to localize the source of the discharge. A drawback to UHF detection is the extreme sensitivity to external noise. UHF detection methods are used in the field, especially for large distribution transformers. In electrical engineering, a partial discharge (PD) is a localised dielectric breakdown of a small portion of a solid or liquid electrical insulation system under high voltage stress. ... Look up Discharge in Wiktionary, the free dictionary. ... International safety symbol Caution, risk of electric shock (ISO 3864), colloquially known as high voltage symbol. ... Figure 1:Three-phase pole-mounted step-down transformer. ...


2.45 GHz, now mainly used for microwave ovens, has been proposed for Wireless energy transfer. Some pilot experiments have been performed, but it is not used on a large scale. It has been suggested that this article be split into articles entitled Microwave oven and Microwave heating. ... It has been suggested that Power beaming be merged into this article or section. ...


Amateur radio operators also operate in several UHF bands. An amateur radio operator An amateur radio operator is an individual who has been assigned an amateur radio license by a governmental regulatory authority. ...


Characteristics and advantages

Main article: radio propagation

The point to point transmission of radio waves is affected by many variables. Atmospheric moisture, the stream of particles from the sun called solar wind, and time of day will all have an effect on the signal transmission. All radio waves are partially absorbed by atmospheric moisture. Atmospheric absorption reduces, or attenuates, the strength of radio signals over long distances. The effects of attenuation increases according to the frequency. UHF signals are generally more degraded by moisture than lower bands such as VHF. The layer of the Earth's atmosphere called the ionosphere is filled with charged particles that can reflect radio waves. The reflection of radio waves can be helpful in transmitting a radio signal over long distances as the wave repeatedly bounces from the sky to the ground. UHF benefits less from the effects of reflection than lower (VHF, etc.) frequencies. UHF transmissions may be enhanced by tropospheric ducting as the atmosphere warms and cools throughout the day. Radio propagation is a term used to explain how radio waves behave when they are transmitted, or are propagated from one point on the Earth to another. ... The plasma in the solar wind meeting the heliopause The solar wind is a stream of charged particles (i. ... Attenuation is the decrease in intensity of electromagnetic radiation due to absorption or scattering of photons. ... Relationship of the atmosphere and ionosphere The ionosphere is the uppermost part of the atmosphere, distinguished because it is ionized by solar radiation. ... Tropospheric ducting (also known as tropospheric refraction) is a type of radio propagation that tends to happen during periods of stable, anti-cyclonic weather. ...


The main advantage of UHF transmission is the physically short wave that is produced by the high frequency. The size of transmission and reception equipment, (particularly antennas), is related to the size of the radio wave. Smaller and less conspicuous antennas can be used with higher frequency bands. In biology, antenna (plural: antennae) refers to the sensing organs of several arthropods. ...


UHF is widely used in two-way radio systems and cordless telephones. UHF signals travel over line-of-sight distances. Transmissions generated by two-way radios and cordless telephones do not travel far enough to interfere with local transmissions. A number of public safety and business communications are handled on UHF. Civilian applications such as GMRS, PMR446, UHF CB, and 802.11b ("WiFi") are popular uses of UHF frequencies. A repeater is used to propagate UHF signals when a distance that is greater than the line-of-sight is required. A modern GE cordless telephone, model 26930 A cordless telephone or portable telephone is a telephone with a wireless handset which communicates via radio waves with a base station connected to a fixed telephone line (POTS) and can only be operated near (typically less than 100 meters) its base station... The General Mobile Radio Service (GMRS) is a land-mobile radio service in the United States available for short-distance two-way communications to facilitate the activities of an adult individual and his or her immediate family members, including a spouse, children, parents, grandparents, aunts, uncles, nephews, nieces, and in... Alan 456r PMR446 (Personal Mobile Radio, 446 MHz) is a radio frequency part of the UHF range that is open without licensing for personal usage in most members of the European Union. ... UHF CB is a licence-free citizens band radio service authorised by the government of Australia in the UHF 477MHz band. ... IEEE 802. ... A repeater is an electronic device that receives a weak or low-level signal and retransmits it at a higher level or higher power, so that the signal can cover longer distances without degradation. ...


