An analog clock automatically performs daily checks to ensure it's operating as expected.
At six pre-scheduled times a day, at 2:01 AM/PM, 6:01 AM/PM, and 10:01 AM/PM clock time (not the actual time of the day), a clock's receiver turns on to search for a Transmitter signal to receive a time update, starting with the previously stored channel number. If a signal is not received from the first channel, the clock scans all channels to search for a signal.
When a clock has not received a signal from the Transmitter for three consecutive days, its second hand begins to step twice at two second intervals to call attention to a problem with the clock. This pattern is repeated and the clock may display the correct time, but it's not synchronized and its time may drift.
The stepping pattern continues until the clock receives a valid time signal from the Transmitter. Once a valid time is received, the clock hands are set to the correct time and resume moving normally.