Radio-controlled timepiece and control method for the same

Abstract

A watch has a crown for manual time adjustment, a receiver for receiving current time update signals by radio transmission, an internal counter for counting the passage of time according to an internal oscillator, and time display hands. The watch preferably does not have a means for determining the position of its time display hands and therefore relies on user intervention for roughly correlating its time display hands to its internal counter. Preferably, the user begins a manual time correction operation when the second hand is at a predetermined position between 0-60 seconds. When the crown is pushed in, the seconds count value of the internal counter is reset to the predetermined position, and the watch waits for reception of a current time radio signal. When a radio signal is successfully received, the received seconds value is compared to the seconds count in the internal counter. If the time difference is within +30 seconds, the internal time is deemed to be advanced by the difference, and if the time difference is within −30 seconds, the internal time is deemed to be delayed by the difference. The received time data is written into the internal counter, and the time display hands are moved according to the deemed time difference.