History

United States

On December 29, 1949, KC2XAK of Bridgeport, Connecticut, became the first UHF television station to operate on a regular daily schedule. The first commercially licensed UHF television station on the air was KPTV/Channel 27 (now VHF Channel 12) in Portland, Oregon, on September 18, 1952. The station even used much of the equipment, including the transmitter, from KC2XAK, which was delivered by high-speed freight train. is the 363rd day of the year (364th in leap years) in the Gregorian calendar. ... Year 1949 (MCMXLIX) was a common year starting on Saturday (link will display the full calendar) of the Gregorian calendar. ... KC2XAK was the worlds first UHF television station. ... “Bridgeport” redirects here. ... KPTV is the Fox television affiliate serving the Portland, Oregon metropolitan area. ... Nickname: Location of Portland in Multnomah County and the state of Oregon Coordinates: , Country State County Multnomah County Incorporated February 8, 1851 Government  - Mayor Tom Potter[1]  - Commissioners Sam Adams Randy Leonard Dan Saltzman Erik Sten  - Auditor Gary Blackmer Area  - City 376. ... is the 261st day of the year (262nd in leap years) in the Gregorian calendar. ... Year 1952 (MCMLII) was a leap year starting on Tuesday (link will display full calendar) of the Gregorian calendar. ...


Hopes that UHF would allow dozens of television stations in every media market were thwarted by poor image frequency rejection in superheterodyne tuners with 45.75 MHz Intermediate frequency. This shortcoming led to "UHF taboos" which limited each area to only modestly more UHF than VHF stations, despite the much larger number of channels. See [1] A media market, broadcast market, media region, designated market area, DMA or simply market is a region where the population can receive the same (or similar) television and radio station offerings, and may also include other types of media including newspapers and Internet content. ... Image frequency: In radio reception using heterodyning in the tuning process, an undesired input frequency that is capable of producing the same intermediate frequency (IF) that the desired input frequency produces. ... The Super Heterodyne receiver (or to give it its full name, The Supersonic Heterodyne Receiver) was invented by Edwin Armstrong in 1918. ... An intermediate frequency (IF) is a frequency to which a carrier frequency is shifted as an intermediate step in transmission or reception. ...


In the United States, UHF stations (broadcast channels above 13) originally gained a reputation for being locally owned, less polished and professional, not as popular, and having weaker signal propagation than their VHF counterparts (channels 2 through 13). The movie UHF, starring "Weird Al" Yankovic and Michael Richards (of Seinfeld fame), parodied the phenomenon. In the late 1940s/early 1950s, affiliates of the four major US television networks (NBC, CBS, ABC and DuMont) transmitted their programs primarily through VHF. Most UHF stations that operated in major population centers of the USA were unable to obtain network affiliation, thus were independent stations. ABC and Dumont, being later and (at that time) less prosperous networks, did have a number of UHF affiliates, and the later PBS had even more. Conversely, many mid-sized and small television markets within the United States were too close to the outer fringe of the broadcast range of VHF stations from major population centers to qualify for their own VHF license from the FCC, because of interference from would-be overlapping broadcast ranges. Instead, the FCC granted many mid-sized and small-sized cities only UHF licenses (even for the big three networks), because the broadcast range of UHF is shorter, so fewer overlaps would occur between the mid-size market's UHF stations and the rather far-away big-city UHF stations. UHF was rereleased on DVD in 2002 by MGM UHF (also known as The Vidiot from UHF) is a comedy cult film made in 1989. ... This article is about the musician himself. ... For other persons named Michael Richards, see Michael Richards (disambiguation). ... Seinfeld can refer to: Seinfeld - a popular TV series that ran 1989-1998. ... A television network is a distribution network for television content whereby a central operation provides programming for many television stations. ... This article is about the television network. ... This article is about the broadcast network. ... The American Broadcasting Company (ABC) operates television and radio networks in the United States and is also shown on basic cable in Canada. ... The DuMont Television Network was the worlds first commercial television network, beginning operation in the United States in 1946. ... “PBS” redirects here. ... The FCCs official seal. ...


A minority of UHF TV transmitters have no programming or commercial identity of their own, and merely retransmit the signal of a VHF station that owns it, to a smaller area poorly covered by the VHF signal. Such transmitters are called "translators" rather than “stations”. In broadcasting, a translator is an FM radio station or a TV station which acts as a full-duplex repeater. ...


