KIRO (710 kHz "Seattle Sports") is a commercial AM radio station in Seattle, Washington, owned by Salt Lake City–based Bonneville International. The station airs a sports radio format and is an ESPN Radio Network affiliate. The station's studios and offices are located on Eastlake Avenue in Seattle's Eastlake district. KIRO is a Class A clear channel station. It broadcasts at the maximum power for commercial AM radio stations, 50,000 watts. By day, it uses a non-directional antenna. But to protect the other Class A station on AM 710, WOR New York City, and the previously allocated Class B station on 710, KSPN in Los Angeles, KIRO must use a directional antenna at night, thereby protecting those two older stations. The transmitter is off Dockton Road SW on Vashon Island. KIRO is Washington State's primary entry point station in the Emergency Alert System. History 650 KPCB (1927 to 1937) The station began broadcasting on April 27, 1927, as KPCB on 650 kilocycles. Its founder was Moritz Thomsen of the Pacific Coast Biscuit Company (hence the call sign KPCB) and it was powered at 100 watts. Among its announcers was Chet Huntley, later of television's Huntley-Brinkley Report. In 1935, Saul Haas's Queen City Broadcasting Company took over the station. Queen City increased the power to 500 watts. Haas, who was well connected in liberal politics and the business community, wanted a simple, pronounceable, and recognizable call sign for his new station. He chose KIRO, which is usually pronounced like the capital of Egypt, "Cairo", not like the Illinois city. The call sign "KING," representing King County, Washington, the county in which Seattle is found, was not available at that time. The KING call letters were later used by a station on AM 1090 (now KPTR), and continue on both FM classical music station KING-FM (98.1) and KING-TV (channel 5). 710 KIRO (1937 to 1960) In 1937, KIRO was assigned the AM 710 frequency and was granted an increase in power to 1,000 watts. Soon after, KIRO acquired the Seattle CBS Radio Network affiliation rights from KOL. Known as "The Friendly Station," KIRO personalities broke from the formal announcing style that was commonplace during the early days of radio. KIRO carried CBS's dramas, comedies, news, sports, soap operas, game shows and big band broadcasts during the "Golden Age of Radio." On June 29, 1941, a new, 50,000-watt transmitter on Maury Island became operational.