Editing AM broadcasting (section)

===Decline in popularity===

In the 1940s two new broadcast media, [[FM broadcasting|FM radio]] and [[television]], began to provide extensive competition with the established broadcasting services. The AM radio industry suffered a serious loss of audience and advertising revenue, and coped by developing new strategies. Network broadcasting gave way to [[radio format|format]] broadcasting: instead of broadcasting the same programs all over the country, stations individually adopted specialized formats which appealed to different audiences, such as regional and local news, sports, "talk" programs, and programs targeted at minorities. Instead of live music, most stations began playing less expensive recorded music.

In the late 1960s and 1970s, top 40 rock and roll stations in the U.S. and Canada such as [[WABC (AM)|WABC]] and [[CHUM (AM)|CHUM]] transmitted highly processed and extended audio to 11 kHz, successfully attracting huge audiences.  For young people, listening to AM broadcasts and participating in their music surveys and contests was the social media of the time.

In the late 1970s, spurred by the exodus of musical programming to FM stations, the AM radio industry in the United States developed technology for broadcasting in [[stereophonic sound|stereo]]. Other nations adopted AM stereo, most commonly choosing Motorola's C-QUAM, and in 1993 the United States also made the C-QUAM system its standard, after a period allowing four different standards to compete. The selection of a single standard improved acceptance of [[AM stereo]],<ref name="stereo">[https://www.fcc.gov/media/radio/am-stereo-broadcasting "AM Stereo Broadcasting"] (fcc.gov)</ref> however overall there was limited adoption of AM stereo worldwide, and interest declined after 1990. With the continued migration of AM stations away from music to news, sports, and talk formats, receiver manufacturers saw little reason to adopt the more expensive stereo tuners, and thus radio stations have little incentive to upgrade to stereo transmission.

In countries where the use of directional antennas is common, such as the United States, transmitter sites consisting of multiple towers often occupy large tracts of land that have significantly increased in value over the decades, to the point that the value of land exceeds that of the station itself. This sometimes results in the sale of the transmitter site, with the station relocating to a more distant shared site using significantly less power,<ref>[https://www.post-gazette.com/ae/tv-radio/2019/12/24/KQV-Pittsburgh-back-on-air-easy-listening-format/stories/201912240090 "Radio fans' holiday joy: KQV is back on the air"] by Maria Sciullo, ''Pittsburgh Post-Gazette'', December 24, 2019.</ref> or completely shutting down operations.<ref>[https://radioinsight.com/headlines/204891/1560-wfme-new-york-to-suspend-operations-friday/ "1560 WFME New York To Suspend Operations Friday"] by Lance Venta, February 11, 2021 (radioinsight.com).</ref>

The ongoing development of alternative transmission systems, including Digital Audio Broadcasting (DAB), satellite radio, and HD (digital) radio, continued the decline of the popularity of the traditional broadcast technologies. These new options, including the introduction of Internet streaming, particularly resulted in the reduction of shortwave transmissions, as international broadcasters found ways to reach their audiences more easily.<ref>[https://www.radioworld.com/news-and-business/whatever-happened-to-shortwave-radio/302129 "Whatever Happened to Shortwave Radio?"] by James Careless, March 8, 2010 (radioworld.com).</ref>

In 2022 it was reported that AM radio was being removed from a number of [[electric vehicle]] (EV) models, including from cars manufactured by Tesla, Audi, Porsche, BMW and Volvo, reportedly due to automakers concerns that an EV's higher electromagnetic interference can disrupt the reception of AM transmissions and hurt the listening experience, among other reasons.<ref>{{Cite news |last=Levenson |first=Michael |date=2022-12-10 |title=In a Future Filled With Electric Cars, AM Radio May Be Left Behind |language=en-US |work=The New York Times |url=https://www.nytimes.com/2022/12/10/business/media/am-radio-cars.html |access-date=2022-12-29 |issn=0362-4331}}</ref><ref>{{Cite web |last=Gilboy |first=James |date=2022-07-06 |title=Automakers Are Starting to Drop AM Radio in New Cars. Here's Why |url=https://www.thedrive.com/news/heres-why-some-automakers-tune-out-am-radios-in-new-cars |access-date=2022-12-29 |website=The Drive |language=en}}</ref> However the United States Congress has introduced a bill to require all vehicles sold in the US to have an AM receiver to receive emergency broadcasts.<ref>{{cite news |last1=Gitlin |first1=Jonathan M. |title=Congress wants AM radio in all new cars—trade groups say that's a mistake |url=https://arstechnica.com/cars/2023/05/ev-advocates-join-tech-groups-and-automakers-to-oppose-am-radio-mandate/ |access-date=23 May 2023 |work=Ars Technica |date=23 May 2023 |language=en-us}}</ref>