The distinction between UHF and VHF characteristics has declined in importance with the emergence of additional broadcast television networks (Fox, The CW, The Tube, MyNetworkTV, and ION), and the decline of direct OTA reception. The concentration of media ownership, the proliferation of cable television, digital television and DBS have contributed to the quality equalization of VHF and UHF broadcasts. Most HDTV stations broadcast over-the-air signals using UHF bands. The Fox Broadcasting Company is a television network in the United States. ... “The CW” redirects here. ... The Tube Music Network is a music video network carried on select digital television subchannels and digital cable systems. ... MyNetworkTV (sometimes written My Network TV, and unofficially abbreviated MyNet, MyTV, MNT, or MNTV) is a television network in the United States, owned by News Corporation. ... ION Television is a broadcast and cable television network first broadcast on August 31, 1998 under the name PAX TV (early on in its development, it was called PaxNet). ... Terrestrial television (also known as over-the-air, OTA or broadcast television) was the traditional method of television broadcast signal delivery prior to the advent of cable and satellite television. ... Concentration of media ownership (also known as media consolidation) is a commonly used term among media critics, policy makers, and others to characterize ownership structure of mass media industries. ... Coaxial cable is often used to transmit cable television into the house. ... Digital television (DTV) is a telecommunication system for broadcasting and receiving moving pictures and sound by means of digital signals, in contrast to analog signals used by analog (traditional) TV. DTV uses digital modulation data, which is digitally compressed and requires decoding by a specially designed television set, or a... Direct broadcast satellite (DBS) is a term used to refer to satellite television broadcasts intended for home reception, also referred to as direct-to-home signals. ... Projection screen in a home theater, displaying a high-definition television image. ...


The Family Radio Service and General Mobile Radio Service use the 462 and 467 MHz areas of the UHF spectrum. There is a considerable amount of (legal) unlicensed activity (cordless phones, wireless networking) clustered around 900 MHz and 2.4 GHz frequencies. The Family Radio Service is an improved walkie talkie system authorized in the United States. ... GMRS capable handheld radio The General Mobile Radio Service (GMRS) is a land-mobile UHF radio service in the United States available for short-distance two-way communications to facilitate the activities of an adult individual who possesses a valid GMRS license, as well his or her immediate family members...


United Kingdom

In Britain, UHF television began with the launch of BBC2 in 1964. BBC1 and ITV soon added their own services on UHF (British channels 21 to 69) on November 15, 1969, and PAL colour was introduced on UHF only in 1967 (for BBC2) & 1969 (for BBC1 & ITV). VHF only carried BBC1 & ITV and was only ever in 405 line Black & White (though early on, there were plans to add colour to the existing 405-line services). VHF television was closed in January 1985. Today all British terrestrial (non-satellite) television channels (analogue and digital) are on UHF. A drawback to this is the very large number of small relay transmitters needed to fill in gaps in the main transmitters' coverage, which would not have been necessary with a VHF system due to its different propagation characteristics. This article does not cite any references or sources. ... Also Nintendo emulator: 1964 (emulator). ... BBC One is the primary television channel of the BBC, and the first in the United Kingdom. ... Independent Television (generally known as ITV, but also as ITV Network) is a public service network of British commercial television broadcasters, set up under the Independent Television Authority (ITA) to provide competition to the BBC. ITV is the oldest commercial television network in the UK. Since 1990 and the Broadcasting... is the 319th day of the year (320th in leap years) in the Gregorian calendar. ... Also: 1969 (Stargate SG-1) episode. ... For other uses, see PAL (disambiguation). ... Year 1967 (MCMLXVII) was a common year starting on Sunday (link will display full calendar) of the 1967 Gregorian calendar. ... Also: 1969 (Stargate SG-1) episode. ... This article is about the year. ... Analog television encodes television picture information as an analog signal, that is, by varying the voltages and/or frequencies of the signal. ... Digital television (DTV) uses digital modulation and compression to broadcast video, audio and data signals to television sets. ...


Australia

In Australia, UHF was first anticipated in the mid 1970s with channels 28 to 69. The first UHF TV broadcasts in Australia were operated by Special Broadcasting Service (SBS) on channel 28 in Sydney and Melbourne starting in 1980, and translator stations for the Australian Broadcasting Corporation (ABC). The UHF band is now used extensively as ABC, SBS, commercial and community (public access) television services have expanded particularly through regional areas. The 1970s decade refers to the years from 1970 to 1979, also called The Seventies. ... The Special Broadcasting Service (SBS) is one of two government funded Australian public broadcasting radio and television networks, the other being the Australian Broadcasting Corporation (ABC). ... This article is about the metropolitan area in Australia. ... This article is about the Australian city; the name may also refer to City of Melbourne or Melbourne city centre. ... The Australian Broadcasting Corporation or ABC is Australias national non-profit public broadcaster. ... The Australian Broadcasting Corporation or ABC is Australias national non-profit public broadcaster. ... Public access television is a cable television service that allows members of the public to use a cable companys facilities and equipment to create and broadcast their own content. ...


