Radio station WRR, the United States' first fire and police dispatch network, originated in 1920 thanks to the innovative thinking of Dallas police and fire signal superintendent Henry Garrett, who realized the potential of communicating via the then brand-new medium of wireless radio transmission. When dispatchers began broadcasting music between fire alarms, citizens listened on their homemade sets, and the Dallas, Texas, radio station was born. In August 1921, operating with 50 watts, WRR became the first federally licensed radio station west of the Mississippi River and the second in the United States. During the last 103 years, the WRR call letters have been at the heart of both an AM and an FM station, and North Texas listeners eagerly tuned in to both frequencies.