FM broadcasting.docx

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FM broadcastingFrom Wikipedia, the free encyclopedia

FM Radio Broadcasting : Big Picture in Full Electromagnetic Spectrum

A commercial ! kW FM radio transmitter "uilt in the late #$%&s' (t "elongs to FM radio station )W*R in

+as egas, *e-ada, .SA, and "roadcasts at a fre/uency of $!'! M01'

FM broadcastingis a 0F"roadcastingtechnology, pioneered "y Ed2in 0o2ard Armstrong,2hich usesfre/uency modulation3FM4 to pro-idehigh5fidelitysound o-er "roadcastradio' 6he

term 7FM "and7 descri"es the fre/uency "and in a gi-en country 2hich is dedicated to FM
https://en.wikipedia.org/wiki/VHFhttps://en.wikipedia.org/wiki/VHFhttps://en.wikipedia.org/wiki/Broadcastinghttps://en.wikipedia.org/wiki/Broadcastinghttps://en.wikipedia.org/wiki/Edwin_Howard_Armstronghttps://en.wikipedia.org/wiki/Edwin_Howard_Armstronghttps://en.wikipedia.org/wiki/Frequency_modulationhttps://en.wikipedia.org/wiki/Frequency_modulationhttps://en.wikipedia.org/wiki/High_fidelityhttps://en.wikipedia.org/wiki/High_fidelityhttps://en.wikipedia.org/wiki/Radiohttps://en.wikipedia.org/wiki/Radiohttps://en.wikipedia.org/wiki/Broadcastinghttps://en.wikipedia.org/wiki/Edwin_Howard_Armstronghttps://en.wikipedia.org/wiki/Frequency_modulationhttps://en.wikipedia.org/wiki/High_fidelityhttps://en.wikipedia.org/wiki/Radiohttps://en.wikipedia.org/wiki/VHF


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"roadcasting' 6his term is slightly misleading, as it e/uates a modulation method 2ith a range offre/uencies'

Contents

8hide9

# Broadcast "ands

Modulation characteristics

o '# Modulation

o ' Pre5emphasis and de5emphasis

o ' Stereo FM

o '; ?ol"y FM

?istance co-ered "y stereo FM transmission

; Adoption of FM "roadcasting

o ;'# .nited States

o ;' Europe

;''# .nited )ingdom

;'' (taly

;'' @reece

o ;' Australia

o ;'; *e2 ealand

o ;'! 6urkey

o ;'> =ther countries

o ;' (6. Conferences a"out FM

! Small5scale use of the FM "roadcast "and

o !'# Consumer use of FM transmitters

o

!' Micro"roadcasting
https://en.wikipedia.org/wiki/FM_broadcastinghttps://en.wikipedia.org/wiki/FM_broadcasting#Broadcast_bandshttps://en.wikipedia.org/wiki/FM_broadcasting#Modulation_characteristicshttps://en.wikipedia.org/wiki/FM_broadcasting#Modulationhttps://en.wikipedia.org/wiki/FM_broadcasting#Pre-emphasis_and_de-emphasishttps://en.wikipedia.org/wiki/FM_broadcasting#Stereo_FMhttps://en.wikipedia.org/wiki/FM_broadcasting#Quadraphonic_FMhttps://en.wikipedia.org/wiki/FM_broadcasting#Other_subcarrier_serviceshttps://en.wikipedia.org/wiki/FM_broadcasting#Dolby_FMhttps://en.wikipedia.org/wiki/FM_broadcasting#Distance_covered_by_stereo_FM_transmissionhttps://en.wikipedia.org/wiki/FM_broadcasting#Adoption_of_FM_broadcastinghttps://en.wikipedia.org/wiki/FM_broadcasting#United_Stateshttps://en.wikipedia.org/wiki/FM_broadcasting#Europehttps://en.wikipedia.org/wiki/FM_broadcasting#United_Kingdomhttps://en.wikipedia.org/wiki/FM_broadcasting#Italyhttps://en.wikipedia.org/wiki/FM_broadcasting#Greecehttps://en.wikipedia.org/wiki/FM_broadcasting#Australiahttps://en.wikipedia.org/wiki/FM_broadcasting#New_Zealandhttps://en.wikipedia.org/wiki/FM_broadcasting#Turkeyhttps://en.wikipedia.org/wiki/FM_broadcasting#Other_countrieshttps://en.wikipedia.org/wiki/FM_broadcasting#ITU_Conferences_about_FMhttps://en.wikipedia.org/wiki/FM_broadcasting#Small-scale_use_of_the_FM_broadcast_bandhttps://en.wikipedia.org/wiki/FM_broadcasting#Consumer_use_of_FM_transmittershttps://en.wikipedia.org/wiki/FM_broadcasting#Microbroadcastinghttps://en.wikipedia.org/wiki/FM_broadcastinghttps://en.wikipedia.org/wiki/FM_broadcasting#Broadcast_bandshttps://en.wikipedia.org/wiki/FM_broadcasting#Modulation_characteristicshttps://en.wikipedia.org/wiki/FM_broadcasting#Modulationhttps://en.wikipedia.org/wiki/FM_broadcasting#Pre-emphasis_and_de-emphasishttps://en.wikipedia.org/wiki/FM_broadcasting#Stereo_FMhttps://en.wikipedia.org/wiki/FM_broadcasting#Quadraphonic_FMhttps://en.wikipedia.org/wiki/FM_broadcasting#Other_subcarrier_serviceshttps://en.wikipedia.org/wiki/FM_broadcasting#Dolby_FMhttps://en.wikipedia.org/wiki/FM_broadcasting#Distance_covered_by_stereo_FM_transmissionhttps://en.wikipedia.org/wiki/FM_broadcasting#Adoption_of_FM_broadcastinghttps://en.wikipedia.org/wiki/FM_broadcasting#United_Stateshttps://en.wikipedia.org/wiki/FM_broadcasting#Europehttps://en.wikipedia.org/wiki/FM_broadcasting#United_Kingdomhttps://en.wikipedia.org/wiki/FM_broadcasting#Italyhttps://en.wikipedia.org/wiki/FM_broadcasting#Greecehttps://en.wikipedia.org/wiki/FM_broadcasting#Australiahttps://en.wikipedia.org/wiki/FM_broadcasting#New_Zealandhttps://en.wikipedia.org/wiki/FM_broadcasting#Turkeyhttps://en.wikipedia.org/wiki/FM_broadcasting#Other_countrieshttps://en.wikipedia.org/wiki/FM_broadcasting#ITU_Conferences_about_FMhttps://en.wikipedia.org/wiki/FM_broadcasting#Small-scale_use_of_the_FM_broadcast_bandhttps://en.wikipedia.org/wiki/FM_broadcasting#Consumer_use_of_FM_transmittershttps://en.wikipedia.org/wiki/FM_broadcasting#Microbroadcasting


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o !' Clandestine use of FM transmitters

> See also

o >'# FM "roadcasting "y country

o >' FM "roadcasting 3technical4

o >' +ists

o >'; 0istory

References

% EDternal links

Broadcast bands8edit9Main article:FM broadcast band

6hroughout the 2orld, the FM "roadcast "and falls 2ithin the 0Fpart of the radio spectrum'.sually %'! to #&%'& M01 is used,8#9or some portion thereof, 2ith fe2 eDceptions:

(n the former So-iet repu"lics, and some former Eastern Bloccountries, the older >!

