KCBS (740 kHz) is an all-news AM radio station located in San Francisco, California. It is owned by Audacy, Inc. (formerly Entercom), which took over after its merger with CBS Radio.
KCBS formerly shared its Battery Street studios with CBS owned-and-operated television station KPIX-TV 5. The transmitter site is located in Novato. Its programming is simulcast on co-owned 106.9 KFRC-FM plus that station's HD1 digital sub-channel."HD Radio Guide: San Francisco, California" (hdradio.com) It is Northern California's primary entry point station for the Emergency Alert System.
KCBS operates with a transmitter output of 50,000 watts, and during the daytime can be regularly received as far north as Red Bluff and Hopland and south as far as San Luis Obispo. In good conditions it is also heard as far north as Redding and south to Santa Maria. At night, the station employs a directional antenna, primarily sending its signal to the southeast, in order to protect CFZM in Toronto, the dominant Class A station on the 740 kHz clear-channel frequency. Even with this restriction, KCBS's nighttime signal reaches a large slice of the Western United States with a good radio. This includes almost all of California, as far south as Los Angeles and San Diego. On rare occasions "DXers" (hobbyists who listen for distant stations) have reported receiving KCBS across the Pacific Ocean, and in Hawaii and Alaska.Mariners have also reported hearing KCBS on Marine VHF radio channel 22 on incorrectly configured receivers: "Getting AM radio stations on VHF Radio" (forum thread), June 25, 2010 (sailnet.com)
In addition to over-the-air broadcasts, KCBS audio is webcast with live streaming audio around the clock. The station's live stream is available through the Audacy app along with TuneIn and iHeartRadio as of 2025; in October 2019, it was one of the test stations for the Audacy (then known as Radio.com) app's new "Rewind" feature, where the last 24 hours of KCBS programming can be accessed on-demand.
Programming Like most of its sister Audacy all-news stations, KCBS airs hourly ABC News Radio reports. Additional features include traffic, weather, sports updates, and "Bloomberg Moneywatch" business reports. KPIX-TV meteorologists provide weather forecasts, especially during AM and PM drive times.
The station hosts special segments each weekday with San Francisco Chronicle columnist Phil Matier and others. KCBS will often feature live interviews with call-in guest experts (who occasionally also appear in the studio with the anchors) to briefly discuss a specific story, topic or subject; the edited comments are replayed as part of featured news stories throughout the remainder of the day.
Beginning in December 2025, KCBS programming is simulcast on sister all-news station KNX (AM) in Los Angeles. between midnight and 5 am. News, traffic, and weather reports during the overnight hours include both Bay Area and Los Angeles stories.
History Experimental years
KCBS is considered to be among the world's first radio stations. It received its first broadcasting station license, as KQW in San Jose, in early December 1921. However, the original licensee, Charles Herrold, had begun making audio radio transmissions in 1909, as part of an experimental radio-telephone system, and KCBS has traditionally dated its founding to that year. Herrold's earliest radio work had been largely forgotten until 1959, when Gordon R. Greb's "The Golden Anniversary of Broadcasting" was published in the Journal of Broadcasting."The Golden Anniversary of Broadcasting" by Gordon R. Greb, Journal of Broadcasting, Winter 1958-1959, pages 3-13.
On January 1, 1909, Herrold opened the Herrold College of Wireless and Engineering, located in the Garden City Bank Building at 50 West San Fernando Street in San Jose. In order to promote the college, as well as provide practical experience for his students, a radio transmitter (then commonly known as "wireless telegraphy") with a large antenna was constructed atop the building. The earliest transmissions used spark-gap transmitters which could only transmit the dots-and-dashes of Morse code.
Herrold was among the first to develop a radio transmitter that could also be used for audio transmissions. After limited success with an approach that used "high-frequency" sparks, he later began using a version of an "arc-transmitter" originally developed by Valdemar Poulsen.Charles Herrold, Inventor of Radio Broadcasting by Gordon Greb and Mike Adams, 2003, pages 82–84. Although his primary objective was to create a wireless telephone that could be commercialized for point-to-point use, beginning in July 1912 Herrold also began making regular weekly entertainment broadcasts, with the debut program featuring phonograph records supplied by the Wiley B. Allen company."Will Give Concert by Wireless Telephone", San Jose Mercury Herald, July 21, 1912, page 27. A wire service report reviewed a July 22, 1912 broadcast:
Radio communication was initially unregulated in the United States, and at first Herrold used a variety of self-assigned identifiers for his station, including FN"FN" was the inverted initials of "National Fone". and SJN, plus, for audio transmissions, "San Jose calling". The Radio Act of 1912 established the licensing of stations through the U.S. Commerce Department, and in late 1915 Herrold was issued an Experimental Station License with the call sign 6XF."Special Land Stations", Radio Service Bulletin, December 1915, page 2. Although Herrold reported success in developing his system, his arc-transmitters were low-powered and would only work at wavelengths above 600 meters (frequencies below 500 kHz).Wireless Communications in the United States by Thorn L. Mayes, 1989, page 206. The concurrent development of vacuum-tube technology, which did not have the same limitations, started making arc technology obsolete.
