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Encyclopedia > FM broadcast band

In most of the world, the FM broadcast band, used for broadcasting FM radio stations, goes from 87.5 to 108.0 MHz. In the Americas (ITU region 2) it starts at 87.8, at the top end of TV channel 6. In Japan the FM broadcast band is 76–90 MHz, unlike any other country in the world. The old OIRT band in Eastern Europe was 65.8–74 MHz. Shortcut: WP:CU Marking articles for cleanup This page is undergoing a transition to an easier-to-maintain format. ... This Manual of Style has the simple purpose of making things easy to read by following a consistent format — it is a style guide. ... Wikibooks has more about this subject: Marketing Note: broadcasting is also a term for hand sowing. ... The abbreviations FM, Fm, and fm may refer to: Electrical engineering Frequency modulation (FM) and its most common applications: FM broadcasting, used primarily to broadcast music and speech at VHF frequencies FM synthesis, a sound-generation technique popularized by early digital synthesizers Science Femtometre (fm), an SI measure of length... To meet Wikipedias quality standards and appeal to a wider international audience, this article may require cleanup. ... MegaHertz (MHz) is the name given to one million (106) Hertz, a measure of frequency. ... World map showing the Americas The Americas consists of the land in the Western hemisphere. ... This article is about the location. ... Braun HF 1, Germany, 1958 OT-1471 Belweder, Poland, 1957 Television is a telecommunication system for broadcasting and receiving moving pictures and sound over a distance. ... The International Radio and Television Organisation (official name in French: Organisation Internationale de Radiodiffusion et de Télévision or OIRT), more often called Intervision (Russian Интервидение, Polish Interwizja), was an East European network of radio and television broadcasters... Regions of Europe as delineated by the United Nations (UN definition of Eastern Europe marked salmon):  Northern Europe  Western Europe  Eastern Europe  Southern Europe Pre-1989 division between the West (grey) and Eastern Bloc (orange) superimposed on current national boundaries: Russia (dark orange), other countries of the former USSR (medium...


The name "FM band" is misleading, since one can transmit FM on any frequency within the VHF range. All of these bands mentioned are in the VHF band which extends from 30 MHz to 300 MHz. In some countries FM broadcast radio is referred to as "VHF", "UKW" (German "Ultrakurzwelle" — "Ultra Short Wave") or "УКВ" (Russian "Ультра Короткие Волны"). The abbreviations FM, Fm, and fm may refer to: Electrical engineering Frequency modulation (FM) and its most common applications: FM broadcasting, used primarily to broadcast music and speech at VHF frequencies FM synthesis, a sound-generation technique popularized by early digital synthesizers Science Femtometre (fm), an SI measure of length... Very high frequency (VHF) is the radio frequency range from 30 MHz (wavelength 10 m) to 300 MHz (wavelength 1 m). ...

Contents

CCIR bandplan

Center frequencies

While most countries use frequencies ending in .1, .3, .5, .7, or .9, some use .0, .2, .4, .6, and .8. Still others use .15, .35, .55, .75, .95, or .05, .25, .45, .65, .85 instead.


An ITU Geneva conference of 1984-12-07 resolved to discontinue the use of 50 kHz offsets throughout Eastern and Western Europe [1]. 1984 (MCMLXXXIV) was a leap year starting on Sunday of the Gregorian calendar. ... December 7 is the 341st day (342nd in leap years) of the year in the Gregorian calendar. ...

  • Most nations have used 100 kHz or 200 kHz offsets for FM broadcasting since the 1984 ITU Geneva conference.
  • Some FM digital tuners may not be able to tune in 50 kHz increments; these receivers should not be used by the international traveller.

Some countries, such as Italy which has a heavily-congested FM band, still allow a station on any 50 kHz boundary where it can be squeezed in.

