The Sound of WWVB (60 kHz)

If our ears could hear the 60 kHz radio signal transmitted by radio station WWVB as a 1000 Hz tone, this is what it would sound like.

This is a one minute sample of WWVB's radio signal recorded on Februrary 1, 2009 beginning at 0246 UTC. Reception took place in New Jersey, over 1600 miles from WWVB's Fort Collins, Colorado transmitter using a specialized receiver of my own design.

WWVB's 50 kilowatt radio signal blankets the continental United States, and conveys the current time, year, day of the year, UT1 offset, leap second, and leap year information at a data rate of one bit per second. It is widely used in setting radio-controlled "atomic" clocks and watches, typically during nighttime hours when its signal is the strongest.

WWVB's carrier drops 17 dB in amplitude at the beginning of each second. It rises back to full power a fraction of a second later producing an amplitude shift keying signal. The number of milliseconds it takes to rise to full power after the start of each second conveys binary '0's (200 ms), '1's (500 ms), and frame 'M'arker pulses (800 ms) that receivers interpret to determine the current date and time.

Further information on WWVB is available at: http://tf.nist.gov/stations/wwvb.htm

Видео The Sound of WWVB (60 kHz) канала 5UP7