; M01 "and is also used' Assigned fre/uencies are at inter-als of & k01' 6his "and,sometimes referred to as the =(R6"and, is slo2ly "eing phased out in many countries' (nthose countries the %'!#&%'& M01 "and is referred to as theCC(R"and'

(n apan,the "and >$& M01 is used'

6he fre/uency of an FM "roadcast station 3more strictly its assigned nominal center fre/uency4 isusually an eDact multiple of #&& k01' (n most ofSouth )orea,the Americasand the Cari""ean,only odd multiples are used' (n some parts of Europe,@reenlandandAfrica, only e-en multiplesare used' (n the .) odd or e-en are used' (n (taly,multiples of !& k01 are used' 6here are otherunusual and o"solete standards in some countries, including &'&, &', &'&, &'&;, &'!, and&' M01' 0o2e-er, to minimise cross5channel interference, stations operating from the same orgeographically close transmitters tend to keep to at least a &'! M01 fre/uency separation e-en2hen closer spacing is technically permitted, 2ith closer tunings reser-ed for more distantlyspaced transmitters as potentially interfering signals are already more attenuated and so ha-eless effect on neigh"ouring fre/uencies' RCA stereo models use multiples of &' M01, starting at%'!& and ending at #&'$&'8citation needed9

Modulation characteristics8edit9Modulation8edit9

Fre/uency modulationor FM is a form of modulation 2hich con-eys information "y -arying thefre/uency of acarrier 2a-eG the older amplitude modulationor AM -aries the amplitude of thecarrier, 2ith its fre/uency remaining constant' With FM,fre/uency de-iationfrom the assignedcarrier fre/uency at any instant is directly proportional to the amplitude of the input signal,determining the instantaneous fre/uency of the transmitted signal' Because transmitted FMsignals use more "and2idththan AM signals, this form of modulation is commonly used 2ith thehigher 30For .0F4 fre/uencies used "y 6, theFM "roadcast "and, and land mo"ile radiosystems'

Pre-emphasis and de-emphasis8edit9
https://en.wikipedia.org/wiki/FM_broadcasting#Clandestine_use_of_FM_transmittershttps://en.wikipedia.org/wiki/FM_broadcasting#See_alsohttps://en.wikipedia.org/wiki/FM_broadcasting#FM_broadcasting_by_countryhttps://en.wikipedia.org/wiki/FM_broadcasting#FM_broadcasting_.28technical.29https://en.wikipedia.org/wiki/FM_broadcasting#Listshttps://en.wikipedia.org/wiki/FM_broadcasting#Historyhttps://en.wikipedia.org/wiki/FM_broadcasting#Referenceshttps://en.wikipedia.org/wiki/FM_broadcasting#External_linkshttps://en.wikipedia.org/w/index.php?title=FM_broadcasting&action=edit&section=1https://en.wikipedia.org/wiki/FM_broadcast_bandhttps://en.wikipedia.org/wiki/FM_broadcast_bandhttps://en.wikipedia.org/wiki/VHFhttps://en.wikipedia.org/wiki/Radio_spectrumhttps://en.wikipedia.org/wiki/FM_broadcasting#cite_note-1https://en.wikipedia.org/wiki/Commonwealth_of_Independent_Stateshttps://en.wikipedia.org/wiki/Eastern_Blochttps://en.wikipedia.org/wiki/Eastern_Blochttps://en.wikipedia.org/wiki/OIRThttps://en.wikipedia.org/wiki/Comit%C3%A9_consultatif_international_pour_la_radiohttps://en.wikipedia.org/wiki/Comit%C3%A9_consultatif_international_pour_la_radiohttps://en.wikipedia.org/wiki/Japanhttps://en.wikipedia.org/wiki/Japanhttps://en.wikipedia.org/wiki/South_Koreahttps://en.wikipedia.org/wiki/South_Koreahttps://en.wikipedia.org/wiki/The_Americashttps://en.wikipedia.org/wiki/The_Americashttps://en.wikipedia.org/wiki/The_Americashttps://en.wikipedia.org/wiki/Caribbeanhttps://en.wikipedia.org/wiki/Europehttps://en.wikipedia.org/wiki/Greenlandhttps://en.wikipedia.org/wiki/Greenlandhttps://en.wikipedia.org/wiki/Africahttps://en.wikipedia.org/wiki/Italyhttps://en.wikipedia.org/wiki/Italyhttps://en.wikipedia.org/wiki/Wikipedia:Citation_neededhttps://en.wikipedia.org/wiki/Wikipedia:Citation_neededhttps://en.wikipedia.org/wiki/Wikipedia:Citation_neededhttps://en.wikipedia.org/w/index.php?title=FM_broadcasting&action=edit&section=2https://en.wikipedia.org/w/index.php?title=FM_broadcasting&action=edit&section=3https://en.wikipedia.org/wiki/Frequency_modulationhttps://en.wikipedia.org/wiki/Carrier_wavehttps://en.wikipedia.org/wiki/Carrier_wavehttps://en.wikipedia.org/wiki/Amplitude_modulationhttps://en.wikipedia.org/wiki/Frequency_deviationhttps://en.wikipedia.org/wiki/Frequency_deviationhttps://en.wikipedia.org/wiki/Bandwidth_(signal_processing)https://en.wikipedia.org/wiki/Bandwidth_(signal_processing)https://en.wikipedia.org/wiki/VHFhttps://en.wikipedia.org/wiki/UHFhttps://en.wikipedia.org/wiki/TVhttps://en.wikipedia.org/wiki/FM_broadcast_bandhttps://en.wikipedia.org/wiki/FM_broadcast_bandhttps://en.wikipedia.org/wiki/Land_mobile_radio_systemhttps://en.wikipedia.org/wiki/Land_mobile_radio_systemhttps://en.wikipedia.org/w/index.php?title=FM_broadcasting&action=edit&section=4https://en.wikipedia.org/wiki/FM_broadcasting#Clandestine_use_of_FM_transmittershttps://en.wikipedia.org/wiki/FM_broadcasting#See_alsohttps://en.wikipedia.org/wiki/FM_broadcasting#FM_broadcasting_by_countryhttps://en.wikipedia.org/wiki/FM_broadcasting#FM_broadcasting_.28technical.29https://en.wikipedia.org/wiki/FM_broadcasting#Listshttps://en.wikipedia.org/wiki/FM_broadcasting#Historyhttps://en.wikipedia.org/wiki/FM_broadcasting#Referenceshttps://en.wikipedia.org/wiki/FM_broadcasting#External_linkshttps://en.wikipedia.org/w/index.php?title=FM_broadcasting&action=edit&section=1https://en.wikipedia.org/wiki/FM_broadcast_bandhttps://en.wikipedia.org/wiki/VHFhttps://en.wikipedia.org/wiki/Radio_spectrumhttps://en.wikipedia.org/wiki/FM_broadcasting#cite_note-1https://en.wikipedia.org/wiki/Commonwealth_of_Independent_Stateshttps://en.wikipedia.org/wiki/Eastern_Blochttps://en.wikipedia.org/wiki/OIRThttps://en.wikipedia.org/wiki/Comit%C3%A9_consultatif_international_pour_la_radiohttps://en.wikipedia.org/wiki/Japanhttps://en.wikipedia.org/wiki/South_Koreahttps://en.wikipedia.org/wiki/The_Americashttps://en.wikipedia.org/wiki/Caribbeanhttps://en.wikipedia.org/wiki/Europehttps://en.wikipedia.org/wiki/Greenlandhttps://en.wikipedia.org/wiki/Africahttps://en.wikipedia.org/wiki/Italyhttps://en.wikipedia.org/wiki/Wikipedia:Citation_neededhttps://en.wikipedia.org/w/index.php?title=FM_broadcasting&action=edit&section=2https://en.wikipedia.org/w/index.php?title=FM_broadcasting&action=edit&section=3https://en.wikipedia.org/wiki/Frequency_modulationhttps://en.wikipedia.org/wiki/Carrier_wavehttps://en.wikipedia.org/wiki/Amplitude_modulationhttps://en.wikipedia.org/wiki/Frequency_deviationhttps://en.wikipedia.org/wiki/Bandwidth_(signal_processing)https://en.wikipedia.org/wiki/VHFhttps://en.wikipedia.org/wiki/UHFhttps://en.wikipedia.org/wiki/TVhttps://en.wikipedia.org/wiki/FM_broadcast_bandhttps://en.wikipedia.org/wiki/Land_mobile_radio_systemhttps://en.wikipedia.org/wiki/Land_mobile_radio_systemhttps://en.wikipedia.org/w/index.php?title=FM_broadcasting&action=edit&section=4


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Randomnoisehas a triangularspectraldistri"ution in an FM system, 2ith the effect that noiseoccurs predominantly at the highest audiofre/uencies2ithin the "ase"and' 6his can "e offset, toa limited eDtent, "y "oosting the high fre/uencies "efore transmissionand reducing them "y acorresponding amount in the recei-er' Reducing the high audio fre/uencies in the recei-er alsoreduces the high5fre/uency noise' 6hese processes of "oosting and then reducing certainfre/uencies are kno2n aspre5emphasisandde5emphasis, respecti-ely'

6he amount of pre5emphasis and de5emphasis used is defined "y the time constantof asimple RC filtercircuit' (n most of the 2orld a !& Hs time constant is used' (n the AmericasandSouth )orea, ! Hs is used' 6his applies to "othmonoand stereotransmissions' For stereo,pre5emphasis is applied to the left and right channels "eforemultipleDing'