World War I In April 1917, with the entrance of the United States into World War I, the U.S. government took control of the entire radio industry, and it became illegal for private citizens to possess a working radio receiver. In addition, all civilian radio stations were ordered to be dismantled, so for the duration of the conflict Herrold left the airwaves. This wartime government ban on civilian stations was lifted effective October 1, 1919, and in early 1921 Herrold was reissued an Experimental license, again with the call sign 6XF."Special Land Stations", Radio Service Bulletin, April 1, 1921, page 4. (He had previously been issued a license for a portable transmitter, with the call sign 6XE.)"Special Land Stations", Radio Service Bulletin, October 1, 1920, page 5.
During the war impressive strides had been made in vacuum-tube transmitter and receiver design, and Herrold's arc-transmitters were no longer commercially competitive. In 1920 a number of radio stations in the San Francisco Bay area, employing vacuum-tube transmitters, began making regular entertainment broadcasts, most prominently the "California Theater" station, 6XC, set up by Lee de Forest, which began daily service around April 1920."Radio Telephone Development in the West" by Harry Lubcke, Radio News, February 1922, page 702. After the war Herrold needed to become familiar with vacuum-tube equipment before he could return to the air. Although some of his co-workers later reported that he resumed regular broadcasts as early as 1919, the oldest documented report of his resumption of broadcasting, presumably over 6XF, dates to early May 1921, with the announcement that the school was inaugurating a Monday and Thursday night schedule consisting of records supplied by "J. A. Kerwin of 84 East Santa Clara street, dealer in phonographs"."Radio School Sends Jazz Music via Air", San Jose Mercury Herald, May 3, 1921, page 4.
KQW (1921–1949)
Effective December 1, 1921, the Department of Commerce issued a regulation that stations making broadcasts intended for the general public now had to hold a Limited Commercial license specifying operation on a wavelength of 360 or 485 meters,"Amendments to Regulations", Radio Service Bulletin, January 3, 1922, page 10. and, on December 9, 1921, a broadcasting station authorization with the randomly assigned call letters of KQW was issued in Herrold's name.Limited Commercial license, serial #255, issued on December 8, 1921, for one year. This license specified operation on the common "entertainment" wavelength of 360 meters (833 kHz), so KQW initially broadcast only during the hours assigned to it under a time-sharing agreement made with the other local broadcasting stations.
Classifying stations according to when they first received a broadcasting authorization under the provisions of the December 1, 1921, regulations, KQW was tied for 6th in the state of California and 16th in the United States. It is the eighth oldest surviving radio station in the United States and tied for 2nd oldest in California, one day behind KWG in Stockton,Limited Commercial license, serial #245, issued on December 7, 1921, for one year to the Portable Wireless Telephone Company. and tied with KNX in Los Angeles.Limited Commercial license, serial #248, issued on December 8, 1921, for one year (as KGC) to the Electric Lighting Supply Company. It is also the oldest in the Bay Area; the next-oldest, KMKY in Oakland, was licensed as KLS on March 10, 1922.
Operation of KQW was financed by the sale of radio equipment by the Herrold Radio Laboratory, but by 1925 the costs had grown. The station was transferred to the First Baptist Church of San Jose, with Herrold kept on as program director. In 1926, station manager Fred J. Hart bought KQW's license and facilities, eventually buying the station itself in 1930. From 1937 to 1941, KQW served as the San Jose network affiliate of the Don Lee Broadcasting System. During this time its owner was Julius Brunton & Sons, and the station's operations were co-located with KJBS at 1470 Pine Street in San Francisco. Until 1942, it operated as a service of the Pacific Agricultural Foundation to farmers in the Central Valley.
In 1927, the Federal Radio Commission (FRC) was created to take over the regulation of U.S. radio stations, and it began a series of frequency shifts to coordinate station assignments. Effective November 11, 1928, the FRC divided the AM band transmitting frequencies into three classification: Local, Regional, and Clear Channel. KQW's assignment, 1010 kHz, which it had been using since the previous year, was designated a regional frequency."Broadcasting Stations Alphabetically by States and Cities: Effective June 15, 1927", Radio Service Bulletin, May 31, 1927, page 5. By 1940, KQW had increased its daytime power to the maximum permitted for regional stations, 5,000 watts. In March 1941, under the provisions of the North American Regional Broadcasting Agreement (NARBA), most U.S. radio stations were shifted to new dial positions, so KQW moved to 740."Your Radio Stations Have New Homes", San Francisco Chronicle, March 29, 1941, page 7.