KKSF (910 AM) is a licensed broadcasting commercial radio station coming out of Oakland, California. The station is owned by iHeartMedia and serves the San Francisco-Oakland-San Jose media market. It operates as the Bay Area affiliate for the Black Information Network. The transmitter and twin tower array are located on Point Isabel in Richmond, on the San Francisco Bay. KDIA utilizes one of KKSF's two towers during the day. KKSF operates at 20,000 watts during the day and 5,000 watts at night, using a directional antenna at all times. Because radio waves travel farther at night, KKSF must reduce its power after sunset to protect other stations on AM 910. KKSF's studios are located in San Francisco's SoMa district. History KLX KKSF was started by the Oakland Tribune newspaper. Beginning in early 1922, the Tribune had supplied content for Preston D. Allen's station, KZM, located atop the Oakland Hotel. Following a suggestion by Allen, the newspaper decided to establish its own broadcasting station, and on May 3, 1922 was issued a license with the randomly assigned call letters of KLX. This designated operation on the standard "entertainment" wavelength of 360 meters (833 kilohertz). KLX's debut sign-on occurred at 7:30 p.m. on July 25, 1922. For the first year and a half, KLX shared the studios and transmitter at the Oakland Hotel with KZM. Engineer Roswell Smith remembered that "they used to shut down the transmitter as KZM, and take to the air a half hour later as KLX". As part of the cooperative effort, the Herald arranged to upgrade the KLX's 5-watt transmitter by installing two more powerful transmitters, which were named for characters in the Toonerville Folks comic strip: 50-watt "Little Jimmie", and 250-watt "Powerful Katrinka." Initially the 360-meter wavelength was the only "entertainment" frequency available, so stations within various regions had to develop timesharing agreements providing for each station to broadcast for a few hours each week. By November 1, 1922, there were twelve "San Francisco Bay District" stations sharing time on 360 meters, and, after KZM ceded its original hours, KLX was assigned 7:00-7:30 p.m. daily except Sunday, plus 10:00-11:00 a.m. Sunday and 8:00-9:00 p.m. Tuesday. In the fall of 1923, KLX moved to its own studio on the 20th floor of the recently completed Tribune Tower at Thirteenth and Franklin, where it would be for the next thirty years. An antenna was strung between the tops