6he amount of pre5emphasis that can "e applied is limited "y the fact that many forms ofcontemporary music contain more high5fre/uency energy than the musical styles 2hich pre-ailedat the "irth of FM "roadcasting' 6hey cannot "e pre5emphasi1ed as much "ecause it 2ouldcause eDcessi-e de-iation of the FM carrier' Systems more modern than FM "roadcasting tendto use either programme5dependent -aria"le pre5emphasisG e'g', d"Din theB6SC6 soundsystem, or none at all'

Stereo FM8edit9(n the late #$!&s, se-eral systems to add stereoto FM radio 2ere considered "y theFCC'(ncluded 2ere systems from #; proponents including Cros"y, 0alstead, Electrical and Musical(ndustries, +td 3EM(4, enith, and @eneral Electric' 6he indi-idual systems 2ere e-aluated fortheir strengths and 2eaknesses during field tests in .nionto2n, Pennsyl-aniausing )?)A5FMinPitts"urgh as the originating station' 6he Cros"y system2as reIected "y the FCC "ecause it 2asincompati"le 2ith eDisting su"sidiary communications authori1ation3SCA4 ser-ices 2hich used-arious su"carrier fre/uencies including ;# and > k01' Many re-enue5star-ed FM stations usedSCAs for 7storecasting7 and other non5"roadcast purposes' 6he 0alstead system 2as reIecteddue to lack of high fre/uency stereo separation and reduction in the main channel signal5to5noiseratio' 6he @E and enith systems, so similar that they 2ere considered theoretically identical,2ere formally appro-ed "y the FCC in April #$># as the standard stereo FM "roadcasting

method in the .nited States and later adopted "y most other countries'89

(t is important that stereo "roadcasts "e compati"le 2ith mono recei-ers' For this reason, the left3+4 and right 3R4 channels are alge"raically encoded into sum 3+JR4 and difference 3+KR4 signals'A mono recei-er 2ill use Iust the +JR signal so the listener 2ill hear "oth channels through thesingle loudspeaker' A stereo recei-er 2ill add the difference signal to the sum signal to reco-erthe left channel, and su"tract the difference signal from the sum to reco-er the right channel'

6he 3+JR4 Main channel signal is transmitted as "ase"and audiolimited to the range of & 01 to#! k01' 6he 3+KR4 signal is amplitude modulated onto a % k01 dou"le5side"and suppressed5carrier3?SB5SC4 signal occupying the "ase"and range of to ! k01'

A #$ k01 pilot tone, at eDactly half the % k01su"5carrierfre/uency and 2ith a precise phaserelationship to it, as defined "y the formula "elo2, is also generated' 6his is transmitted at %#&L

of o-erallmodulationle-el and used "y the recei-er to regenerate the % k01 su"5carrier2ith thecorrect phase'

6he final multipleD signal from the stereo generator contains the Main Channel 3+JR4, the pilottone, and the su"5channel 3+KR4' 6his composite signal, along 2ith any other su"5carriers,modulates the FM transmitter'

6he instantaneous de-iation of the transmitter carrier fre/uency due to the stereo audio and pilottone 3at #&L modulation4 is

89
https://en.wikipedia.org/wiki/Noisehttps://en.wikipedia.org/wiki/Noisehttps://en.wikipedia.org/wiki/Frequency_spectrumhttps://en.wikipedia.org/wiki/Frequencyhttps://en.wikipedia.org/wiki/Frequencyhttps://en.wikipedia.org/wiki/Basebandhttps://en.wikipedia.org/wiki/Transmission_(telecommunications)https://en.wikipedia.org/wiki/Transmission_(telecommunications)https://en.wikipedia.org/wiki/Preemphasishttps://en.wikipedia.org/wiki/Preemphasishttps://en.wikipedia.org/wiki/Preemphasishttps://en.wikipedia.org/wiki/Deemphasishttps://en.wikipedia.org/wiki/Deemphasishttps://en.wikipedia.org/wiki/Time_constanthttps://en.wikipedia.org/wiki/Time_constanthttps://en.wikipedia.org/wiki/RC_circuithttps://en.wikipedia.org/wiki/RC_circuithttps://en.wikipedia.org/wiki/South_Koreahttps://en.wikipedia.org/wiki/South_Koreahttps://en.wikipedia.org/wiki/Monauralhttps://en.wikipedia.org/wiki/Monauralhttps://en.wikipedia.org/wiki/Stereophonic_soundhttps://en.wikipedia.org/wiki/Stereophonic_soundhttps://en.wikipedia.org/wiki/Multiplexinghttps://en.wikipedia.org/wiki/Carrier_wavehttps://en.wikipedia.org/wiki/Dbx_(noise_reduction)https://en.wikipedia.org/wiki/Multichannel_television_soundhttps://en.wikipedia.org/wiki/Multichannel_television_soundhttps://en.wikipedia.org/w/index.php?title=FM_broadcasting&action=edit&section=5https://en.wikipedia.org/wiki/Stereohttps://en.wikipedia.org/wiki/Federal_Communications_Commissionhttps://en.wikipedia.org/wiki/Federal_Communications_Commissionhttps://en.wikipedia.org/wiki/EMIhttps://en.wikipedia.org/wiki/Uniontown,_Pennsylvaniahttps://en.wikipedia.org/wiki/WLTJhttps://en.wikipedia.org/wiki/WLTJhttps://en.wikipedia.org/wiki/Crosby_systemhttps://en.wikipedia.org/wiki/Subsidiary_communications_authorizationhttps://en.wikipedia.org/wiki/FM_broadcasting#cite_note-2https://en.wikipedia.org/wiki/Soundhttps://en.wikipedia.org/wiki/Soundhttps://en.wikipedia.org/wiki/Double-sideband_suppressed-carrierhttps://en.wikipedia.org/wiki/Double-sideband_suppressed-carrierhttps://en.wikipedia.org/wiki/Pilot_tonehttps://en.wikipedia.org/wiki/Sub-carrierhttps://en.wikipedia.org/wiki/Sub-carrierhttps://en.wikipedia.org/wiki/Modulationhttps://en.wikipedia.org/wiki/Modulationhttps://en.wikipedia.org/wiki/Sub-carrierhttps://en.wikipedia.org/wiki/FM_broadcasting#cite_note-3https://en.wikipedia.org/wiki/Noisehttps://en.wikipedia.org/wiki/Frequency_spectrumhttps://en.wikipedia.org/wiki/Frequencyhttps://en.wikipedia.org/wiki/Basebandhttps://en.wikipedia.org/wiki/Transmission_(telecommunications)https://en.wikipedia.org/wiki/Preemphasishttps://en.wikipedia.org/wiki/Deemphasishttps://en.wikipedia.org/wiki/Time_constanthttps://en.wikipedia.org/wiki/RC_circuithttps://en.wikipedia.org/wiki/South_Koreahttps://en.wikipedia.org/wiki/Monauralhttps://en.wikipedia.org/wiki/Stereophonic_soundhttps://en.wikipedia.org/wiki/Multiplexinghttps://en.wikipedia.org/wiki/Carrier_wavehttps://en.wikipedia.org/wiki/Dbx_(noise_reduction)https://en.wikipedia.org/wiki/Multichannel_television_soundhttps://en.wikipedia.org/w/index.php?title=FM_broadcasting&action=edit&section=5https://en.wikipedia.org/wiki/Stereohttps://en.wikipedia.org/wiki/Federal_Communications_Commissionhttps://en.wikipedia.org/wiki/EMIhttps://en.wikipedia.org/wiki/Uniontown,_Pennsylvaniahttps://en.wikipedia.org/wiki/WLTJhttps://en.wikipedia.org/wiki/Crosby_systemhttps://en.wikipedia.org/wiki/Subsidiary_communications_authorizationhttps://en.wikipedia.org/wiki/FM_broadcasting#cite_note-2https://en.wikipedia.org/wiki/Soundhttps://en.wikipedia.org/wiki/Double-sideband_suppressed-carrierhttps://en.wikipedia.org/wiki/Double-sideband_suppressed-carrierhttps://en.wikipedia.org/wiki/Pilot_tonehttps://en.wikipedia.org/wiki/Sub-carrierhttps://en.wikipedia.org/wiki/Modulationhttps://en.wikipedia.org/wiki/Sub-carrierhttps://en.wikipedia.org/wiki/FM_broadcasting#cite_note-3


