Origin Although KNX received its first broadcasting station license on December 8, 1921, the station has traditionally dated its founding to September 10, 1920, reflecting broadcasts conducted by Fred Christian over his amateur station, 6ADZ. Christian was a former shipboard radio operator, who lived at 5118 Harold Way in
Hollywood, California, and was the manager of the Electric Lighting Supply Company at 216 West Third Street, Los Angeles. He later explained that he began the broadcasts in order to provide something to listen to by customers who had constructed receivers from parts purchased at the store. Christian began making broadcasts with a five-watt vacuum-tube transmitter, operating on the standard amateur wavelength of 200 meters (1500
kHz).
KGC Initially there were no specific standards in the United States for radio stations making transmissions intended for the general public, and numerous stations under various classifications made entertainment broadcasts. However, effective December 1, 1921, the Department of Commerce, regulators of radio at this time, adopted a regulation that formally created a broadcasting station category, and stations were now required to hold a Limited Commercial license authorizing operation on wavelengths of 360 meters (833 kHz) for "entertainment" broadcasts or 485 meters (619 kHz) for "market and weather reports". By the end of 1922, over 500 stations were authorized nationwide. On December 8, 1921, the Electric Lighting Supply Company was issued a broadcasting station license with the randomly assigned call letters KGC, the second in the county after
KQL, authorizing operation on the 360-meter entertainment wavelength. The station's location was listed as Fred Christian's Harold Way home. The shared 360 meter wavelength required timesharing agreements between an increasing number of stations needing exclusive time periods. On May 4 the
Los Angeles Times reported that a total of seven local stations were slated to make broadcasts that day, comprising a schedule that ran from noon to 9 p.m., with KGC assigned 2-2:30 and 7:30-8 p.m.
KNX . On May 4, 1922, the Electric Lighting Supply Company was issued a broadcasting license for a station with the randomly assigned call letters of KNX, also on 360 meters, and located at the company's Los Angeles store on West Third Street. This was technically considered to be a second station in addition to KGC, however, after KGC was formally deleted on June 20, 1922, the Department of Commerce concluded that KGC and KNX were functionally the same station, and
Federal Communications Commission (FCC) records list KGC's initial license date, December 8, 1921, as KNX's "date first licensed". The new authorization coincided with preparations for a move to the California Theater, broadcasting live music, with Fred Christian continuing as station manager. On June 12, 1922, the
Los Angeles Times reported that "After more than two months of preparation, the new broadcast station at the California Theater had its opening program Saturday evening at 9:15, sending out a wavelength of 510 meters [588 kHz]. The station is said to be one of the best in the land, the call letters of which are KNX." KNX's regular broadcast schedule on 360 meters was 9:00 to 10:00 a.m. A week after it commenced operations from the theater, the
Times reported that "Numerous reports have come into The Times radio department commending the quality and audibility of material broadcast from KNX, the California Theater radiophone. This station differs from other stations in that it gives its listeners-in the music of the complete orchestra of the California Theater." KNX's power was raised to 100 watts in early August 1922.
Los Angeles Evening Express In the fall of 1924, Guy Earl Jr., owner of the
Los Angeles Evening Express, arranged for the newspaper's purchase of KNX. The
Express made significant upgrades, including increasing the power to 500 watts, and began broadcasting from the Paul G. Hoffman Studebaker building in Hollywood. KNX was one of the last stations to remain on the original 360 meter wavelength, and the newspaper engineered a move to 890 kHz. It remained on this frequency until November 11, 1928, when the station was reassigned to 1050 kHz, under the provisions of a major reallocation resulting from the
Federal Radio Commission's (FRC)
General Order 40. In early 1928, Guy Earle sold his share of the Evening Express newspaper and reorganized KNX as the Western Broadcast Company. The following year, KNX's transmitting power was raised to the nationwide maximum of 50,000 watts, which the station continues presently.
