Module No. 3539

Time Adjustment

Your watch can obtain date and time information by connecting with a phone and by receiving time signals, which it uses to adjust its settings.

Important!

When you are on an aircraft or in any other location where radio signals may cause problems, enable the watch’s Airplane Mode to disable connection with your phone.

Referring to the information below, configure the time setting in accordance with the method that suits your own lifestyle.

Do you use a phone?

Time correction by connecting with your phone is recommended.

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Can you receive a time signal in your area?

While the watch’s Home Time City setting is one where a time signal can be received, the watch’s time and day settings can be adjusted in accordance with the signal.

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Other than the above.

If you are unable to connect with a phone and are unable to receive a time signal, you can perform watch button operations to adjust its time setting.

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Time Adjustment Using a Time Signal

Overview

The watch’s time and day settings can be configured in accordance with a received time calibration signal.

Important!

In order to make it possible for the current time setting to be adjusted correctly based on time calibration signal reception, you need to specify the time zone where you are using the watch.

If the watch was unable to connect with a phone even once for time correction during the previous day while connection with a phone is being used, it will automatically try to receive a time calibration signal.

Note

Areas where time calibration signal reception is supported are limited. When the watch is in an area where time calibration signal reception is not possible, connect with a phone to adjust time and day settings.

Appropriate Signal Reception Location

A time calibration signal can be received while the watch is near a window.

Position the watch so its 12 o’clock side is facing the window.

Keep metal objects away from the watch.

Do not move the watch.

Do not perform any operation on the watch.

img_reception

Note

You may experience time calibration signal reception problems in the areas described below.

Among or near buildings

While riding in a vehicle

Near household appliances, office machines, mobile phones, etc.

On a construction site, in an airport, or any other location where radio wave interference occurs

Near high-voltage lines

In mountainous areas or behind a mountain

Time Signal Reception Ranges

Japan (JJY)

The Japan time signal radio stations are located on Mt. Otakadoya in Fukushima and Mt. Hagane in Fukuoka/Saga.
The reception range of the Japanese time signals is approximately 1,000 km from each transmission station.

China (BPC)

The China time signal radio station is located in Shangqiu, Henan Province, China.
The reception range of the Chinese time signal is approximately 1,500 km from the transmission station.

United States (WWVB)

The United States time signal radio station is located in Fort Collins, Colorado.
The reception range of the U.S. time signal is approximately 3,000 km from the transmission station.

U.K. (MSF)/Germany (DCF77)

The U.K. time signal radio station is located in Anthorn, Cumbria.
The German time signal radio station is located in Mainflingen, southeast of Frankfurt.
The reception range of the U.K. and German time signals is approximately 1,500 km from each transmission station.

Note

Even if you are within the normal reception range of a time calibration signal, reception may be made impossible by the following factors: geographic contours, weather, the season, the time of day, wireless noise.

A time calibration signal cannot be received while the city selected as your Home City is one that does not support signal reception.

Auto Time Calibration Signal Receive

An automatic time calibration signal receive operation is performed and the time and day settings are corrected between midnight and 5:00 a.m. Once a signal receive operation is successful, no more auto receive operations are performed that day.

  1. Place the watch near a window or some other location appropriate for signal reception.

  2. [RCVD] flashes while time signal reception is in progress.

    When the receive operation is successful, the time and day settings are corrected automatically, and the [RCVD] indicator appears.

Note

Reception takes anywhere from about two minutes to about 10 minutes. It can take as long as 20 minutes.

Manual Time Calibration Signal Receive

  1. Place the watch near a window or some other location appropriate for time signal reception.

  2. Enter the Timekeeping Mode.

  3. Hold down (D) for at least two seconds until [RCVD] flashes.

  4. This indicates that the receive operation has started. After the receive operation is complete, the watch’s time and day settings will be corrected accordingly.

    3539_RCVDmark

    The level indicator shows the signal level ([L1], [L2], [L3]) while a receive operation is in progress.

Note

When a receive operation is successful, [RCVD] will appear, and the time and day settings will be adjusted automatically.

If a receive operation fails for some reason, [RCVD] disappears and [NG] appears on the display. To return to the unadjusted timekeeping display, press any button.

The receive operation takes anywhere from about two minutes to about 10 minutes. It can take as long as 20 minutes.

Time calibration signal reception is better at night than during the day.

Receive Level Indicator

While a receive operation is in progress, its current status is indicated on the display as shown below. Use the level indicator to find a location where signal reception is stable.

