Histopathology image classification: Highlighting the gap between manual analysis and AI automation

KDFC (90.3 FM; "Classical California KDFC") is a non-commercial radio station in San Francisco, California, that broadcasts classical music 24 hours daily. It is owned by the University of Southern California. KDFC is the radio home of the San Francisco Symphony and the San Francisco Opera. The station's live stream is available on the Internet and through the station's mobile app.

From 1963 until 2011, KUSF was a student-run broadcast station owned by the University of San Francisco.^[3] The station was located in the basement of Phelan Hall on the University of San Francisco campus, and was funded by the University of San Francisco, local and merchant underwriting, individual donations, and foundation grants.

KUSF began in 1963 as a campus-only AM station managed by the Associated Students of the University of San Francisco (ASUSF). In 1973, USF was offered KCMA, the FM radio station of Simpson Bible College, a small local Bible college that wished to discontinue its radio operations; KCMA had signed on in 1964.^[4] USF accepted the offer and on April 25, 1977, KUSF became an FM station broadcasting on the 90.3 frequency; the call letters had been changed over shortly after the university became the licensee, on August 20, 1973.^[3] The old AM station later became the student-managed KDNZ.

Originally broadcasting six hours a day, KUSF began broadcasting 24 hours a day in 1981. In its early days KUSF was a conventional college station, broadcasting programs of interest to the university and greater San Francisco community. However, KUSF soon garnered attention by playing new underground music: it was one of the first radio stations to play punk rock. Many now-famous acts also first gained exposure on KUSF, most notably The B-52s and Metallica.

KDFC was founded in 1948.^[5] Bill Crocker founded the station and was its first general manager. Sales were handled by Ed Davis, who later became the station's long-running general manager. Engineering was handled by Herbert Florance. The initials of their last names gave the radio station its call sign.^[1] It has programmed classical music for most of its history, though at one point during the 1950s, it featured a beautiful music format. ^{[citation needed]}

For many years the programming, which was largely automated after 1976, was simulcast on KIBE 1220 AM, a 5 kW AM station in Palo Alto, California that began broadcasting in 1949 from a transmitter near the western approach to the Dumbarton Bridge.^{[citation needed]}

Ed Davis's company Sundial Broadcasting sold the AM and FM to Brown Broadcasting in 1993 for US$15.5 million. In 1996, Brown Broadcasting sold the FM station and AM simulcast sister station (KDFC 1220 AM) to Evergreen Media, who in turn sold the FM to Bonneville Broadcasting and the AM to Douglas Broadcasting in 1997. New station management transitioned KDFC's programming to a more mass-appeal approach, which boosted ratings significantly, though was occasionally criticized for their new "top 40 of classical music" approach.

Bill Lueth, who had done mornings on rival classical station KKHI, moved to mornings at KDFC in 1997 and also contributed to the station's rise and shift from automation to live hosts.^{[citation needed]} In 2003 KDFC became the first station in the Bay Area to broadcast using HD Radio.^{[citation needed]}

On January 18, 2007, Bonneville signed an agreement with Entercom Communications Corporation to trade three San Francisco stations — KOIT, KMAX-FM, and KDFC — for three Entercom stations in Seattle, Washington and four in Cincinnati, Ohio. Entercom officially took ownership of KDFC in March 2008.^{[citation needed]}

On January 18, 2011, the University of Southern California announced the purchase of KUSF (90.3 MHz) from the University of San Francisco (USF) and KNDL (89.9 MHz) in Angwin, California. It also announced the purchase of the intellectual property and call letters of KDFC from Entercom, moving its programming to those two stations and making it a listener-supported non-commercial outlet with Lueth as its President. KUSF was renamed KOSC, and KNDL was renamed KDFC. In turn, Entercom flipped the 102.1 MHz frequency to a simulcast of San Jose station KUFX, which Entercom had acquired earlier in the month, on January 24.^[6][7] KUSF turned into an online-only radio station.^[3] The Federal Communications Commission officially transferred the 90.3 MHz license to the University of Southern California on June 7, 2012.^{[citation needed]}

On May 1, 2017, the KDFC call sign moved to 90.3 FM in San Francisco, swapping call signs with 89.9 FM in Angwin, which became KOSC.^[8][9]

KDFC broadcasts classical music 24 hours a day. Programming features include: Mozart In the Morning, the Island of Sanity, and San Francisco Symphony broadcasts. KDFC also airs recordings of San Francisco Opera productions. On-air personalities include Rik Malone, Dianne Nicolini, Robin Pressman, Hoyt Smith, Rich Capparela, Lara Downes and Jennifer Miller.

In addition to FM and SHOUTcast MP3 streaming, KDFC was the first radio station in the country to broadcast in digital HD Radio, offering a secondary HD Radio channel, KDFC-2, featuring longer classical pieces and vocal works, without commercials on their former 102.1 FM frequency.

A multiple winner of the award for public service, KDFC is an active partner to arts groups and an active advocate for music education. Proceeds from the station's annual CD sampler, and the annual 'Music Educator of the Year' support and celebrate public school music programs.

KDFC also extends its signal via full-power satellites KOSC/Angwin (89.9 FM), KDFG/Seaside (103.9 FM) and KXSC/Sunnyvale (104.9 FM), as well as a low-power translator K223AJ/Lakeport (92.5 FM). Another low-power translator, K212AA/Los Gatos (90.3 FM), is offline as of July 2024.^[10][11]

• Official website
• Facility details for Facility ID 69143 (KDFC) in the FCC Licensing and Management System
• KDFC in Nielsen Audio's FM station database
• FCC History Cards for KDFC

Translators

• Facility details for Facility ID 51716 (K212AA) in the FCC Licensing and Management System
• K212AA at FCCdata.org
• Facility details for Facility ID 27945 (K223AJ) in the FCC Licensing and Management System
• K223AJ at FCCdata.org

Repeaters

• Facility details for Facility ID 15936 (KDFG) in the FCC Licensing and Management System
• Facility details for Facility ID 27946 (KOSC) in the FCC Licensing and Management System
• Facility details for Facility ID 54478 (KXSC) in the FCC Licensing and Management System