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2here A and B are the pre5emphasi1ed left and right audio signals and #$ k01 is thefre/uency of the pilot tone' Slight -ariations in the peak de-iation may occur in the presenceof other su"carriers or "ecause of local regulations'

Con-erting the multipleD signal "ack into left and right audio signals is performed "y adecoder, "uilt into stereo recei-ers'

(n order to preser-e stereo separation and signal5to5noise parameters, it is normal practice toapply pre5emphasis to the left and right channels "efore encoding, and to apply de5emphasisat the recei-er after decoding'

Stereo FM signals are more suscepti"le to noiseand multipath distortionthan are mono FMsignals'8;9

(n addition, for a gi-en RF le-el at the recei-er, the signal5to5noise ratiofor the stereo signal2ill "e 2orse than for the mono recei-er' For this reason many stereo FM recei-ers include astereoNmono s2itch to allo2 listening in mono 2hen reception conditions are less than ideal,and most car radios are arranged to reduce the separation as the signal5to5noise ratio2orsens, e-entually going to mono 2hile still indicating a stereo signal is "eing recei-ed'

Quadraphonic FM8edit9(n #$>$, +ouis ?orrenin-ented the


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6ypical spectrum of composite "ase"and signal

FM "roadcasting has included SCA capa"ility since its inception, as it 2as seen as anotherser-ice 2hich licensees could use to create additional income'8>9(nitially the users of SCAser-ices 2ere pri-ate analog audio channels 2hich could "e used internally or rentedout, foreDample Mu1aktype ser-ices' Radio reading ser-icesfor the "lind"ecame a common use,and remain so, and there 2ereeDperiments2ith /uadraphonicsound' (f a station does not"roadcast in stereo, e-erything from k01 on up can "e used for other ser-ices' 6he guard"andaround #$ k01 3; k014 must still "e maintained, so as not to trigger stereo decoderson recei-ers' (f there is stereo, there 2ill typically "e a guard "and "et2een the upper limit ofthe ?SBSC stereo signal 3! k014 and the lo2er limit of any other su"carrier'

?igitalser-ices are no2 also a-aila"le' A ! k01 su"carrier 3phase lockedto the

thirdharmonicof the stereo pilot tone4 is used to carry a lo25"and2idth digital Radio ?ataSystemsignal, pro-iding eDtra features such asAlternati-e Fre/uency3AF4 and *et2ork3**4' 6his narro2"andsignal runs at only ##%'! "its per second,thus is only suita"le forteDt' A fe2 proprietarysystems are used for pri-ate communications' A -ariant ofR?Sis the*orth AmericanRB?Sor 7smart radio7 system' (n @ermany the analog AR( system 2as usedprior to R?S for "roadcasting traffic announcements to motorists 32ithout distur"ing otherlisteners4' Plans to use AR( for other European countries led to the de-elopment of R?S as amore po2erful system' R?S is designed to "e capa"le of "eing used alongside AR( despiteusing identical su"carrier fre/uencies'

(n the.nited States, digital radioser-ices are "eing deployed 2ithin the FM "and rather thanusing Eureka #;or the apanese standard (S?B'6his in5"and on5channelapproach, as doalldigital radiotechni/ues, makes use of ad-anced compressed audio' 6he

proprietary iBi/uitysystem, "randedas 70? Radio7, currently is authori1ed for 7hy"rid7 modeoperation, 2herein "oth the con-entional analog FM carrier and digital side"andsu"carriersare transmitted' E-entually, presuming 2idespread deployment of 0? Radiorecei-ers, theanalog ser-ices could theoretically "e discontinued and the FM "and "ecome all digital'

(n the .nited States, ser-ices 3other than stereo, /uad and R?S4 using su"carriers aresometimes referred to as su"sidiary communications authori1ation3SCA4 ser-ices' .ses forsuch su"carriers include "ookNne2spaper reading ser-ices for "lind listeners, pri-ate datatransmission ser-ices 3for eDample sending stock market information to stock"rokers orstolen credit card num"er "lacklists to stores 8citation needed94 su"scription commercial5free"ackground music ser-ices for shops, paging 37"eeper74 ser-ices and pro-iding a programfeed for AM transmitters of AMNFM stations' SCA su"carriers are typically > k01 and$ k01'

Dolby FM8edit9
https://en.wikipedia.org/wiki/FM_broadcasting#cite_note-6https://en.wikipedia.org/wiki/Rentinghttps://en.wikipedia.org/wiki/Muzak_(brand)https://en.wikipedia.org/wiki/Radio_reading_servicehttps://en.wikipedia.org/wiki/Blindnesshttps://en.wikipedia.org/wiki/Experimenthttps://en.wikipedia.org/wiki/Experimenthttps://en.wikipedia.org/wiki/Quadraphonichttps://en.wikipedia.org/wiki/Guard_bandhttps://en.wikipedia.org/wiki/Guard_bandhttps://en.wikipedia.org/wiki/Digital_datahttps://en.wikipedia.org/wiki/Digital_datahttps://en.wikipedia.org/wiki/Phase-locked_loophttps://en.wikipedia.org/wiki/Harmonichttps://en.wikipedia.org/wiki/Harmonichttps://en.wikipedia.org/wiki/Radio_Data_Systemhttps://en.wikipedia.org/wiki/Radio_Data_Systemhttps://en.wikipedia.org/wiki/Radio_Data_Systemhttps://en.wikipedia.org/wiki/Alternative_frequencyhttps://en.wikipedia.org/wiki/Alternative_frequencyhttps://en.wikipedia.org/wiki/Narrowbandhttps://en.wikipedia.org/wiki/Narrowbandhttps://en.wikipedia.org/wiki/Bits_per_secondhttps://en.wikipedia.org/wiki/Bits_per_secondhttps://en.wikipedia.org/wiki/Proprietary_protocolhttps://en.wikipedia.org/wiki/Proprietary_protocolhttps://en.wikipedia.org/wiki/Radio_Data_Systemhttps://en.wikipedia.org/wiki/Radio_Data_Systemhttps://en.wikipedia.org/wiki/Radio_Data_Systemhttps://en.wikipedia.org/wiki/Radio_Data_Systemhttps://en.wikipedia.org/wiki/United_Stateshttps://en.wikipedia.org/wiki/United_Stateshttps://en.wikipedia.org/wiki/Digital_radiohttps://en.wikipedia.org/wiki/Digital_Audio_Broadcastinghttps://en.wikipedia.org/wiki/ISDBhttps://en.wikipedia.org/wiki/ISDBhttps://en.wikipedia.org/wiki/In-band_on-channelhttps://en.wikipedia.org/wiki/Digital_radiohttps://en.wikipedia.org/wiki/Digital_radiohttps://en.wikipedia.org/wiki/Digital_radiohttps://en.wikipedia.org/wiki/Audio_compression_(data)https://en.wikipedia.org/wiki/IBiquityhttps://en.wikipedia.org/wiki/Brandhttps://en.wikipedia.org/wiki/HD_Radiohttps://en.wikipedia.org/wiki/Sidebandhttps://en.wikipedia.org/wiki/HD_Radiohttps://en.wikipedia.org/wiki/Subsidiary_communications_authorityhttps://en.wikipedia.org/wiki/Wikipedia:Citation_neededhttps://en.wikipedia.org/wiki/Wikipedia:Citation_neededhttps://en.wikipedia.org/wiki/Wikipedia:Citation_neededhttps://en.wikipedia.org/w/index.php?title=FM_broadcasting&action=edit&section=8https://en.wikipedia.org/wiki/FM_broadcasting#cite_note-6https://en.wikipedia.org/wiki/Rentinghttps://en.wikipedia.org/wiki/Muzak_(brand)https://en.wikipedia.org/wiki/Radio_reading_servicehttps://en.wikipedia.org/wiki/Blindnesshttps://en.wikipedia.org/wiki/Experimenthttps://en.wikipedia.org/wiki/Quadraphonichttps://en.wikipedia.org/wiki/Guard_bandhttps://en.wikipedia.org/wiki/Guard_bandhttps://en.wikipedia.org/wiki/Digital_datahttps://en.wikipedia.org/wiki/Phase-locked_loophttps://en.wikipedia.org/wiki/Harmonichttps://en.wikipedia.org/wiki/Radio_Data_Systemhttps://en.wikipedia.org/wiki/Radio_Data_Systemhttps://en.wikipedia.org/wiki/Alternative_frequencyhttps://en.wikipedia.org/wiki/Narrowbandhttps://en.wikipedia.org/wiki/Bits_per_secondhttps://en.wikipedia.org/wiki/Proprietary_protocolhttps://en.wikipedia.org/wiki/Radio_Data_Systemhttps://en.wikipedia.org/wiki/Radio_Data_Systemhttps://en.wikipedia.org/wiki/United_Stateshttps://en.wikipedia.org/wiki/Digital_radiohttps://en.wikipedia.org/wiki/Digital_Audio_Broadcastinghttps://en.wikipedia.org/wiki/ISDBhttps://en.wikipedia.org/wiki/In-band_on-channelhttps://en.wikipedia.org/wiki/Digital_radiohttps://en.wikipedia.org/wiki/Audio_compression_(data)https://en.wikipedia.org/wiki/IBiquityhttps://en.wikipedia.org/wiki/Brandhttps://en.wikipedia.org/wiki/HD_Radiohttps://en.wikipedia.org/wiki/Sidebandhttps://en.wikipedia.org/wiki/HD_Radiohttps://en.wikipedia.org/wiki/Subsidiary_communications_authorityhttps://en.wikipedia.org/wiki/Wikipedia:Citation_neededhttps://en.wikipedia.org/w/index.php?title=FM_broadcasting&action=edit&section=8


