[8] As of 1916, university electrical engineering students were operating a 2,000 watt spark gap transmitter at a 750-meter wavelength that could be heard 1000 miles away, with two-way communications taking place within a 500-mile radius.
[10] Carl Menzer, whose interest in wireless began at his high school in Lone Tree, entered the State University of Iowa as a freshman in 1917, and later became station director for WHAA/WSUI, a position he held until his retirement in 1968.
After the World War I moratorium on radio transmission was lifted in 1919, Menzer brought vacuum tube technology to 9YA, signaling the start of regularly scheduled voice and music broadcasts.
[11] The first "radio telephone" station, built using two donated experimental vacuum tubes, required use of two microphones for voice and for pickup of a windup phonograph.
In spite of audio quality and technical issues, the station gained a following among a collection of crystal radio enthusiasts.
[12] Within two years, it had inspired sufficient interest to cause State University of Iowa President Walter A. Jessup and other educators to envision the feasibility of advanced study in broadcasting.
Despite this change, stations in Iowa that already had W call signs were apparently allowed to request new ones: besides WSUI, WJAM became WMT in 1928, and WKBB became WDBQ in 1952.
It also served as a source of NPR programming for the Quad Cities until that area got its own public radio station, WVIK, in 1980.
They were relocated to a former supermarket building, just south of the campus, in the late 1990s, when expansion of the College of Engineering required WSUI and KSUI to vacate their space.
Power is fed to all three towers in a directional array at night to protect WLS in Chicago at nearby 890 AM, concentrating WSUI's signal northward toward the Cedar Rapids and Iowa City areas.
[18] In 1951, the university supported the reallocation of channel 11 to Des Moines for an educational television station there, and its own permit does not appear in any further records.