Casio Wave Ceptor

Casio Wave Ceptor is a line of radio watches by Casio. Wave Ceptor watches set themselves to the correct time by receiving time signals from various government time services around the world. These signals transmit the time measured by atomic clocks accurate to one second in millions of years; by synchronizing daily with the signals, the Wave Ceptor watches achieve high accuracy, running with quartz timekeeping accuracy between synchronizations.

Radio-controlled watches require no setting of time, date, or daylight saving time; and like most other watches of this kind, they attempt automatic synchronization at least once every 24 hours, usually in the middle of the night. Free-running Wave Ceptors, like other commercial quartz timepieces, are typically accurate to better than 15 seconds per month; daily synchronization ensures 500 ms per day accuracy.

As with all radio-controlled watches they revert to free-running quartz watch operation in areas out of range or shielded from time signals, which gives them the accuracy of a standard quartz watch.

The receivers to which the watches can tune vary by watch submodel. Casio says that in Europe the watches tune to the 77.5kHz low frequency time signal radio station DCF77 at Mainflingen in Germany, or 60kHz MSF at Anthorn (formerly transmitting from Rugby, Warwickshire) in the United Kingdom. In Europe the reception range is approximately 1,500 kilometres. In the United States they tune to the 60kHz signal from WWVB at Fort Collins. In Japan they tune to the 40kHz signal from JJY at Mount Otakadoya, near Fukushima (Ohtakadoyayama) and the 60kHz signal from the Haganeyama Transmitter at Mount Hagane (Haganeyama). In China they tune to the 68kHz signal from BPC at Shangqiu. Some watches can tune to several signals; if not able to receive any, for example when travelling in a different region, they function as quartz watches.

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