Radio Controlled Atomic Timekeeping
This watch receives a time calibration signal and updates its time setting accordingly. However, when
using the watch outside of areas covered by time calibration signals, you will have to adjust the settings
manually as required. See "Conﬁ guring Current Time and Date Settings Manually" for more information.
This section explains how the watch updates its time settings when the city code selected as the Home
City is in Japan, North America, Europe, or China, and is one that supports time calibration signal
If your Home City Code setting is this:
LIS, LON, MAD, PAR, ROM, BER, STO, ATH, MOW
TPE, SEL, TYO
HNL, ANC, YVR, LAX, YEA, DEN, MEX, CHI, NYC, YHZ,
The areas covered by MOW, HNL and ANC are quite far from the calibration signal transmitters, so
certain conditions may cause reception problems.
When HKG or BJS is selected as the Home City, only the time and date are adjusted according to the
time calibration signal. You need to switch manually between standard time and daylight saving time
(DST) if required. See "To conﬁ gure Home City settings" for information about how to do this.
Approximate Reception Ranges
UK and German Signals
The Anthorn signal is
receivable within this area
Signals are receivable in the Taiwan area
when reception conditions are good.
Even when the watch is within range of a transmitter, signal reception may be impossible due to the
effects of geographic contours, structures, weather, the time of year, the time of day, radio interference,
etc. The signal becomes weaker at distances of approximately 500 kilometers, which means that the
inﬂ uence of the conditions listed above becomes even greater.
Signal reception may not be possible at the distances noted below during certain times of the year or
day. Radio interference may also cause problems with reception.
Mainﬂ ingen (Germany) or Anthorn (England) transmitters: 500 kilometers (310 miles)
Fort Collins (United States) transmitter: 600 miles (1,000 kilometers)
Fukushima or Fukuoka/Saga (Japan) transmitters: 500 kilometers (310 miles)
Shangqiu (China) transmitter: 500 kilometers (310 miles)
As of January 2009, China does not use Daylight Saving Time (DST). If China does go to the Daylight
Saving Time system in the future, some functions of this watch may no longer operate correctly.
To get ready for a receive operation
1. Conﬁ rm that the watch is in the Timekeeping Mode. If it isn't, use D to enter the Timekeeping Mode.
2. The antenna of this watch is located on its 12 o'clock side. Position the watch with 12 o'clock facing
towards a window as shown in the nearby illustration. Make sure there are no metal objects nearby.
Signal reception may be difﬁ cult or even impossible under the conditions described below.
or a mobile
3. What you should do next depends on whether you are using Auto Receive or Manual Receive.
Auto Receive: Leave the watch over night in the location you selected in step 2. See "Auto
Receive" below for details.
Manual Receive: Perform the operation under "To perform manual receive".
Operation Guide 3172
The watch can receive the signal from the transmitter
Anthorn (England), Mainﬂ ingen (Germany)
Shangqiu City (China)
Fukushima (Japan), Fukuoka/Saga (Japan)
Fort Collins, Colorado (United States)
North American Signal
Signal reception normally is better at night.
The receive operation takes from two to seven minutes,
but in some cases it can take as long as 14 minutes. Take
care that you do not perform any button operation or
move the watch during this time.
With Auto Receive, the watch performs the receive operation each day automatically up to six times (up
to ﬁ ve times for the Chinese calibration signal) between the hours of midnight and 5 a.m. (according to
the Timekeeping Mode time). When any receive operation is successful, none of the other receive
operations for that day are performed.
When a calibration time is reached, the watch will perform the receive operation only if it is in the
Timekeeping Mode or World Time Mode. The receive operation is not performed if a calibration time is
reached while you are conﬁ guring settings.
You can use the procedure under "To turn auto receive on and off" to enable or disable auto receive.
To perform manual receive
If there was a previously
If there was a previously
If no reception was
If no reception was
Signal Level Indicator
Signal level indicator
Signal level indicator
To check the latest signal reception results
To turn auto receive on and off
1. Use D to select the Receive Mode (R/C) as shown in "Selecting a
2. Hold down A.
Keep A depressed until RC Hold appears on the display and the
receiving indicator starts ﬂ ashing.
A signal level indicator (L1, L2, or L3, see "Signal Level Indicator")
appears on the display after reception starts. Do not move the
watch or perform any button operation until GET or ERR appears
in the upper left corner of the screen.
If the receive operation is successful, the reception date and time
appear on the display, along with the GET indicator.
The watch will return to the Timekeeping Mode if you press D or
if you do not perform any button operation for about two or three
If the current reception fails but a previous reception (within the
last 24 hours) was successful, the display shows the receiving
indicator and the ERR indicator. If the ERR indicator only is
displayed (without the receiving indicator), it means that all of the
receive operations over the past 24 hours have failed.
The watch will return to the Timekeeping Mode without changing
the time setting if you press D or if you do not perform any button
operation for about two or three minutes.
To interrupt a receive operation and return to the Receive Mode, press
During manual receive, the signal level indicator displays the signal level
as shown below.
As you watch the indicator, keep the watch in a location that best
maintains stable reception.
Even under optimum reception conditions, it can take about 10
seconds for reception to stabilize.
Note that weather, the time of day, surroundings, and other factors all
can affect reception.
Enter the Receive Mode.
When receive is successful, the display shows the time and date that
receive was successful. - : - - indicates that none of the reception
operations were successful.
To return to the Timekeeping Mode, press D.
The receiving indicator will not be displayed if you have adjusted the
time or date setting manually since the last receive operation.
1. Enter the Receive Mode.
2. In the Receive Mode, hold down E until the current auto receive
setting (On or OFF) and receiving indicator start to ﬂ ash. This is the
Note that the setting screen will not appear if the currently selected
Home City is one that does not support time calibration reception.
3. Press A to toggle auto receive on (On) and off (OFF).
4. Press E to exit the setting screen.