Australia also provides the UHF CB service for general-purpose two-way communications. UHF CB is a licence-free citizens band radio service authorised by the government of Australia in the UHF 477MHz band. ...


Ireland

In the Republic of Ireland, UHF was introduced in 1978 to augment the existing RTÉ One VHF 625-line transmissions and to provide extra frequencies for the new RTÉ Two channel. The first UHF transmitter site was Cairn Hill in Co. Longford, followed by Three Rock Mountain in South Co. Dublin. These sites were followed by Clermont Carn in Co. Louth and Holywell Hill in Co. Donegal in 1981. Elsewhere in Ireland, both the RTÉ channels are available on VHF. Since then RTÉ have migrated nearly all their low-power relay sites to UHF. TV3 and TG4 are transmitted entirely in UHF only. When Digital Terrestrial TV is introduced, it is intended to broadcast this on UHF only. VHF TV is likely to cease whenever the existing analogue broadcasts are switched off. The UHF band is also used in parts of Ireland for Television deflector systems bringing British television signals to towns and rural areas which cannot receive these signals directly RTÉ One (Irish: RTÉ a hAon) is the Republic of Irelands oldest and most popular television channel, operated by Irish state broadcaster Radio Telefís Éireann. ... RTÉ Two (Irish: RTÉ a Dó) (known from 1988 to 2004 as Network 2, RTÉ Network Two, RTÉ2 or N2) is Irelands second-oldest television channel, operated by Irish state broadcaster Radio Telefís Éireann. ... A number of mountains in the British Isles have the name Cairn Hill Cairn Hill, Northumberland in Northumberland, England Carn Clonhugh in County Longford, Ireland which is also known as Cairn Hill Category: ... Statistics Province: Leinster County Town: Longford Code: LD Area: 1,091 km² Population (2006) 34,361 Website: www. ... Three Rock Mountain is a mountain in the Wicklow Mountains in the south east of Ireland. ... Dublin (Irish Áth Cliath) is the area that contains the City of Dublin, the capital and largest city of the Republic of Ireland; and the counties of Dun Laoghaire-Rathdown, Fingal and South Dublin. ... This article belongs in one or more categories. ... County Louth (Contae Lú in Irish) is a county on the east coast of Ireland. ... Statistics Province: Ulster County Town: Lifford Code: DL Area: 4,841 km² Population (2006) 146,956 Website: www. ... The deployment of digital terrestrial television in Ireland has had a chequered history, with the first tests being carried out in 1998, but no public trials until August 2006. ... Analog television encodes television picture information as an analog signal, that is, by varying the voltages and/or frequencies of the signal. ...


Malaysia

UHF broadcasting was used outside Kuala Lumpur and the Klang Valley by private TV station TV3 in the late 80s, with the government stations only transmitting in VHF (Bands 1 and 3) and the 450 MHz range being occupied by the ATUR cellular phone service operated by Telekom Malaysia. The ATUR service ceased operation in the late 90s, freeing up the frequency for other uses. UHF was not commonly used in the Klang Valley until 1994 (despite TV3's signal also being available over UHF Channel 29, as TV3 transmitted over VHF Channel 12 in the Klang Valley). 1994 saw the introduction of the channel MetroVision (which ceased transmission in 1999, got bought over by TV3's parent company - System Televisyen Malaysia Berhad - and relaunched as 8TV in 2004). This was followed by Ntv7 in 1998 (also acquired by TV3's parent company in 2005) and recently Channel 9 (which started in 2003, ceased transmission in 2005, was also acquired by TV3's parent company shortly after, and came back as TV9 in early 2006). At current count, there are 4 distinct UHF signals receivable by an analog TV set in the Klang Valley: Channel 25 (8TV), Channel 29 (TV3 UHF transmission), Channel 37 (NTV7) and Channel 39 (TV9). Channel 35 is usually allocated for VCRs, decoder units (i.e. the ASTRO and MiTV set top boxes) and other devices that have an RF signal generator (i.e. game consoles). Nickname: Motto: Maju dan makmur (English: Progress and Prosper) Location in Malaysia Coordinates: , Country State Establishment 1857 Granted city status 1974 Government  - Mayor (Datuk Bandar) Datuk Abdul Hakim Borhan From 14 December 2006 Area  - City 243. ... Klang Valley is the area in central Selangor, Malaysia comprising Kuala Lumpur and its surroundings and suburbs naturally delineated by hilly areas and the Port Klang coastline. ... Sistem Televisyen Malaysia Berhad (STMB) or TV3 was incorporated in 1983 as Malaysia’s first commercial television station. ... Telekom Malaysia Berhad (TM) is the largest telecommunication company in Malaysia. ... 8TV (Simplified Chinese: ; Pinyin: Bā Dù Kōng Jiān) is a private Malaysian television station previously known as Metrovision. ... Natseven TV Sdn Bhd or better known as ntv7 is the first digital terrestrial television in Malaysia was launched nationwide on April 7, 1998. ... TV9 is a Malaysian private-owned television station which started transmission on April 22, 2006. ... The term set-top box (STB) describes a device that connects to a television and some external source of signal, and turns the signal into content then displayed on the screen. ...