7/12

A commercially unsuccessful noise reductionsystem used 2ith FM radio in some countriesduring the late #$&s, ?ol"y FM 2as similar to?ol"y B89"ut used a modified ! Hs pre5emphasis time constant and a fre/uency selecti-ecompandingarrangement to reducenoise'

A similar system named 0igh Com FM2as tested in @ermany "et2een uly #$$ and

?ecem"er #$%# "y (R6' (t 2as "ased on the6elefunken0igh Com"road"and compandersystem, "ut ne-er introduced commercially in FM "roadcasting' 8%9

Further information: Dolby noise reduction system

Distance covered by stereo FM transmission8edit9

6he range of mono FM transmission is related to thetransmitterOs RF po2er, theantennagain, and antenna height' 6he .'S' FCC pu"lishes cur-es that aid in calculation of thismaDimum distance as a function of signal strength at the recei-ing location'

For stereo FM, the range is some2hat 8citation needed9reduced' 6his is due to the need to lo2erthe modulation indeDof the main 3sum4 signal to accommodate the presence of the % k01?SB5SC 3dou"le side5"and suppressed5carrier4 su"carrier and #$ k01 pilot tone'

Many FM stations, especially those located in se-ere multipath areas, use eDtraaudiocompressionto keep essential sound a"o-e the "ackground noise for listeners, occasionallyat the eDpense of o-erall percei-ed sound /uality' (n such instances, ho2e-er, this techni/ueis often surprisingly effecti-e in increasing the stationOs useful range' 8citation needed9

Adoption of FM broadcasting8edit9United States8edit9

?espite FM ha-ing "een patented in #$, commercial FM "roadcasting did not "egin untilthe late #$&s, 2hen it 2as initiated "y a handful of early pioneer stations including W%0),Buffalo, *e2 Qork 3no2 W6SS4G W#=NW@6R, PaDton Massachusetts 3closed do2n a"out

#$!4G W#S+NW#PWNW?RC5FM, Meriden, Connecticut 3no2 W0C*4GWM*N)ECCNWFM*, Alpine, *e2 ersey 3o2ned "y Ed2in Armstrong himself, closeddo2n upon ArmstrongOs death in #$!;4GW


8/12

and aid reception pro"lems in "uildings, during thunderstorms, and near high5-oltage 2ires'Some of these stations no2 emphasi1e their presence on the FM dial'4

Europe8edit9

6he medium 2a-e"and 3kno2n as theAM"and "ecause most stations using it employamplitude modulation in *orth America4 is o-ercro2ded8citation needed9in Western Europe, leadingto interference pro"lems and, as a result, many MW fre/uencies are suita"le only for speech"roadcasting'

Belgium, the*etherlands, ?enmarkand particularly@ermany2ere among the first countriesto adopt FM on a 2idespread scale' Among the reasons for this 2ere:

#' 6hemedium 2a-e"and in Western Europe "ecame o-ercro2ded after World War ((,mainly due to the "est a-aila"le medium 2a-e fre/uencies "eing used at high po2erle-els "y the Allied =ccupation Forces, "oth for "roadcastingentertainment to theirtroopsand for "roadcastingCold Warpropaganda across the (ron Curtain'

' After World War ((, "roadcasting fre/uencies 2ere reorgani1ed and reallocated "y

delegates of the -ictorious countries in the Copenhagen Fre/uency Plan' @erman"roadcasters 2ere left 2ith only t2o remaining AM fre/uencies and 2ere forced tolook to FM for eDpansion'

Pu"lic ser-ice "roadcasters in(relandand Australia 2ere far slo2er at adopting FM radiothan those in either*orth Americaor continental Europe'

United ingdom8edit9

(n the.nited )ingdom, theBBC"egan FM "roadcasting in #$!!, 2ith three nationalnet2orks: the+ight Programme,6hird Programmeand 0ome Ser-ice' 6hese three net2orksused the su"5"and %%'&$;'> M01' 6he su"5"and $;'>$'> M01 2as later used for BBCand local commercial ser-ices'

0o2e-er, only 2hen commercial "roadcasting 2as introduced to the .) in #$ did the useof FM pick up in Britain' With the gradual clearance of other users 3nota"ly Pu"lic Ser-icessuch as police, fire and am"ulance4 and the eDtension of the FM "and to #&%'& M01"et2een #$%& and #$$!, FM eDpanded rapidly throughout the British (sles and effecti-elytook o-er from +W and MW as the deli-ery platform of choice for fiDed and porta"le domesticand -ehicle5"ased recei-ers' (n addition, =fcom3pre-iously the Radio Authority4 in the .)issues on demand Restricted Ser-ice +icences on FM and also on AM 3MW4 for short5termlocal5co-erage "roadcasting 2hich is open to anyone 2ho does not carry a prohi"ition andcan put up the appropriate licensing and royalty fees' (n & around ;!& such licences 2ereissued'

When the BBCOs radio net2orks 2ere renamed Radio ,Radio and Radio ;respecti-elyin #$>to coincide 2ith the launch of Radio #, the ne2 station 2as the only one of the main

four to not ha-e an FM fre/uency allocated, 2hich 2as the case for # years' (nstead, Radio# shared airtime 2ith Radio FM, on Saturday afternoons, Sunday e-enings, 2eekdaye-enings 3#&pm to midnight4 and Bank 0olidays' E-entually in #$%a fre/uency range of $5$$ M01 2as allocated as police relay transmitters 2ere mo-ed from the #&& M01 fre/uency,starting in +ondon "efore "eing "roadly completed "y #$%$' 8$9

!taly8edit9

(talyadopted FM "roadcast 2idely in the early #$&s 2hen the 7mo-ement for free radio7,de-eloped "y so5called 7pirates7, forced the recognition of free speech rights also throughthe use of 7free radio media such as Broadcast transmitters7, and took the case to theConstitutional Court of (taly' 6he court finally decided in fa-or of Free Radio' ust 2eeks afterthe courtOs final decision there 2as an 7FM radio "oom7 in-ol-ing small pri-ate radio stations

across the country' By the mid &s, e-ery city in (taly had a cro2ded FM radio spectrum'

