Operation Guide 3719
4
• The watch is designed to update the date and day of the week automatically for the
period January 1, 2000 to December 31, 2099. Setting of the date by the time
calibration signal cannot be performed starting from January 1, 2100.
• This watch can receive signals that differentiate between leap years and non-leap
years.
• Though this watch is designed to receive both time data (hour, minutes, seconds)
and date data (year, month, day), certain signal conditions can limit reception to time
data only.
• If you are in an area where proper time calibration signal reception is impossible, the
watch keeps time within ±20 seconds a month at normal temperature.
In this case:
The first signal search operation after
factory default settings are in effect.
The first signal search operation after
the Home Time Zone has been
changed.
The watch does this:
1. Checks the Mainflingen signal first.
2. If the Mainflingen signal cannot be
received, checks the Rugby signal.
1. Checks the Rugby signal first.
2. If the Rugby signal cannot be received,
checks the Mainflingen signal.
• If you have problems with proper time calibration signal reception or if the time
setting is wrong after signal reception, check your Home Time Zone (GMT
differential) setting.
Transmitters
This watch is able to receive time calibration signals transmitted in Germany
(Mainflingen) and England (Rugby). The following explains how the watch determines
which transmitter it should check first.
Timekeeping
• The year can be set in the range of 2000 to 2099.
• The watch’s built-in full automatic calendar makes allowances for different month
lengths and leap years. Once you set the date, there should be no reason to change
it except after you have the watch’s battery replaced or when battery power drops to
Level 3.
• The date will change automatically when the current time reaches midnight. The
date change at the end of the month may take more time than normal.
• The times for the Timekeeping Mode are calculated in accordance with each city’s
UTC differential.
• The UTC differential is a value that indicates the time difference between a
reference point in Greenwich, England and the time zone where a city is located.
• The letters “UTC” is the abbreviation for “Universal Time Coordinated”, which is the
world-wide scientific standard of timekeeping. It is based upon carefully maintained
atomic (cesium) clocks that keep time accurately to within microseconds. Leap
seconds are added or subtracted as necessary to keep UTC in sync with the Earth’s
rotation.
Power Saving
Power Saving enters a sleep state automatically whenever the watch is left for a
certain period in an area where it is dark. The table below shows how watch functions
are affected by Power Saving.
• There are actually two sleep state levels: “second hand sleep” and “function sleep”.
Operation
Second hand only is stopped, all other functions are
enabled.
• All functions, including analog timekeeping, disabled
• Internal timekeeping maintained
Elapsed Time in Dark
60 to 70 minutes
(second hand sleep)
6 or 7 days
(function sleep)
• Wearing the watch inside the sleeve of clothing can cause it to enter the sleep state.
• The watch will not enter the sleep state between 6:00 AM and 10:59 PM. If the
watch is already in the sleep state when 6:00 AM arrives, however, it will remain in
the sleep state.
To recover from the sleep state
Perform any one of the following operations.
• Move the watch to a well-lit area.
• Press any button.
• Angle the watch towards your face for reading.
• Even if the time calibration signal is received properly, certain conditions can cause
the time setting to be off by up to one second.
• The current time setting in accordance with the time calibration signal takes priority
over any time settings you make manually.
