The station's growth has covered one of the most interesting and turbulent periods in American history. The era has witnessed the "Roaring Twenties," prohibition, gangland wars, the Great Depression, FDR, the Spanish Civil War, World War II, the formation of the United Nations, the nuclear age, the Korean War, the space age and American Astronauts making the world's first-ever landing on the moon. Then came the Vietnam War, the assassinations of a President, Senator and civil rights leader; Watergate and the subsequent resignation of President Nixon, actor Ronald Reagan becoming the country's 40th President, the Persian Gulf War, the disintegration of the USSR, and other events shaping our time. Most recently, KNX provided exclusive live coverage fo the O.J. Simpson murder trial, what many are calling the "Trial of the Century."

Fred Christian, an ex-Marconi shipboard wireless operator on the "Middlesex" in 1919, put together a five-watt transmitter, the forerunner of KNX, in his Hollywood home. He was first granted the call letters 6 ADZ, later changed to KGC, and finally to KNX. Christian began broadcasting on September 10, 1920 by playing recorded music borrowed from music stores in return for plugs on the air.
He was the city's first disc jockey and his "studio" was a back bedroom in his home on Harold Way, located between Normandie Avenue and Mariposa Street.

Operating an amateur radio "station" was not Christian's vocation. He was manager of the Electrical Lighting Power Company, which sold radio parts to people trying to build their own sets, because according to Christian, there were no commercial radio sets for sale prior to 1923. "People were buying parts to build radio sets. They had to have something to listen to, so I put the transmitter together," Christian explained.

News was given first priority every night, Christian remembers, "At a time when I had KNX (1920-1924), the general trend of thought was that news was just a novelty that would run its course and fade away. However, I felt differently about it. I believed in the future of radio as a prime news source, as well as an entertainment medium."

By the Summer of 1922, some 22 other stations in and about the Los Angeles area had been licensed to broadcast. These all shared the single wave length of 360 meters. The rivalry between these operations was intense, and it "took some doing" to determine the hours each station would operate. Christian, with his large orchestra and beautiful theater organ, usually was able to function during the "choice hours" of 7 to 10 PM three times a week.

Out of this chaos of early day broadcasting in the Los Angeles area, KNX was one of the only three stations to emerge with a long history of continuous operation.

IN 1929, KNX became a 5,000-watt station. In 1932 it won another power boost to 10,000 watts, and was under the ownership of the Western Broadcasting Company, which broadcast from the old Paramount lot on Marathon Street in Hollywood. Another power jump to 25,000 watts came in 1933 when KNX moved its studios to the Otto K. Oleson Building at Vine Street and Selma Avenue. The following year (1934) was a memorable one for KNX when it was granted 50,000 watts of power, which it still utilizes. A year later, KNX moved its operations to a new building at 5939 Sunset Boulevard. Finally in 1936, 16 years after its birth, KNX found a permanent home with the Columbia Broadcasting System, Inc. Within a short time, eight network programs were originating from the KNX Hollywood studios.

This rapid increase in broadcast operations resulted in the need for more space. Thus, ground was broken in 1937 for the new KNX/CBS Studios on Sunset Boulevard, between Gower and El Centro Streets. This had been the site of the Al Christie Studios where the Hollywood motion picture industry was born.

From this broadcast center the nation's most memorable and foremost radio programs were beamed. Long lines of fans extended around the forecourt of Columbia Square before and during World War II to attend their favorite radio shows. Among the CBS Radio stars were Eddie Cantor, Al Jolson, Jack Benny, Gene Autry, Steve Allen, Stu Erwin, Jack Oakie, Jeanette MacDonald, Edgar Bergen, Bing Crosby, Orson Welles, Red Skelton, Jackie Gleason, Burns and Allen, Rosemary Clooney, Ed Wynn and others.

After 67 years at Columbia Square in Hollywood, KNX 1070 moved to new facilities on Wilshire Boulevard's 'Miracle Mile' in August 2005.