WCAL first experimented with FM broadcasts in 1948. Broadcasts on 89.3 FM were officially launched on October 1, 1967 as a sister to the established AM, which was one of the first radio stations in the state. A few years later in 1971, WCAL became one of 90 founding members of National Public Radio organized by the Corporation for Public Broadcasting. WCAL-FM was operated by St. Olaf for over 37 years and was known as "Classical 89.3" later in its history, playing what many considered to be "alternative" classical music along with a variety of sacred music and religious programming.