Operation Guide 2514/2645

How a Radio-controlled Watch Works

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.

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 using
Transmitter
Long-wave time
built-in antenna.

 

 

calibration signal
Watch decodes

 

 

Calibration Signal

• The Japanese calibration signal (Call Sign: JJY) is maintained by
the independent Japan Ministry of Posts and Telecommunications
Communication Research Laboratory (CRL). 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

•For information about selecting a Home City, see “To manually set the time and date”.

Home City
Transmitter

 

 

TYO
Either the Mt. Otakadoya signal (40kHz) or the Mt.Hagane signal (60kHz)

 

 

LAX, DEN, CHI, NYC
Fort Collins, Colorado signal

 

 

 

 

received data and

 

 

converts it to time

 

Signal data
data.

 

Decode

 

Cesium
Time data
Time is adjusted

 

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.

the National Institute of Standards and technology from Fort
Collins, Colorado.

Though the calibration signal is normally transmitted 24 hours a day, transmission may be interrupted occasionally due to maintenance, lightening, etc.

Transmitter Location
1000km
500km
Mt. Otakadoya
(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.

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.

•Geographic contours, nearby buildings, the season, 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.

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

Receiving the Calibration Signal

There are two methods you can use to receive the time calibration signal.

•Auto reception (Reception is performed automatically at 2:00, 4:00, and 6:00 each morning.)

•Manual receive (You initiate reception using a button operation.)

•The watch is set up for auto reception at the factory, so all you need to do is to place it in a location that allows good reception each night.

❚To make reception easier

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 it away from metal objects.

❚Time Required for Reception
Signal reception takes anywhere from about two to six minutes.

•Note that when “FREQ. AT” is specified as the frequency selection mode, signal reception can take up to 12 minutes.

•See “Specifying the Transmitter Mode” for more information.
❚To trigger reception manually
Hold down the A button for about two seconds.

• The watch beeps and reception starts. Ongoing reception is indicated by the “” icon and the receive indicator.

❚To stop signal reception
❚Receive Icon and Indicator
While reception is in progress, the

 

 

 

 

 

Receive Icon

“ ” icon and the receive indicator

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

cycle from “Unstable” through

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

“Stable” as shown below. How far

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

they cycle depends on the signal

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

strength.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Keep the watch in a location where

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

reception is stable while reception is

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

in progress.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Receive Indicator

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Inside a vehicle

(automobile, train, plane, etc.)

Next to a household appliance or office equipment (TV, speaker, fax, PC, mobile phone, etc.)

Resin band
Press the A button.
•All other buttons besides A are disabled during signal reception.

In a location where there is radio interference

(construction site, airport, etc.)

Near mountains

Metal band
When reception is successful

After reception is complete, the watch adjusts its current time setting and then its current date setting.

•The “” icon and the receive indicator remain on the display to indicate that reception was successful.

When reception fails

The watch does not adjust its current time setting, and displays “ERROR!” instead.

Unstable
Stable
• Even under optimum reception conditions, it can take about 10
seconds for reception to stabilize.
• Use the receive icon and receive indicator to check
reception status and to determine the best location for
signal reception.

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.

•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.

•The display will return to the normal timekeeping screen automatically if you do not perform any operation for about one or two minutes.

• Note that weather, the time of day, surroundings, and other
factors can all affect reception.

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