Editing AM broadcasting (section)

{{Short description|Radio broadcasting using amplitude modulation}}
{{Redirect|AM radio|the song by Everclear|AM Radio (song)|the American musical group|AM Radio (band)}}
{{Infobox technology standard
| title             = AM broadcasting
| long_name         = [[Amplitude modulation]]
| image             = Amfm3-en-de.gif
| image_size        = 
| alt               = 
| caption           = AM and FM modulated signals for radio. [[amplitude modulation]] (AM) and [[frequency modulation]] (FM) are types of [[modulation]] (coding). The electrical signal from program material, usually coming from a [[radio studio|studio]], is mixed with a [[carrier wave]] of a specific frequency, then broadcast. In the case of AM, this mixing (modulation) is done by altering the [[amplitude]] (strength) of the carrier wave, proportional to the original signal. In contrast, in the case of FM, it is the carrier wave's [[frequency]] that is varied. A radio receiver contains a demodulator that [[Demodulation|extracts]] the original program material from the broadcast wave.
| abbreviation      = AM
| native_name       = <!-- Name in local language. If more than one, separate using {{plain list}} -->
| native_name_lang  = <!-- ISO 639-1 code e.g. "fr" for French. If more than one, use {{lang}} inside native_name items instead -->
| status            = Active
| year_started      = {{Start date and age|1901|df=y}}
| first_published   = <!-- {{Start date|YYYY|MM|DD|df=y}} -->
| version           = 
| version_date      = 
| preview           = 
| preview_date      = 
| organization      = 
| committee         = 
| series            = 
| editors           = 
| authors           = [[Reginald Fessenden]]
| base_standards    = 
| related_standards = 
| predecessor       = 
| successor         = 
| domain            = 
| license           = Public
| copyright         = 
| website           = {{URL| https://www.fcc.gov/general/am-radio}}
}}

'''AM broadcasting''' is [[radio broadcasting]] using [[amplitude modulation]] (AM) transmissions. It was the first method developed for making audio radio transmissions, and is still used worldwide, primarily for [[medium wave]] (also known as "AM band") transmissions, but also on the [[longwave]] and [[shortwave radio]] bands.
 
The earliest experimental AM transmissions began in the early 1900s. However, widespread AM broadcasting was not established until the 1920s, following the development of [[vacuum tube]] receivers and transmitters. AM radio remained the dominant method of broadcasting for the next 30 years, a period called the "[[Golden Age of Radio]]", until [[television broadcasting]] became widespread in the 1950s and received much of the programming previously carried by radio. Later, AM radio's audiences declined greatly due to competition from FM ([[FM broadcasting|frequency modulation]]) radio, [[Digital audio broadcasting|Digital Audio Broadcasting]] (DAB), [[satellite radio]], [[HD Radio|HD (digital) radio]], [[Internet radio]], [[music streaming service]]s, and [[podcasting]].

Compared to FM or [[Digital transmission|digital transmissions]], AM transmissions are more expensive to transmit due to the necessity of having to transmit a high power carrier wave to overcome ground losses, and the large antenna radiators required at the low broadcast frequencies, but can be sent over long distances via the ionosphere at night; however, they are much more susceptible to interference, and often have lower audio fidelity.<ref>{{Cite web |date=<!-- 9:40 AM EST --> November 6, 2017 |title=VERIFY: Why Does AM Radio Sound Worse Than FM? |url=https://www.wfmynews2.com/article/news/verify/verify-why-does-am-radio-sound-worse-than-fm/83-489480515 |access-date=2022-12-29 |website=wfmynews2.com |language=en-US}}</ref><ref>{{Cite web |title=A Science Odyssey: Radio Transmission: FM vs AM |url=https://www.pbs.org/wgbh/aso/tryit/radio/radiorelayer.html |access-date=December 29, 2022 |website=pbs.org}}</ref> Thus, AM broadcasters tend to specialize in spoken-word formats, such as [[talk radio]], [[all-news radio]] and [[sports radio]], with music formats primarily for FM and digital stations.

[[File:DRM-Frequenzbereiche.png|thumb|Main radio bands]]