CBS ownership CBS purchased KNX in 1936, and began operating it as its West Coast
flagship, which ended CBS's eight-year
affiliation with
KHJ. In 1938, the
CBS Columbia Square studios were dedicated for KNX as well as West Coast operations for the entire CBS radio network. That October, the station carried
Orson Welles' celebrated version of
The War of the Worlds. In March 1941, the station was shifted to 1070 AM as part of the
North American Regional Broadcasting Agreement assignments, where it has been ever since. Theatre legend
Jerome Lawrence got his start in radio writing at KNX in the late 1930s. Legendary performers from the "
Golden Age of Radio" used KNX studios for their national broadcasts, included
Jack Benny,
Bing Crosby,
George Burns,
Edgar Bergen and
Gene Autry.
FM and TV stations On March 30, 1948, KNX added a
sister station. The original station with the
call sign KNX-FM
signed on the air, mostly simulcasting 1070 AM. At first it was on the old FM band, but switched to 93.1 a few years later. Today that station is
KCBS-FM, while a new version of KNX-FM exists today on 97.1 as a
simulcast of the AM station. In 1951, KNX gained a television cousin when CBS acquired KTSL channel 2 and rebranded it as KNXT. It took on the current
KCBS-TV call sign in 1984. It traces its history back to 1930s experimental broadcasts and was originally owned by broadcast pioneer
Don Lee.
Switch to all-news KNX was a strong competitor in the Los Angeles market while Bob Crane was its morning personality, but began declining in popularity after he left to star in the CBS television series ''
Hogan's Heroes''. Following the example of corporate sister station
WCBS in New York City, which had enjoyed success with an all-news format, KNX then became an all-news station in the spring of 1968. By chance, its first major breaking news coverage was a major worldwide story that happened locally: the
assassination of
Democratic Presidential candidate Robert F. Kennedy, in the
Ambassador Hotel in Los Angeles, on June 5 of that year. In August 2005, KNX moved out of Columbia Square after operating there for 67 years, and began broadcasting from new studios in the
Miracle Mile district on
Wilshire Boulevard. In 2009, KNX adopted the slogan "All news, all the time". It was previously used for 40 years by
KFWB, KNX's historic rival in the news radio wars before both became sister stations through the 1995 merger of
Westinghouse Electric (KFWB's owner) and CBS. KFWB's format change to
news/talk in September 2009, left KNX as the only all-news outlet in the Los Angeles area, which is now emphasized in its alternate slogan, "Southern California's only 24-hour local news & traffic station". In 2017, KNX won its first ever national Edward R. Murrow award for "Breaking News". The station was also nominated for two 2017 NAB Marconi awards, Legendary Station of the Year and News/Talk Station of the Year.
Entercom and Audacy On February 2, 2017, CBS agreed to merge CBS Radio with
Entercom, then the fourth-largest radio broadcaster in the United States. The sale was conducted tax-free using a
Reverse Morris Trust. While CBS shareholders retained a 72% ownership stake in the combined company, Entercom was the surviving entity, separating KNX from KCBS-TV and
KCAL-TV. The merger was approved on November 9, and was consummated 8 days later. On March 30, 2021, Entercom announced that the company changed its name to Audacy. On December 6, 2021, KNX announced that it would be adding an FM simulcast. KNX's all-news programming would also be heard on sister station KNOU, replacing the
Top 40 format on the station that began in 2009. KNOU changed its call letters to
KNX-FM on December 21, 2021, to match its AM simulcast partner. On December 9, 2025, KNX began simulcasting with sister all news station
KCBS (AM) between midnight and 5 am. News, traffic and weather reports are combined to cover both Los Angeles and the
San Francisco Bay Area and originate from KCBS in San Francisco. On April 28, 2026, Audacy announced it would be ending the FM simulcast of KNX on 97.1 FM on May 11 as it flips that station to a sports radio format as
97.1 The Fan; the station will continue to be heard on 1070 AM along with 97.1 FM’s HD2 subchannel and the Audacy app. ==Transmitter site==