Time stations: WWV, WWVH and the end of CHU
A time station sounds like a clock ticking once a second, with a longer beep at the top of each minute and a voice announcing the time: a man's voice on WWV, a woman's on WWVH.
WWV2.5, 5, 10, 15, 20 MHz
WWVH2.5, 5, 10, 15 MHz
CHUClosed June 22, 2026
What does it sound like?
0 Hz1,0002,0003,000 Hz

0 Hz1,0002,0003,000 Hz

What are they?
Stations run by national standards laboratories that broadcast the exact time from atomic clocks. WWV, near Fort Collins, Colorado, and WWVH, on Kauai, Hawaii, are run by NIST and broadcast around the clock.
What am I hearing?
- A short tick every second (none at seconds 29 and 59).
- A longer beep at the top of each minute, higher-pitched on the hour.
- Steady tones of 500 or 600 Hz in alternate minutes, and 440 Hz (concert A) in some.
- The time spoken in English: WWV's man just before the minute, WWVH's woman a little earlier. Where both reach you, you hear them take turns.
The end of CHU
Canada's time station, CHU in Ottawa, went off the air permanently on June 22, 2026. It spoke the time in French and English, and a burst of modem-like data carried the time code. WWV and WWVH were proposed for closure in 2018 and kept by Congress.
Easily confused with
- Numbers stations: numbers too, but no ticking clock
- Unmodulated carrier: a steady tone with no one-second rhythm