The Bramwell Brown Blog

What is a Radio-Controlled Wall Clock?

Radio Controlled Clock Masts

Not to be confused with a clock radio, which might be your alarm clock, the radio clock is controlled by a radio transmitter that synchronizes the time with a highly accurate time keeper like an atomic clock. For those wanting the most precise timepiece, a radio-controlled clock is your best bet.

Atomic clocks around the world keep time by using the vibrations of a Cesium 133 atom. The amount of vibrations is a constant that we use to measure the passing of one second, and it’s kept in check by a feedback detector that will help correct any frequencies that are off. It’s very similar to quartz clocks, which most of us have, but more accurate because it’s not affected by outside factors like temperature. The accuracy of an atomic clock is astounding because it won’t be off by more than two nanoseconds, if even that.

A picture of an atomic Clock

The time from the atomic clock is then broadcast by low-frequency radio waves that are stable enough to travel 1000 miles from its origin and follow the curvature of the Earth. The radio-controlled clock picks up these signals with its antennae and can keep precision time with the world’s most accurate clocks.

Though you can manually set a radio-controlled clock, the adjustments from its incoming radio messages keep it running smoothly and in sync with a more accurate atomic clock. A radio clock is more than just a time counter, adding seconds and minutes to the time you set it—it’s a time keeper that you can rely on.

For the best performance of a radio-controlled clock, the ideal spot for it is away from devices that may interfere with the radio waves, like the television or computer. Strong electrical activity like a wild storm can make the clock less accurate until it passes and you’ll always want to ensure that you’ve got new batteries installed. Since most atomic clocks will account for Daylight Savings, you may want to deactivate that function by pushing the DST button so your time is still accurate if you’re living not in a DST region.

Radio-controlled clocks come in all forms, so wherever you need an accurate timepiece, you’re not limited to your particular style. Wall clocks are a classic choice, especially for an office space where time is an important part of planning your day, but there are also desk clocks and watches that are atomically-coordinated. Whatever your need, you can stay on time with a radio-controlled clock.