How A Radio-Controlled Watch Works - Casio QW-3329 Operation Manual

Specifying the Illumination Duration
1.
In the Timekeeping Mode,
hold down A A A A A for about
two seconds.
• This will cause your city code
to flash in digital display.
City Code
2.
Press the C C C C button three C
times to display the
flashing seconds count.
(3 times) Seconds
Reception Range
This watch is designed to receive the standard time calibration signal of Japan (JJY) or of the United States (WWVB). The signal that is
received depends on the current Home City setting.
• For information about selecting a Home City, see "Configuring Home TIme Settings". For information about city codes, see the "World Time
City Code List".
Home City
TYO Either the Mt. Otakadoya signal (40kHz) or the Mt. Hagane signal (60kHz)
LAX, DEN, CHI, NYC Fort Collins, Colorado signal
Japan Transmitter
1000km
Locations
Mt. Otakadoya
500km (40kHz)
500km
Mt. Hagane
(60kHz)
1000km
• 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
range of the transmitter.
• Best reception is possible late at night.
Operation Guide 3329
3.
B B B button to
Press the B B
toggle the illumination
duration between about
1.5 seconds ( indicator)
and 3 seconds
( indicator).
4.
After the setting is the way you want, press the A A A A A
button to exit the setting screen.
• The watch will also exit the setting screen automatically if you
do not perform any operation for about two or three minutes.
Transmitter
U.S. Transmitter
Location
3000km
1000km
Fort Collins
• Under optimum conditions, the calibration signal should be
receivable up to 3,000 kilometers from the transmitter. Note
that the wave is relatively weak at distances greater than
1,000km, so reception may be poor at long distances.

How a Radio-controlled Watch Works

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 is received
Long-
wave time using built-in antenna.
Transmitter
calibration
signal
Watch decodes
received data and
converts it to time
Signal data
data.
Decode
Time data
Time is adjusted
Cesium
according to time
atomic clock
Watch Internally
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.
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.
Among or near buildings Near high-voltage lines
Inside a vehicle (automobile, Next to a household appliance or
office equipment (TV, speaker,
train, plane, etc.)
fax, computer, cell phone, etc.)
In a location where there is
Near mountains
radio interference
(construction site, airport, etc.)
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.
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.
• The U.S. calibration signal (Call Sign: WWVB) is transmitted by
the National Institute of Standards and technology from Fort
Collins, Colorado.
Note that transmission of the standard wave may be
interrupted occasionally due to maintenance, lightening, etc.
Receiving the Calibration Signal
There are two methods you can use to receive the time calibration signal.
• Auto receive (Reception is performed automatically at
midnight, 1:00, 2:00, 3:00 and 4:00 each morning.)
• Manual receive (You initiate reception using a button
operation.)
• If reception is not successful for any of the normal auto receive
operations shown above, auto receive is performed one more
time at 5:00 a.m.
• The watch is set up for auto receive at the factory, so all you need to
do is to place it in a location that allows good reception each night.
❚ To position the watch for optimum reception
Remove the watch from your wrist and place it somewhere so its
top (12 o'clock side, where the antenna is located) is facing
approximately in the direction of the signal transmitter. Keep the
watch away from metal objects.
Resin band
Metal band
• Orienting the watch so it is sideways to the transmitter makes it
more difficult to receive the signal.
• Do not move the watch while it is receiving the calibration signal.
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