1939 the FCC began encouraging Apex stations to consider changing to the technically superior FM transmissions. In May 1940, the FCC decided to authorize a commercial FM band effective January 1, 1941, operating on 40 channels spanning 42–50 MHz. (This was later changed to 88–106 MHz, and still later to 88–108 MHz, which increased the number of channels to 100.) This new assignment also resulted in the elimination of the Apex band, and the Apex stations were informed that they needed to either go silent or convert to FM. With this change, a few of the original Apex stations were converted into some of the earliest FM stations. The three educational stations were allowed some leeway in making the conversion to FM, with WBOE switching over in February 1941, WNYE receiving permission to continue as an Apex station until June 29, 1941, and WBKY receiving a series of authorizations to continue using its AM transmitter until May 1, 1944. Currently, the frequencies that had been used by the Apex band are allocated for land mobile communication. There would be at least one attempt to revive the Apex band concept. Beginning in May 1946, consulting radio engineer Sarkes Tarzian operated a 200-watt experimental AM station, W9XHZ, on 87.75 MHz in Bloomington, Indiana. After two years of successful operation of what he referred to as his "HIFAM" station, in 1948 he proposed that the FCC allocate a small high-frequency broadcast band, 400 kHz wide with 10 kHz spacing between frequency assignments. Tarzian promoted this as a low-cost alternative to expensive FM transmitters and receivers, saying that a $5.95 converter could be added to existing AM radios that would allow them to pick up the HIFAM stations. He continued to operate his experimental station, which eventually became KS2XAP, until 1950, although by then its transmitting hours were greatly restricted, as the FCC required the station to remain off the air whenever nearby WFBM-TV in Indianapolis was broadcasting. This was due to the fact that the TV station's audio transmitter used the same frequency as Tarzian's station. Moreover, after his station's final license expired on June 1, 1950, the FCC denied Tarzian any further renewals, concluding it would not reverse its earlier determination that there was no need for a second AM broadcast band. Notes References External links America's Apex Broadcasting Stations of the 1930s by John Schneider, Monitoring Times Magazine, December 2010. (theradiohistorian.org)