WWV (radio station)
WWV is the call sign of the United States National Institute of Standards and Technology's (NIST) HF ("shortwave") radio station located near Fort Collins, Colorado. WWV continuously transmits official U.S. Government frequency and time signals on 2.5, 5, 10, 15 and 20 MHz. These carrier frequencies and time signals are controlled by local atomic clocks traceable to NIST's primary standard in Boulder, Colorado by GPS common view observations and other time transfer methods. NIST also operates the very similar radio station WWVH in Kauai, Hawaii. WWV shares its site near Fort Collins with radio station WWVB which transmits carrier and time code (no voice) on 60 kHz in the LF ("longwave") band.
Both WWV and WWVH announce the Coordinated Universal Time each minute, and make other recorded announcements of general interest on an hourly schedule, including the GPS satellite constellation status and severe oceanic weather warnings. Since they share frequencies, WWV uses a male voice to distinguish itself from WWVH, which uses a female voice. WWV time signals can also be accessed by telephone.
WWV is the oldest continuously-operating radio station in the United States, first going on the air from Washington, D.C. in May 1920, approximately six months before the launch of KDKA. The station first broadcast Friday evening concerts on 600 kHz, and its signal could be heard 40 kilometers (25 mi) from Washington. On December 15, 1920, WWV began broadcasting on 750 kHz, distributing Morse code news reports from the Department of Agriculture. This signal could be heard up to 300 kilometers (190 mi) from Washington. These news broadcasts ended on April 15, 1921.
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