Interference of two circular waves - Wavelength (decreasing bottom to top) and Wave centers distance (increasing to the right). ... The abbreviations FM, Fm, and fm may refer to: Electrical engineering Frequency modulation (FM) and its most common applications: FM broadcasting, used primarily to broadcast music and speech at VHF frequencies FM synthesis, a sound-generation technique popularized by early digital synthesizers Science Femtometre (fm), an SI measure of length... In telecommunication, a capture effect is a phenomenon, associated with FM reception, in which only the stronger of two signals at or near the same frequency will be demodulated. ... In radio terminology, a receiver is an electronic circuit that receives a radio signal from an antenna and decodes the signal for use as sound, pictures, navigational-position information, etc. ... The word selectivity has more meanings: Selectivity, the ability to notice/distinguish small differences. ...

ITU Region II Bandplan and Channel Numbering

The original bandplan in North America actually used 42-50 MHz but this was changed in 1945. Currently in Canada and the United States, each channel is numbered from 200 (87.9 MHz) to 300 (107.9 MHz) in increments of 1 (200 kHz). 87.9 MHz, while technically part of TV channel 6 (82.0–88.0 MHz), is used by two class-D stations in the U.S.. Portable radio tuners often tune down to 87.5, so the same equipment can be marketed worldwide. Automobiles are unlikely to go overseas, but usually tune down to 87.7, so that TV channel 6 audio on 87.75 MHz can be received (although at a somewhat lower volume). In most of the world, the FM broadcast band, used for broadcasting FM radio stations, goes from 87. ... This is the list of broadcast station classes. ... Motto: (Out Of Many, One) (traditional) In God We Trust (1956 to date) Anthem: The Star-Spangled Banner Capital Washington D.C. Largest city New York City None at federal level (English de facto) Government Federal constitutional republic  - President George Walker Bush (R)  - Vice President Dick Cheney (R) Independence from... Portable communications devices refer to hand-held or wearable devices. ... A Sansui TU-X1 stereo FM tuner. ... For the magazine called automobile, see Automobile Magazine. ...


In the United States, the center frequencies of 87.9 though to 91.9 are reserved for non-commercial stations only, e.g., religious or educational. The center frequencies 92.1 through to 107.9 may contain either commercial or non-commercial stations. (Neither Canada nor Mexico observe this reservation.)


Originally, the FCC devised a bandplan where stations would be assigned at intervals of 4 channels, or 800 kHz separation, for any one geographic area. Thus, in mid-Missouri, stations might be at 88.1, 88.9, 89.7, etc., while in the St. Louis area, stations might be at 88.3, 89.1, 89.9, 90.7, etc. Certain frequencies were designated for Class A only (see FM broadcasting), which had a limit of 3 kW ERP and an antenna height limit for the center of radiation of 300 feet height above average terrain (HAAT). These frequencies were: 92.1, 92.7, 93.5, 94.3, 95.3, 95.9, 96.7, 97.7, 98.3, 99.3, 100.1, 100.9, 101.7, 102.3, 103.1, 103.9, 104.9, 105.5, 106.3, and 107.1. On other frequencies, stations could be Class B (50 kW, 500 feet) or Class C (100 kW, 2000 feet), depending on which Zone they were in. FM broadcasting is a broadcast technology invented by Edwin Howard Armstrong that uses frequency modulation (FM) to provide high-fidelity sound over broadcast radio. ... In radio telecommunications, effective radiated power or ERP is determined by subtracting system losses from system gains. ... HAAT is used extensively in radio, as it is actually much more important than power. ...


In the late 1980s, the FCC switched to a "bandplan" based on a distance separation table using currently operating stations, and subdivided the class table to create extra classes and change antenna height limits to meters. Class A power was doubled to 6 kW, and the frequency restrictions noted above were removed. Basically, as of late 2004, a station can be "squeezed in" anywhere as long as the location and class conforms to the rules in separation table. The rules for second-adjacent-channel spacing do not apply for stations licensed prior to 1964.