Frequency allocation

United States

A brief summary of some UHF frequency usage:

  • 300–420 MHz: government use, including meteorology and Military/Federal two-way use.
  • 420–450 MHz: Government radiolocation and Amateur radio (ham - 70 cm band).
  • 450–470 MHz: UHF business band, General Mobile Radio Service, and Family Radio Service 2-way "walkie-talkies", Public Safety Use.
  • 470–512 MHz: TV channels 14–20, public safety
  • 512–698 MHz: TV channels 21–51 (channel 37 used for radio astronomy)
  • 698–806 MHz: TV channels 52–69 (to be auctioned for other uses once conversion to digital TV has been accomplished)
  • 806–824 MHz: pocket pagers and Nextel SMR band (formerly TV channels 70–72)
  • 824–849 MHz: Cellular phones, A & B franchises, mobile phone (formerly TV channels 73–77)
  • 849–869 MHz: public safety 2-way (fire, police, ambulance - formerly TV channels 77–80)
  • 869–894 MHz: cellular phones, A & B franchises, base station (formerly TV channels 80–83)
  • 902–928 MHz: ISM band: cordless phones and stereo, Radio Frequency Identification, datalinks, Amateur radio (33 cm band)
  • 928–960 MHz: mixed Studio-Transmitter Links, mobile 2-way, 929/931MHz Paging, other.
  • 1240–1300 MHz: Amateur radio (ham - 23 cm band)
  • 1850–1910 MHz: PCS mobile phone—note below
  • 1920–1930 MHz: DECT Cordless telephone
  • 1930–1990 MHz: PCS base stations—note below
  • note: order is A, D, B, E, F, C blocks. A, B, C = 15 MHz; D, E, F = 5 MHz
  • 2310–2360 MHz: Satellite radio (Sirius and XM)
  • 2390–2450 MHz: Amateur radio (ham - 13 cm band)
  • 2400–2483.5 MHz: ISM, IEEE 802.11, 802.11b, 802.11g Wireless LAN, IEEE 802.15.4
  • around 2450 MHz: Microwave oven

// Meteorology (from Greek: μετέωρον, meteoron, high in the sky; and λόγος, logos, knowledge) is the interdisciplinary scientific study of the atmosphere that focuses on weather processes and forecasting. ... Amateur radio station with modern solid-state transceiver featuring LCD display and DSP capabilities Amateur radio, often called ham radio, is a hobby that uses various types of radio broadcasting equipment to communicate with other radio amateurs for public service, recreation and self-training. ... 70 Centimeters is a common ham radio band in the UHF spectrum. ... GMRS capable handheld radio The General Mobile Radio Service (GMRS) is a land-mobile UHF radio service in the United States available for short-distance two-way communications to facilitate the activities of an adult individual who possesses a valid GMRS license, as well his or her immediate family members... The Family Radio Service is an improved walkie talkie system authorized in the United States. ... The Very Large Array, a radio interferometer in New Mexico, USA Radio astronomy is a subfield of astronomy that studies celestial objects in the radio frequency portion of the electromagnetic spectrum. ... Digital television (DTV) is a telecommunication system for broadcasting and receiving moving pictures and sound by means of digital signals, in contrast to analog signals used by analog (traditional) TV. DTV uses digital modulation data, which is digitally compressed and requires decoding by a specially designed television set, or a... “Cell Phone” redirects here. ... The industrial, scientific and medical (ISM) radio bands were originally reserved internationally for non-commercial use of RF electromagnetic fields for industrial, scientific and medical purposes. ... An EPC RFID tag used for Wal-Mart Radio Frequency Identification (RFID) is an automatic identification method, relying on storing and remotely retrieving data using devices called RFID tags or transponders. ... 33 Centimeters is an amateur radio band. ... See http://en. ... A modern GE cordless telephone, model 26930 A cordless telephone or portable telephone is a telephone with a wireless handset which communicates via radio waves with a base station connected to a fixed telephone line (POTS) and can only be operated near (typically less than 100 meters) its base station... // A satellite radio or subscription radio (SR) is a digital radio signal that is broadcast by a communications satellite, which covers a much wider geographical range than terrestrial radio signals. ... Sirius Satellite Radio NASDAQ: SIRI is one of two satellite radio (SDARS) services operating in the United States and Canada, along with XM Satellite Radio. ... “XM” redirects here. ... Ism can be Interstellar medium A suffix -ism. ... IEEE 802. ... Lan can stand for several things: A local area network Lan (airline) formerly LanChile Lan Peru Län, a kind of administrative division used in Sweden Lan Mandragoran, a fictional character in the Wheel of Time fantasy series by Robert Jordan. ... ZigBee is a proprietary set of high level communication protocols designed to use small, low power digital radios based on the IEEE 802. ... It has been suggested that this article be split into articles entitled Microwave oven and Microwave heating. ...

