9XM - WHA

On this campus, pioneer research and experimentation in wireless led to successful transmissions of voice and music in 1917 and the beginning of broadcasting on a scheduled basis in 1919. Experimental station 9XM transmitted telegraphic signals from Science Hall until 1917, when it was moved to Sterling Hall. In that year, professor Earle M. Terry and students built and operated a wireless telephone transmitter. In 1918, during World War I, when other stations were ordered silenced, 9XM operated under special authorization to continue its telephonic exchange with U.S. Navy stations on the Great Lakes. After the war, programs were directed to the general public. The WHA letters replaced the 9XM call on January 13, 1922. Thus, the University of Wisconsin station, under the calls 9XM and WHA, has been in existence longer than any other.

Madison, Wisconsin · United States