KTSL is one of the youngest radio stations in Spokane, having begun transmissions in 1991, initially calling itself "The Word In Music" and later "Power 101.9", to reflect a Christian rock style. In July 2001, Power 101.9 changed its name to "Spirit 101.9", also changing its format to a more worship-styled music. On July 4, 2005, amid a loss of ratings due to its recent format change, Spirit 101.9 changed its format back to a Christian rock style, calling itself "101.9 Spirit FM". As of May 2008, KTSL is broadcasting the Air 1 Radio Network, an adult contemporary format relying heavily on well established songs combined with a heavy dose of worship music. The KTSL call letters were previously used on channel 2 in Los Angeles, now KCBS-TV.