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Note

It takes about 10 seconds for time signal reception conditions to stabilize.

Reception conditions are affected by weather, the time of day, the surrounding environment, etc.

Signal Reception Precautions

When the watch is unable to adjust its time in accordance with a calibration signal for some reason, average timekeeping accuracy is within ±15 seconds per month.

Note that an internal decoding process the watch performs after it receives a signal may cause the time setting to be slightly off (by less than one second).

Time calibration signal reception is not possible under the conditions described below.

While battery power is low

While the watch is in the Stopwatch Mode, Timer Mode, or Alarm Mode

When the watch is at Level 2 power saving

While a timer countdown operation is in progress

While auto time adjustment is disabled

While the Home City area setting is one where time signal reception is not possible

While the watch is outside the time signal reception range

When the receive operation is successful, the time and/or day settings will be corrected automatically. Summer time will not be applied correctly in the case described below.

When the summer time start date and time, end date and time, or other rules are changed by authorities

As of July 2022, China does not observe summer time. If China starts to observe summer time in the future, the time displayed by the watch for China may not be correct.

Using Watch Operations to Adjust the Time Setting

If your watch cannot connect with a phone for some reason, you can use watch operations to adjust date and time settings.

Setting a Home City

Use the procedure in this section to select a city to use as your Home City. If you are in an area that observes summer time, you can also configure a summer time setting.

Note

The initial factory default summer time setting for all cities is [AUTO]. In many cases, the [AUTO] setting lets you use the watch without switching between summer time and standard time.

  1. Enter the Timekeeping Mode.

  2. Hold down (A) for at least two seconds. Release the button when the name of the currently selected Home City appears on the display.

  3. 3539_fl_HT_SET_comon
  4. Use (B) and (D) to change the Home City setting.

  5. Holding down (B) or (D) scrolls through settings at high speed.

    For details refer to the information below.

  6. Press (C).

  7. Use (D) to select a summer time setting.

  8. Each press of (D) cycles through available settings in the sequence shown below.

    [AUTO]
    The watch switches between standard time and summer time automatically.

    [OFF]
    The watch always indicates standard time.

    [ON]
    The watch always indicates summer time.

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  9. Press (A) to complete the setting operation.

Note

While the setting is being configured, the watch will exit the setting operation automatically after about two or three minutes of non-operation.

Setting the Time/Date

  1. Enter the Timekeeping Mode.

  2. Hold down (A) for at least two seconds. Release the button when the name of the currently selected Home City appears on the display.

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  4. Keep pressing (C) until the setting you want to change is flashing.

  5. Each press of (C) moves the flashing to the next setting in the sequence shown below.

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  6. Configure the date and time settings.

  7. To reset the seconds to 00: Press (D). 1 is added to the minutes when the current count is between 30 and 59 seconds.

    For all the other settings, use (B) and (D) to change the flashing setting.
    Holding down (B) or (D) scrolls through settings at high speed.

  8. Repeat steps 3 and 4 to select time and date settings.

  9. Press (A) to complete the setting operation.

Note

While the setting is being configured, the watch will exit the setting operation automatically after about two or three minutes of non-operation.

Switching between 12-hour and 24-hour Timekeeping

You can specify either 12-hour format or 24-hour format for the time display.

  1. Enter the Timekeeping Mode.

  2. Hold down (A) for at least two seconds. Release the button when the name of the currently selected Home City appears on the display.

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  4. Press (C) eight times.

  5. This causes [12H] or [24H] to flash on the display.

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  6. Press (D) to toggle the setting between [12H] (12-hour timekeeping) and [24H] (24-hour timekeeping).

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  8. Press (A) to complete the setting operation.

Note

While the setting is being configured, the watch will exit the setting operation automatically after about two or three minutes of non-operation.

Using the Watch in a Medical Facility or Aircraft

Whenever you are in a hospital, on an aircraft, or in any other location where auto time calibration signal receive or connection with a phone may cause problems, you can perform the procedure below to disable such operations. To re-enable auto time adjustment, perform the same operation again.

  1. Enter the Timekeeping Mode.

  2. Hold down (A) for at least two seconds. Release the button when the name of the currently selected Home City appears on the display.

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  4. Press (C) 13 times.

  5. This displays [RECEIVING].

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  6. Press (D) to toggle between the auto time adjustment settings.

  7. [OFF]: Auto time adjustment disabled.

    [On]: Enable auto time adjustment.

  8. Press (A) to complete the setting operation.

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