From 1939 to 1950, Mutual Broadcasting System covered the Indianapolis 500 nationwide with live segments at the start, the finish, and live periodic updates throughout the race. Bill Slater was brought in as the anchor. In the years prior to World War II, Mutual used the production services of WLW, and provided the signal to other Mutual stations across the country. In the years after World War II, Mutual utilized the services of WIBC to produce the broadcast and provide additional talent.