The basic formulae determining radio channels for North America as mentioned are as follows:

  • ({color{Red}mathrm{MHz}} - 47.9) * 5 = {color{Blue}mathrm{channel number}}
  • {{color{Blue}mathrm{channel number}} over 5} + 47.9 = {color{Red}mathrm{MHz}}

Deviation and bandpass

Normally, each channel is 200 kHz (0.2 MHz) wide, and can pass audio and subcarrier frequencies up to 100 kHz. Deviation is up to 200 kHz total, or ±100 kHz, but is typically limited to 150 kHz total (±75 kHz) in order to prevent interference to adjacent channels on the band. Stations in the U.S. may go up to 10% over this if they use stereo or other subcarriers, increasing total modulation by 1% for each 2% used by the subcarriers. Channel, in communications (sometimes called communications channel), refers to the medium used to convey information from a sender (or transmitter) to a receiver. ... The hertz (symbol: Hz) is the SI unit of frequency. ... Wikibooks has more about this subject: Marketing Note: broadcasting is also a term for hand sowing. ... A subcarrier is separate analog or digital signal carried on a main radio transmission, which carries extra information such as voice or data. ... In radio, frequency deviation is the result of frequency modulation. ... In broadcasting an adjacent channel is an AM, FM, or TV channel that is next to another channel. ... A subcarrier is separate analog or digital signal carried on a main radio transmission, which carries extra information such as voice or data. ... In telecommunications, modulation is the process of varying a periodic waveform, i. ...


OIRT bandplan

The OIRT FM broadcast band covers 65.8 to 74 MHz. It was used in the Union of Soviet Socialist Republics and most of the other socialist countries of Eastern Europe, with the exception of East Germany and Yugoslavia, which always used the 87.5 to 108 MHz broadcast band in line with Western Europe. The International Radio and Television Organisation (official name in French: Organisation Internationale de Radiodiffusion et de Télévision or OIRT), more often called Intervision (Russian Интервидение, Polish Interwizja), was an East European network of radio and television broadcasters... Soviet redirects here. ... Socialism is a social and economic system (or the political philosophy advocating such a system) in which the economic means of production are owned and controlled collectively by the people. ... Regions of Europe as delineated by the United Nations (UN definition of Eastern Europe marked salmon):  Northern Europe  Western Europe  Eastern Europe  Southern Europe Pre-1989 division between the West (grey) and Eastern Bloc (orange) superimposed on current national boundaries: Russia (dark orange), other countries of the former USSR (medium... GDR redirects here. ... Yugoslavia (Jugoslavija in Latin, Југославија in Cyrillic, English: Land of the South Slavs) describes four political entities that existed one at a time on the Balkan Peninsula in Europe, during most of the 20th century. ...


Following the collapse of the communist governments in Eastern Europe, the 87.5 to 108 MHz band began to be adopted and is now in use in all countries. This was prompted by the expansion of broadcasting and the modernisation of existing transmission networks, using new or second-hand transmitters from western countries, together with a general desire for standardisation with the West.


Many countries have completely ceased broadcasting on the OIRT FM band, although declining use continues in others, mainly the former republics of the USSR. The future of broadcasting on the OIRT FM band is limited, due to the lack of new consumer receivers for that band.


Countries which still use the OIRT band include Russia[2], Belarus[3], Moldova[4] and Hungary[5]. However, Hungary plans to close down its remaining transmitters in 2006. 2006 (MMVI) was a common year starting on Sunday of the Gregorian calendar. ...


Unlike Western practice, OIRT FM frequencies are based on 10 kHz rather than 50 or 100 kHz multiples. This may have been to reduce co-channel interference caused by Sporadic E propagation and other atmospheric effects, which occur more often at these frequencies. Sporadic E propagation is a relatively rare form of propagation where a radio wave bounces off a sporadic E cloud, notated as Es in the E layer region of the ionosphere. ...


