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Operation Guide 3721
2
Positioning Your Arm Correctly
•
You should be wearing the watch on the outside of your wrist
when using the auto light switch.
•
Make sure that the left (9 o’clock) and
right (3 o’clock) sides of the watch are
within
±
15 degrees of being parallel
with the ground. The auto light switch
may not operate properly if the angle is
greater.
Important!
•
The light may be difficult to see if you turn it on under bright
sunlight.
•
If you press the
B
button or if an alarm operation starts while the
face is illuminated, illumination will turn off.
Auto Light Precautions
•
Frequent use of the auto light can run down the battery.
•
The auto light switch may cause the face to illuminate when your
sleeve covers the face of the watch.
•
The face may not illuminate immediately when you angle the
watch towards your face. This does not indicate malfunction.
•
The face remains illuminated for 1.5 seconds only, even if you
leave the watch angled towards your face.
•
The auto light switch is disabled automatically during 2-second
hand movement.
•
The face may illuminate unintentionally when you wear the watch
on the inside of your wrist, when you shake your arm, or when
you raise your arm. Be sure to turn off the auto light switch
whenever you do not need face illumination.
•
Keep the auto light switch turned off whenever you are wearing
the watch on the inside of your wrist.
•
Electro-static charge and magnetism can interfere with auto light
operation and even make operation impossible. If this happens
lower your arm to the starting position and then raise it again. If
you still have trouble with illumination, try lowering your arm down
to your side and then raise it to your face for reading.
Rotate your arm so the watch
is angled at about 40 degrees,
so you can read its face.
With the watch on
your wrist, position it
level with the ground.
1
1
1
1
1
2
2
2
2
2
At least
40
degrees
An LED light is used to illuminate the face of the watch for easy
reading in the dark. An auto light switch automatically illuminates
the face when you angle the watch towards your eyes for reading.
❚
To illuminate the face manually
In the Timekeeping Mode,
press the
A
A
A
A
A
button.
•
This illuminates the face for
about 1.5 seconds.
•
Pressing the
A
button illuminates the display regardless of
whether the auto light switch is on or off.
You may hear a faint rattling sound when you move the watch
around. This sound is caused by the movement of a metal
bulb that controls operation of the auto light switch, and does
not indicate malfunction.
❚
To illuminate the face with the auto light
switch
The auto light switch automatically illuminates the face
whenever you angle the watch towards your eyes for reading,
but only when it is dark.
•
The auto light switch does not illuminate the face when
surrounding light is bright.
The auto light switch will illuminate the face for about 1.5
seconds in any mode.
❚
To turn the auto light switch on and off
In the Receive Result Mode, hold down the
A
button for about
three seconds to toggle the auto light switch on and off.
Face Illumination
Location
Reception is difficult and may even be impossible in the locations
described below. Avoid such locations when performing signal
reception.
•
You should think of your watch operating like a radio or TV when it
is receiving the calibration signal.
If you are experiencing problems with reception, move away
from the types of locations described above to a location with
better reception, and try again.
Reception Range
This watch is designed to receive either the Mt. Otakadoya signal
(40kHz) or the Mt. Hagane signal (60kHz), whichever is strongest.
1000km
Mt. Hagane
(60kHz)
Mt. Otakadoya
(40kHz)
500km
1000km
500km
Transmitter Locations
•
Under optimum conditions, the calibration signal should be
receivable up to 1,000 kilometers from the transmitter. Note
that the wave is relatively weak at distances greater than
500km, so reception may be poor at long distances.
•
Geographic contours, nearby buildings, seasonal conditions, the
time of day, can even make reception impossible even when you
are within the range of the transmitter.
•
Reception is best at night.
What is a radio-controlled watch?
Your radio-controlled watch is designed to receive a time
calibration signal that contains standard time data, and adjust its
current time setting accordingly.
Signal data
Transmitter
Internally
Decode
Watch
Time data
Long-wave
time
calibration
signal
Cesium
atomic clock
Signal is received using
built-in antenna.
Watch decodes
received data
and converts it
to time data.
Time is adjusted
according to
time data.
After the watch receives the Standard Time signal, it performs
internal calculations to determine the current time. Because of
this, there may be an error of up to one second in the
displayed time.
Calibration Signal
•
The Japanese calibration signal (Call Sign: JJY) is maintained by
the National Institute of Information and Communications
Technology (NICT). It is a long wave signal transmitted 24 hours a
day from the Mt. Otakadoya transmitter (40kHz) located in
Tamura-gun, Fukushima Prefecture, and from the Mt. Hagane
transmitter (60kHz) located on the border between Saga
Prefecture and Fukuoka Prefecture.
Note that transmission of the time calibration signal may be
interrupted occasionally due to maintenance, lightning, etc.
How a Radio-controlled Watch Works
Near high-voltage lines
Among or near buildings
Inside a vehicle
(automobile, train, plane, etc.)
In a location where there is
radio interference (construction
site, airport, etc.)
Next to a household
appliance or office equipment
(TV, speaker, fax, computer,
cell phone, etc.)
Near mountains