CHU shortwave time signal to go dark June 22, 2026

The Government of Canada’s CHU shortwave station—long used to synchronize clocks—will stop transmitting on June 22, 2026, ending decades of Morse code, bilingual speaking clock broadcasts, and pulse/DUT1 plus modern digital FSK timing.

For years, CHU has been quietly keeping the world in sync—first with Morse code, later with a speaking clock, and eventually with time codes designed for everything from older radio clocks to modern digital gear. But the steady rhythm won’t last forever.

The National Research Council of Canada’s CHU station, broadcast on 3330, 7850, and 14 670 kHz, is scheduled to go dark on June 22nd, 2026. After that date, listeners who still tune in for those time signals will no longer find the station on the dial.

Depending on where you live, CHU’s frequencies could be easier or harder than alternatives. In the United States, WWVB has played a similar role. Europe has its own set of options, including DF44, while the UK uses MSF. Whether you’re listening through a shortwave receiver or building equipment around radio timing. they all share the same basic job: tell the time.

CHU has done that in more than one way since its establishment in 1923. The early era relied on Morse code, sending time the way radio operators have always done. Later, the station added a speaking clock so people could listen directly—available in both Canadian French and English.

For synchronizing radio clocks, CHU uses multiple timing formats across generations of equipment. Older clocks listen for a series of pulses in DUT1 format, using 0.3s pulses. More modern equipment, meanwhile, can use a digital FSK time code. Those choices reflect the same practical goal, adapted over time as radios and clock hardware evolved.

There’s a human side to the end of a signal like this. The piece of practical infrastructure isn’t just technical—it’s familiar. The beeps and tones have a kind of staying power, and it’s hard not to feel the loss when a long-running station is told to shut down.

The Government of Canada’s decision is framed as an effort to save money where it can. The article points to a similar situation with WWVB, which was also once in danger of shutting down for the same kinds of reasons. Even with that context, the change still lands as something to miss.

If you want to catch CHU while it’s still on, the station is expected to continue issuing QSL cards—QSLs are typically used as confirmations for radio contacts or reception—for as long as it’s broadcasting. Get them before it’s gone forever.

And for anyone depending on this timing signal, there’s no need to panic. The guidance is simple: don’t rely on CHU indefinitely. You can shift to another method, such as using a GPS time source, and even make your own clock setup around that timing input.

The end date is fixed. The frequencies—3330, 7850, and 14 670 kHz—have stayed readable for a long time. After June 22nd, 2026, CHU’s time signals will stop arriving at the exact moment the world has been trained to listen for them.

CHU time signal shortwave radio time synchronization DUT1 FSK time code GPS time source QSL cards WWVB MSF DF44 National Research Council of Canada