"reece8edit9
https://en.wikipedia.org/w/index.php?title=FM_broadcasting&action=edit&section=12https://en.wikipedia.org/w/index.php?title=FM_broadcasting&action=edit&section=12https://en.wikipedia.org/wiki/Medium_wavehttps://en.wikipedia.org/wiki/Wikipedia:Citation_neededhttps://en.wikipedia.org/wiki/Wikipedia:Citation_neededhttps://en.wikipedia.org/wiki/Wikipedia:Citation_neededhttps://en.wikipedia.org/wiki/Belgiumhttps://en.wikipedia.org/wiki/Netherlandshttps://en.wikipedia.org/wiki/Netherlandshttps://en.wikipedia.org/wiki/Denmarkhttps://en.wikipedia.org/wiki/Germanyhttps://en.wikipedia.org/wiki/Germanyhttps://en.wikipedia.org/wiki/Medium_wavehttps://en.wikipedia.org/wiki/Medium_wavehttps://en.wikipedia.org/wiki/Medium_wavehttps://en.wikipedia.org/wiki/American_Forces_Networkhttps://en.wikipedia.org/wiki/American_Forces_Networkhttps://en.wikipedia.org/wiki/American_Forces_Networkhttps://en.wikipedia.org/wiki/Cold_Warhttps://en.wikipedia.org/wiki/Cold_Warhttps://en.wikipedia.org/wiki/Iron_Curtainhttps://en.wikipedia.org/wiki/Republic_of_Irelandhttps://en.wikipedia.org/wiki/Republic_of_Irelandhttps://en.wikipedia.org/wiki/North_Americahttps://en.wikipedia.org/wiki/North_Americahttps://en.wikipedia.org/wiki/Europehttps://en.wikipedia.org/w/index.php?title=FM_broadcasting&action=edit&section=13https://en.wikipedia.org/wiki/United_Kingdomhttps://en.wikipedia.org/wiki/United_Kingdomhttps://en.wikipedia.org/wiki/BBChttps://en.wikipedia.org/wiki/BBChttps://en.wikipedia.org/wiki/BBC_Light_Programmehttps://en.wikipedia.org/wiki/BBC_Light_Programmehttps://en.wikipedia.org/wiki/BBC_Light_Programmehttps://en.wikipedia.org/wiki/BBC_Third_Programmehttps://en.wikipedia.org/wiki/BBC_Home_Servicehttps://en.wikipedia.org/wiki/Ofcomhttps://en.wikipedia.org/wiki/BBC_Radio_2https://en.wikipedia.org/wiki/BBC_Radio_2https://en.wikipedia.org/wiki/BBC_Radio_3https://en.wikipedia.org/wiki/BBC_Radio_3https://en.wikipedia.org/wiki/BBC_Radio_4https://en.wikipedia.org/wiki/1967_in_British_radiohttps://en.wikipedia.org/wiki/BBC_Radio_1https://en.wikipedia.org/wiki/1987_in_British_radiohttps://en.wikipedia.org/wiki/1987_in_British_radiohttps://en.wikipedia.org/wiki/FM_broadcasting#cite_note-9https://en.wikipedia.org/w/index.php?title=FM_broadcasting&action=edit&section=14https://en.wikipedia.org/wiki/Italyhttps://en.wikipedia.org/w/index.php?title=FM_broadcasting&action=edit&section=15https://en.wikipedia.org/w/index.php?title=FM_broadcasting&action=edit&section=12https://en.wikipedia.org/wiki/Medium_wavehttps://en.wikipedia.org/wiki/Wikipedia:Citation_neededhttps://en.wikipedia.org/wiki/Belgiumhttps://en.wikipedia.org/wiki/Netherlandshttps://en.wikipedia.org/wiki/Denmarkhttps://en.wikipedia.org/wiki/Germanyhttps://en.wikipedia.org/wiki/Medium_wavehttps://en.wikipedia.org/wiki/American_Forces_Networkhttps://en.wikipedia.org/wiki/American_Forces_Networkhttps://en.wikipedia.org/wiki/Cold_Warhttps://en.wikipedia.org/wiki/Iron_Curtainhttps://en.wikipedia.org/wiki/Republic_of_Irelandhttps://en.wikipedia.org/wiki/North_Americahttps://en.wikipedia.org/wiki/Europehttps://en.wikipedia.org/w/index.php?title=FM_broadcasting&action=edit&section=13https://en.wikipedia.org/wiki/United_Kingdomhttps://en.wikipedia.org/wiki/BBChttps://en.wikipedia.org/wiki/BBC_Light_Programmehttps://en.wikipedia.org/wiki/BBC_Third_Programmehttps://en.wikipedia.org/wiki/BBC_Home_Servicehttps://en.wikipedia.org/wiki/Ofcomhttps://en.wikipedia.org/wiki/BBC_Radio_2https://en.wikipedia.org/wiki/BBC_Radio_3https://en.wikipedia.org/wiki/BBC_Radio_4https://en.wikipedia.org/wiki/1967_in_British_radiohttps://en.wikipedia.org/wiki/BBC_Radio_1https://en.wikipedia.org/wiki/1987_in_British_radiohttps://en.wikipedia.org/wiki/FM_broadcasting#cite_note-9https://en.wikipedia.org/w/index.php?title=FM_broadcasting&action=edit&section=14https://en.wikipedia.org/wiki/Italyhttps://en.wikipedia.org/w/index.php?title=FM_broadcasting&action=edit&section=15


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@reece2as another European country 2here the FM radio spectrum 2as used at first "y theso5called 7pirates7 3"oth in Athens and 6hessaloniki, the t2o maIor @reek cities4 in the mid&s, "efore any national stations had started "roadcasting on itG there 2ere many AM 3MW4stations in use for the purpose' *o later than the end of #$, the national pu"lic ser-ice"roadcasting company E(R6 3later also kno2n as ER64 placed in ser-ice its first FMtransmitter in the capital, Athens' By the end of the &s, most of @reek territory 2as co-ered

"y three *ational FM programs, and e-ery city had many FM 7pirates7 as 2ell' 6headaptation of the FM "and for pri-ately o2ned commercial radio stations came far later, in#$%'

#ustralia8edit9

FM started inAustraliain #$; "ut did not catch on and 2as shut do2n in #$># to eDpandthe tele-ision"and' (t 2as not reopened until #$!' Su"se/uently, it de-eloped steadily untilin the #$%&s many AM stations transferred to FM due to its superior sound /uality' 6oday, aselse2here in the de-eloped 2orld, most ur"an Australian "roadcasting is on FM, althoughAM talk stations are still -ery popular' Regional "roadcasters still commonly operate AMstations due to the additional range the "roadcasting method offers' Some stations in maIorregional centres simulcast on AM and FM "ands' ?igital radio using the ?ABJ standard has

"een rolled out to maIor cities'

$e% &ealand8edit9

+ike Australia, *e2 ealand adopted the FM format relati-ely late' As 2as the case 2ithpri-ately o2ned AM radio in the late #$>&s, it took a spate of OpirateO "roadcasters topersuade a control5oriented, technology a-erse go-ernment to allo2 FM to "e introducedafter at least fi-e years of consumer campaigning starting in the mid5#$&s, particularly inAuckland' An eDperimental FM station, FM $&', 2as "roadcast inWhakatanein early #$%'+ater that year, ictoria .ni-ersity of WellingtonOsRadio Acti-e"egan full5time FMtransmissions' Commercial FM licences 2ere finally appro-ed in #$%, 2ith Auckland5"ased $#FMand %$FM"eing the first to take up the offer'8#9' Broadcasting 2as deregulatedin #$%$'

'ur(ey8edit9

(n 6urkey, FM "roadcasting "egan in the late #$>&s, carrying se-eral sho2s from the =netele-ision net2ork 2hich 2as transferred from the AM fre/uency 3also kno2n as MW in6urkey4' (n su"se/uent years, more MW stations 2ere slo2ly transferred to FM, and "y theend of the #$&s, most radio stations that 2ere pre-iously on MW had "een mo-ed to FM,though many talk, ne2s and sport, "ut mostly religious stations, still remain on MW'

Other countries8edit9

Most other countries implemented FM "roadcasting through #$>&s and eDpanded their useof FM through the #$$&s' Because it takes a large num"er of FM transmitting stations toco-er a geographically large country, particularly 2here there are terrain difficulties, FM is

more suited to local "roadcasting than for national net2orks' (n such countries, particularly2here there are economic or infrastructural pro"lems, 7rolling out7 a national FM "roadcastnet2ork to reach the maIority of the population can "e a slo2 and eDpensi-e process'?espite this, mostly in east European counties, national FM "roadcast net2orks 2ereesta"lished in the late #$>&s and #$&s' (n all So-iet5dependent countries "ut @?R, the=(R6 "and 2as used' First restricted to >%5M01, in #$&s e-entually eDpanded to >!5;M01'