The 4 meters amateur radio allocation used in many European countries is entirely within the OIRT FM band. Operators on this band and the 6 metre (50 MHz) band use the presence of broadcast stations as an indication that there is an "opening" into Eastern Europe or Russia. This can be a mixed blessing because the 4 metre amateur allocation is only 0.5 MHz or less, and a single broadcast station causes considerable interference to a large part of the band. // Summary 4 metres is an Amateur Radio frequency band in the lower Very High Frequency spectrum. ... Ham radio station with modern solid-state transceiver featuring LCD display and DSP capabilities Ham radio station with vintage vacuum tube gear featuring separate transmitter, receiver and power supply Amateur radio, often called Ham radio, is a hobby and public service enjoyed by about 6 million people throughout the world. ...


It will be noted that the System D television channels R4 and R5 lie wholly or partly within the 87.5-108 MHz FM audio broadcast band. Countries which still use System D therefore have to consider the re-organisation of TV broadcasting in order to make full use of this band for audio broadcasting. 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. ...


Japanese bandplan

The FM band in Japan is 76-90 MHz. The 90-108 MHz section is used for TV audio for VHF Channels 1,2 and 3. The narrowness of the Japanese band (14 MHz compared to slightly more than 20 MHz for the CCIR band) limits the number of FM stations that can be accommodated on the dial with the result that many commercial radio stations are forced to use AM.


Many Japanese radios are designed to be capable of receiving both the Japanese FM band and the CCIR FM band, so that the same model can be sold within Japan or exported. The radio may cover 76 to 108 MHz, the frequency coverage may be selectable by the user, or during assembly the radio may be set to operate on one band by means of a specially-placed diode or other internal component.


Conventional analog-tuned (dial & pointer) radios may be marked with "TV Sound" in the 90-108 section. If these radios were sold in the USA, for example, the 76-88 section would be marked TV sound for VHF channels 2, 3, 4, 5 and 6, with the 88-108 section band as normal FM.


Second-hand automobiles imported from Japan contain a radio designed for the Japanese FM band, and importers often fit a "converter" to down-convert the 87.5 to 107.9 MHz band to the frequencies that the radio can accept. In addition to showing an incorrect frequency, there are two other disadvantages that can result in poor reception; the converter "compresses" the frequencies making the stations appear closer together, and the original antenna may perform poorly on the higher FM band. Also, RDS is not used in Japan, whereas most modern car radios available in Europe make use of this system. A better solution is to replace the radio and antenna with ones designed for the country where the car will be used. Radio Data System, or RDS, is a standard from the European Broadcasting Union for sending small amounts of digital information using conventional FM radio broadcasts. ...


Historic US bandplan

Early FM broadcasting in North America originally used the 42-50MHz band (this range was also used by a class of experimental wideband AM starions known as "apex broadcasters") shortly after WW2 the FCC decided to move FM broadcasters to the 88.1-105.9 (later 87.9-107.9) MHz band.


See also


  Results from FactBites:
 
FM broadcast band - Wikipedia, the free encyclopedia (1082 words)
This was prompted by the expansion of broadcasting and the modernisation of existing transmission networks, using new or second-hand transmitters from western countries, together with a general desire for standardisation with the West.
The future of broadcasting on the OIRT FM band is limited, due to the lack of new consumer receivers for that band.
Operators on this band and the 6 metre (50 MHz) band use the presence of broadcast stations as an indication that there is an "opening" into Eastern Europe or Russia.
FM broadcast radio - definition of FM broadcast radio in Encyclopedia (1448 words)
FM radio, and later stereo FM radio, were both developed in the United States primarily by Edwin Armstrong.
FM radio was assigned the 42 to 50 MHz band of the spectrum in 1940.
FM audio for television channel 6 is broadcast at a carrier frequency of 87.75 MHz, and many radios can tune down this low; a few low-power television stations licensed for channel 6 are operated solely for their right to use this frequency and broadcast only nominal video programming.
  More results at FactBites »

 
 

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