United Kingdom

  • 380–395 MHz: Terrestrial Trunked Radio (TETRA) service for emergency use
  • 430–440 MHz: Amateur radio (ham - 70 cm band)
  • 606–614 MHz: Protected for radio-astronomy
  • 470–862 MHz: TV channels 21–69 (channel 36 used for radar, channel 38 used for radio astronomy, channel 69 used for licenced and licence exempt wireless microphones, channels 31-40 and 63-68 to be released and may be made available for other uses by Ofcom. Public consultation due December 2006)
  • 1240–1316 MHz: Amateur radio (ham - 23 cm band)
  • 1880–1900 MHz: DECT Cordless telephone
  • 2310–2450 MHz: Amateur radio (ham - 13 cm band)

The TETRA logo TErrestrial Trunked RAdio (TETRA) (formerly known as Trans European Trunked RAdio) is a specialist Professional Mobile Radio and walkie talkie standard used by police departments, fire departments, ambulance services and the military. ... 70 Centimeters is a common ham radio band in the UHF spectrum. ... See http://en. ... A modern GE cordless telephone, model 26930 A cordless telephone or portable telephone is a telephone with a wireless handset which communicates via radio waves with a base station connected to a fixed telephone line (POTS) and can only be operated near (typically less than 100 meters) its base station...

Australia

  • UHF Citizens Band: 476.425 - 477.400 MHz Refer: http://www.manilla2007.com/Default.aspx?tabid=145

See also

Radio spectrum
ELF SLF ULF VLF LF MF HF VHF UHF SHF EHF
3 Hz 30 Hz 300 Hz 3 kHz 30 kHz 300 kHz 3 MHz 30 MHz 300 MHz 3 GHz 30 GHz
30 Hz 300 Hz 3 kHz 30 kHz 300 kHz 3 MHz 30 MHz 300 MHz 3 GHz 30 GHz 300 GHz


In the United States and Canada, TV channel 37 occupies a band of frequencies from 608 to 614 MHz. ... The following tables show the frequencies assigned to broadcast television channels in various regions of the world, along with the ITU letter designator for the system used. ... Radio frequency, or RF, refers to that portion of the electromagnetic spectrum in which electromagnetic waves can be generated by alternating current fed to an antenna. ... Extremely low frequency (ELF) is the band of radio frequencies from 3 to 30 Hz. ... Super Low Frequency (SLF) is the frequency range between 30 hertz and 300 hertz. ... Ultra Low Frequency (ULF) is the frequency range between 300 hertz and 3000 hertz. ... Very low frequency or VLF refers to radio frequencies (RF) in the range of 3 to 30 kHz. ... Low Frequency or LF refers to Radio Frequencies (RF) in the range of 30–300 kHz. ... Mediumwave radio transmissions (sometimes called Medium frequency or MF) are those between the frequencies of 300 kHz and 3000 kHz. ... High frequency (HF) radio frequencies are between 3 and 30 MHz. ... Very high frequency (VHF) is the radio frequency range from 30 MHz (wavelength 10 m) to 300 MHz (wavelength 1 m). ... Microwave Slang for small waves, like at a beach, often used by surfers. ... Extremely high frequency is the highest radio frequency band. ...

External links

  • Tomislav Stimac, "Definition of frequency bands (VLF, ELF... etc.)". IK1QFK Home Page (vlf.it).

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