!'U Con)erences about FM8edit9

6he fre/uencies a-aila"le for FM 2ere decided "y some important conferences of(6.' 6hemilestone of those conferences is the Stockholm agreement of #$># among % countries'8#&9A #$%; conference in @ene-a made some modifications to the original Stockholm

agreement particularly in the fre/uency range a"o-e #&& M01'
https://en.wikipedia.org/wiki/Greecehttps://en.wikipedia.org/w/index.php?title=FM_broadcasting&action=edit&section=16https://en.wikipedia.org/wiki/Australiahttps://en.wikipedia.org/wiki/Australiahttps://en.wikipedia.org/wiki/Australiahttps://en.wikipedia.org/wiki/Televisionhttps://en.wikipedia.org/w/index.php?title=FM_broadcasting&action=edit&section=17https://en.wikipedia.org/wiki/FM_90.7_(New_Zealand)https://en.wikipedia.org/wiki/Whakatanehttps://en.wikipedia.org/wiki/Whakatanehttps://en.wikipedia.org/wiki/Victoria_University_of_Wellingtonhttps://en.wikipedia.org/wiki/Victoria_University_of_Wellingtonhttps://en.wikipedia.org/wiki/Radio_Active_(New_Zealand)https://en.wikipedia.org/wiki/Radio_Active_(New_Zealand)https://en.wikipedia.org/wiki/Magic_91FMhttps://en.wikipedia.org/wiki/89FM_(Auckland)http://www.oldradio.com/archives/international/nzp.htmlhttp://www.oldradio.com/archives/international/nzp.htmlhttps://en.wikipedia.org/w/index.php?title=FM_broadcasting&action=edit&section=18https://en.wikipedia.org/w/index.php?title=FM_broadcasting&action=edit&section=18https://en.wikipedia.org/wiki/Turkeyhttps://en.wikipedia.org/w/index.php?title=FM_broadcasting&action=edit&section=19https://en.wikipedia.org/w/index.php?title=FM_broadcasting&action=edit&section=20https://en.wikipedia.org/wiki/ITUhttps://en.wikipedia.org/wiki/ITUhttps://en.wikipedia.org/wiki/FM_broadcasting#cite_note-10https://en.wikipedia.org/wiki/FM_broadcasting#cite_note-10https://en.wikipedia.org/wiki/Greecehttps://en.wikipedia.org/w/index.php?title=FM_broadcasting&action=edit&section=16https://en.wikipedia.org/wiki/Australiahttps://en.wikipedia.org/wiki/Televisionhttps://en.wikipedia.org/w/index.php?title=FM_broadcasting&action=edit&section=17https://en.wikipedia.org/wiki/FM_90.7_(New_Zealand)https://en.wikipedia.org/wiki/Whakatanehttps://en.wikipedia.org/wiki/Victoria_University_of_Wellingtonhttps://en.wikipedia.org/wiki/Radio_Active_(New_Zealand)https://en.wikipedia.org/wiki/Magic_91FMhttps://en.wikipedia.org/wiki/89FM_(Auckland)http://www.oldradio.com/archives/international/nzp.htmlhttps://en.wikipedia.org/w/index.php?title=FM_broadcasting&action=edit&section=18https://en.wikipedia.org/wiki/Turkeyhttps://en.wikipedia.org/w/index.php?title=FM_broadcasting&action=edit&section=19https://en.wikipedia.org/w/index.php?title=FM_broadcasting&action=edit&section=20https://en.wikipedia.org/wiki/ITUhttps://en.wikipedia.org/wiki/FM_broadcasting#cite_note-10


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Small-scale use of the FM broadcast band8edit9

BelkinTuneCast II FM microtransmitter

Consumer use o) FM transmitters8edit9

(n some countries, small5scale 3Part #!in .nited States terms4 transmitters are a-aila"le thatcan transmit a signal from an audio de-ice 3usually an MP playeror similar4 to a standard

FM radio recei-erG such de-ices range from small units "uilt to carry audio to a car radio 2ithno audio5in capa"ility 3often formerly pro-ided "y special adapters for audio cassettedecks,2hich are "ecoming less common on car radio designs4 up to full5si1ed, near5professional5grade "roadcasting systems that can "e used to transmit audio throughout a property' Mostsuch units transmit in full stereo, though some models designed for "eginner ho""yists mightnot' Similar transmitters are often included in satellite radiorecei-ers and some toys'

+egality of these de-ices -aries "y country' 6he.'S' Federal CommunicationsCommissionand(ndustry Canadaallo2 them' Starting on # =cto"er &&>, these de-ices"ecame legal in most countries in theEuropean .nion'?e-ices made to the harmonisedEuropean specification "ecame legal in the.)on % ?ecem"er &&>'8##9

6he FM "roadcast "and is also used "y some ineDpensi-e 2ireless microphonessold as

toys forkaraokeor similar purposes, allo2ing the user to use an FM radio as an outputrather than a dedicated amplifier and speaker' Professional5grade 2ireless microphonesgenerally use "ands in the .0Fregion so they can run on dedicated e/uipment 2ithout"roadcast interference'

Some 2irelessheadphonestransmit in the FM "roadcast "and, 2ith the headphones tuna"leto only a su"set of the "roadcast "and' 0igher5/uality 2ireless headphones useinfraredtransmissionor .0F (SM "andssuch as #!M01, $#!Mh1, or ';@01 instead of the FM"roadcast "and'

Microbroadcasting8edit9

+o25po2er transmitters such as those mentioned a"o-e are also sometimes used forneigh"orhood or campus radio stations, though campus radio stations are often run

o-ercarrier current' 6his is generally considered a form of micro"roadcasting' As a generalrule8vague9, enforcement to2ards lo25po2er FM stations is stricter than AM stations due topro"lems such as the capture effect8citation needed9, and as a result, FM micro"roadcastersgenerally do not reach as far as their AM competitors'

Clandestine use o) FM transmitters8edit9

FM transmitters ha-e "een used to construct miniature 2ireless microphonesforespionageand sur-eillancepurposes 3co-ert listening de-icesor so5called 7"ugs74G thead-antage to using the FM "roadcast "and for such operations is that the recei-inge/uipment 2ould not "e considered particularly suspect' Common practice is to tune the"ugOs transmitter off the ends of the "roadcast "and, into 2hat in the .nited States 2ould "e6 channel > 3T%'$ M014 or a-iation na-igation fre/uencies 3U#&'$ M014G most FM radios

2ith analog tuners ha-e sufficient o-erco-erage to pick up these slightly5"eyond5outermostfre/uencies, although many digitally tuned radios ha-e not'
https://en.wikipedia.org/w/index.php?title=FM_broadcasting&action=edit&section=21https://en.wikipedia.org/wiki/Belkinhttps://en.wikipedia.org/w/index.php?title=FM_broadcasting&action=edit&section=22https://en.wikipedia.org/wiki/Part_15_(FCC_rules)https://en.wikipedia.org/wiki/MP3_playerhttps://en.wikipedia.org/wiki/MP3_playerhttps://en.wikipedia.org/wiki/Audio_cassettehttps://en.wikipedia.org/wiki/Satellite_radiohttps://en.wikipedia.org/wiki/Federal_Communications_Commissionhttps://en.wikipedia.org/wiki/Federal_Communications_Commissionhttps://en.wikipedia.org/wiki/Federal_Communications_Commissionhttps://en.wikipedia.org/wiki/Industry_Canadahttps://en.wikipedia.org/wiki/Industry_Canadahttps://en.wikipedia.org/wiki/European_Unionhttps://en.wikipedia.org/wiki/European_Unionhttps://en.wikipedia.org/wiki/European_Unionhttps://en.wikipedia.org/wiki/United_Kingdomhttps://en.wikipedia.org/wiki/United_Kingdomhttps://en.wikipedia.org/wiki/FM_broadcasting#cite_note-11https://en.wikipedia.org/wiki/Microphonehttps://en.wikipedia.org/wiki/Karaokehttps://en.wikipedia.org/wiki/Karaokehttps://en.wikipedia.org/wiki/Ultra_high_frequencyhttps://en.wikipedia.org/wiki/Ultra_high_frequencyhttps://en.wikipedia.org/wiki/Headphonehttps://en.wikipedia.org/wiki/Headphonehttps://en.wikipedia.org/wiki/Headphonehttps://en.wikipedia.org/wiki/Consumer_IRhttps://en.wikipedia.org/wiki/Consumer_IRhttps://en.wikipedia.org/wiki/ISM_bandhttps://en.wikipedia.org/w/index.php?title=FM_broadcasting&action=edit&section=23https://en.wikipedia.org/wiki/Carrier_currenthttps://en.wikipedia.org/wiki/Microbroadcastinghttps://en.wikipedia.org/wiki/Wikipedia:Vaguenesshttps://en.wikipedia.org/wiki/Wikipedia:Vaguenesshttps://en.wikipedia.org/wiki/Wikipedia:Vaguenesshttps://en.wikipedia.org/wiki/Capture_effecthttps://en.wikipedia.org/wiki/Capture_effecthttps://en.wikipedia.org/wiki/Wikipedia:Citation_neededhttps://en.wikipedia.org/wiki/Wikipedia:Citation_neededhttps://en.wikipedia.org/w/index.php?title=FM_broadcasting&action=edit&section=24https://en.wikipedia.org/wiki/Espionagehttps://en.wikipedia.org/wiki/Espionagehttps://en.wikipedia.org/wiki/Surveillancehttps://en.wikipedia.org/wiki/Covert_listening_devicehttps://en.wikipedia.org/w/index.php?title=FM_broadcasting&action=edit&section=21https://en.wikipedia.org/wiki/Belkinhttps://en.wikipedia.org/w/index.php?title=FM_broadcasting&action=edit&section=22https://en.wikipedia.org/wiki/Part_15_(FCC_rules)https://en.wikipedia.org/wiki/MP3_playerhttps://en.wikipedia.org/wiki/Audio_cassettehttps://en.wikipedia.org/wiki/Satellite_radiohttps://en.wikipedia.org/wiki/Federal_Communications_Commissionhttps://en.wikipedia.org/wiki/Federal_Communications_Commissionhttps://en.wikipedia.org/wiki/Industry_Canadahttps://en.wikipedia.org/wiki/European_Unionhttps://en.wikipedia.org/wiki/United_Kingdomhttps://en.wikipedia.org/wiki/FM_broadcasting#cite_note-11https://en.wikipedia.org/wiki/Microphonehttps://en.wikipedia.org/wiki/Karaokehttps://en.wikipedia.org/wiki/Ultra_high_frequencyhttps://en.wikipedia.org/wiki/Headphonehttps://en.wikipedia.org/wiki/Consumer_IRhttps://en.wikipedia.org/wiki/Consumer_IRhttps://en.wikipedia.org/wiki/ISM_bandhttps://en.wikipedia.org/w/index.php?title=FM_broadcasting&action=edit&section=23https://en.wikipedia.org/wiki/Carrier_currenthttps://en.wikipedia.org/wiki/Microbroadcastinghttps://en.wikipedia.org/wiki/Wikipedia:Vaguenesshttps://en.wikipedia.org/wiki/Capture_effecthttps://en.wikipedia.org/wiki/Wikipedia:Citation_neededhttps://en.wikipedia.org/w/index.php?title=FM_broadcasting&action=edit&section=24https://en.wikipedia.org/wiki/Espionagehttps://en.wikipedia.org/wiki/Surveillancehttps://en.wikipedia.org/wiki/Covert_listening_device


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Constructing a 7"ug7 is a common early proIect for electronics ho""yists, and proIect kits todo so are a-aila"le from a 2ide -ariety of sources' 6he de-ices constructed, ho2e-er, areoften too large and poorly shielded for use in clandestine acti-ity'

(n addition, much pirate radioacti-ity is "roadcast in the FM range, "ecause of the "andOsgreater clarity and listenership, the smaller si1e and lo2er cost of e/uipment'

See also8edit9FM broadcasting by country8edit9

FM "roadcasting in Australia

FM "roadcasting in Canada

FM "roadcasting in Egypt

FM "roadcasting in (ndia

FM "roadcasting in apan

FM "roadcasting in *e2 ealand

FM "roadcasting in Pakistan

FM "roadcasting in the .)

FM "roadcasting in the .nited States

FM broadcasting *technical+8edit9

AM "roadcasting

AM stereo3related technology4

FM "roadcast "and

FM stereo

Fre/uency modulation

+ong5distance FM reception 3FM ?4

Ripping music from FM "roadcasts

R?S 3Radio ?ata System4

,ists8edit9

+ist of "roadcast station classes

+ists of radio stations in *orth America

istory8edit9
https://en.wikipedia.org/wiki/Pirate_radiohttps://en.wikipedia.org/w/index.php?title=FM_broadcasting&action=edit&section=25https://en.wikipedia.org/w/index.php?title=FM_broadcasting&action=edit&section=26https://en.wikipedia.org/wiki/FM_broadcasting_in_Australiahttps://en.wikipedia.org/wiki/FM_broadcasting_in_Canadahttps://en.wikipedia.org/wiki/FM_broadcasting_in_Egypthttps://en.wikipedia.org/wiki/FM_broadcasting_in_Indiahttps://en.wikipedia.org/wiki/FM_broadcasting_in_Japanhttps://en.wikipedia.org/wiki/FM_broadcasting_in_New_Zealandhttps://en.wikipedia.org/wiki/FM_broadcasting_in_Pakistanhttps://en.wikipedia.org/wiki/FM_broadcasting_in_the_UKhttps://en.wikipedia.org/wiki/FM_broadcasting_in_the_United_Stateshttps://en.wikipedia.org/w/index.php?title=FM_broadcasting&action=edit&section=27https://en.wikipedia.org/wiki/AM_broadcastinghttps://en.wikipedia.org/wiki/AM_stereohttps://en.wikipedia.org/wiki/FM_broadcast_bandhttps://en.wikipedia.org/wiki/FM_stereohttps://en.wikipedia.org/wiki/Frequency_modulationhttps://en.wikipedia.org/wiki/TV_and_FM_DXhttps://en.wikipedia.org/wiki/Radio_music_rippinghttps://en.wikipedia.org/wiki/Radio_Data_Systemhttps://en.wikipedia.org/w/index.php?title=FM_broadcasting&action=edit&section=28https://en.wikipedia.org/wiki/List_of_broadcast_station_classeshttps://en.wikipedia.org/wiki/Lists_of_radio_stations_in_North_Americahttps://en.wikipedia.org/w/index.php?title=FM_broadcasting&action=edit&section=29https://en.wikipedia.org/w/index.php?title=FM_broadcasting&action=edit&section=29https://en.wikipedia.org/wiki/Pirate_radiohttps://en.wikipedia.org/w/index.php?title=FM_broadcasting&action=edit&section=25https://en.wikipedia.org/w/index.php?title=FM_broadcasting&action=edit&section=26https://en.wikipedia.org/wiki/FM_broadcasting_in_Australiahttps://en.wikipedia.org/wiki/FM_broadcasting_in_Canadahttps://en.wikipedia.org/wiki/FM_broadcasting_in_Egypthttps://en.wikipedia.org/wiki/FM_broadcasting_in_Indiahttps://en.wikipedia.org/wiki/FM_broadcasting_in_Japanhttps://en.wikipedia.org/wiki/FM_broadcasting_in_New_Zealandhttps://en.wikipedia.org/wiki/FM_broadcasting_in_Pakistanhttps://en.wikipedia.org/wiki/FM_broadcasting_in_the_UKhttps://en.wikipedia.org/wiki/FM_broadcasting_in_the_United_Stateshttps://en.wikipedia.org/w/index.php?title=FM_broadcasting&action=edit&section=27https://en.wikipedia.org/wiki/AM_broadcastinghttps://en.wikipedia.org/wiki/AM_stereohttps://en.wikipedia.org/wiki/FM_broadcast_bandhttps://en.wikipedia.org/wiki/FM_stereohttps://en.wikipedia.org/wiki/Frequency_modulationhttps://en.wikipedia.org/wiki/TV_and_FM_DXhttps://en.wikipedia.org/wiki/Radio_music_rippinghttps://en.wikipedia.org/wiki/Radio_Data_Systemhttps://en.wikipedia.org/w/index.php?title=FM_broadcasting&action=edit&section=28https://en.wikipedia.org/wiki/List_of_broadcast_station_classeshttps://en.wikipedia.org/wiki/Lists_of_radio_stations_in_North_Americahttps://en.wikipedia.org/w/index.php?title=FM_broadcasting&action=edit&section=29


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0istory of radio

=ldest radio station
https://en.wikipedia.org/wiki/History_of_radiohttps://en.wikipedia.org/wiki/Oldest_radio_stationhttps://en.wikipedia.org/wiki/History_of_radiohttps://en.wikipedia.org/wiki/Oldest_radio_station

Documents

FM broadcasting.docx