Casio 2869, 2870 Reference, Auto Return Features, Scrolling, Initial Screens, Radio-controlledTimekeeping Precautions, Timekeeping, Power Saving Function, Backlight Precautions

Operation Guide 2869 2870

Reference

This section contains more detailed and technical information about watch operation. It also contains important precautions and notes about the various features and functions of this watch.

Auto Return Features

•If you leave the watch in the Time Recorder Mode or Alarm Mode for two or three minutes without performing any operation, it automatically changes to the Timekeeping Mode.

•If you leave a screen with flashing digits on the display for two or three minutes without performing any operation, the watch automatically exits the setting screen.

Scrolling

The B and D buttons are used in various modes and setting screens to scroll through data on the display. In most cases, holding down these buttons during a scroll operation scrolls through the data at high speed.

Initial Screens

When you enter the World Time or Alarm Mode, the data you were viewing when you last exited the mode appears first.

Radio-controlled Timekeeping Precautions

•Strong electrostatic charge can result in the wrong time being set.

•Even when the watch is within the reception range of the transmitter, signal reception is impossible if the signal is blocked by mountains or other geological formations between the watch and signal source.

•Signal reception is affected by weather, atmospheric conditions, and seasonal changes.

•The time calibration signal is bounced off the ionosphere. Because of this, such factors as changes in the reflectivity of the ionosphere, as well as movement of the ionosphere to higher altitudes due to seasonal atmospheric changes or the time of day may change the reception range of the signal and make reception temporarily impossible.

•Even if the time calibration signal is received properly, certain conditions can cause the time setting to be off by up to one second.

•The current time setting in accordance with the time calibration signal takes priority over any time settings you make.

•The watch is designed to automatically update the date and day of the week for the period January 1, 2000 to December 31, 2099. Setting of the date by the time calibration signal cannot be performed starting from January 1, 2100.

•This watch can receive signals that differentiate between leap years and non-leap years.

•Though this watch is designed to receive both time data (hour, minutes, seconds) and date data (year, month, day), certain signal conditions can limit reception to time data only.

•Normally, the signal reception date shown by the Last Signal screen is the date data included in the received time calibration signal. When only time data is received, however, the Last Signal screen shows date as kept in the Timekeeping Mode at the time of signal reception.

•If you are in an area where proper time calibration signal reception is impossible, the watch keeps time within ±15 seconds a month at normal temperature.

•If you have problems with proper time calibration signal reception or if the time setting is wrong after signal reception, check your transmitter, current city code, and DST (summer time) settings. The following are the initial factory defaults for these settings.

Setting	Initial Factory Default
Transmitter	qvtA
City code	BER (Berlin) (Module 2869)
	LON (London) (Module 2870)
DST	AUtO DST (Auto switching)
(summer time)
	2869	• To find out the module number of your watch, look at its
		back cover. The Module number (2869 or 2870) will be
		engraved inside the box on the back cover.

Transmitters

This watch is designed to receive the time calibration signal transmitted from Rugby, England and the signal from Mainflingen, Germany. You can select either one of the transmitters, or you can configure the watch to automatically select the transmitter that has the strongest signal.

•The following explains how the watch determines which transmitter it should check first while the watch is configured for auto transmitter search.

Module 2869

In this case:	The watch does this:
The first signal auto search operation	1. Checks the Mainflingen signal first.
after factory default settings are in effect,	2. If the Mainflingen signal cannot be
or after the city code has been changed.	received, checks the Rugby signal.
Any case other than the above.	1. Checks the last successfully received
	signal first.
	2. If the last successfully received signal
	cannot be received, checks the other
	signal.
Module 2870
In this case:	The watch does this:
The first signal auto search operation	1. Checks the Rugby signal first.
after factory default settings are in effect,	2. If the Rugby signal cannot be received,
or after the city code has been changed.	checks the Mainflingen signal.
Any case other than the above.	1. Checks the last successfully received
	signal first.
	2. If the last successfully received signal
	cannot be received, checks the other
	signal.

•Time calibration auto receive is turned on whenever the transmitter mode is qvtA, DCF or MSF. Auto receive is off whenever the transmitter mode setting is OFF.

•See “To select the transmitter mode” below.

•Since the watch checks signals from both transmitters when qvtA is selected as the transmitter mode, the signal receive operation can take as long as 12 minutes.

To select the transmitter mode

							1. In the Timekeeping Mode, hold down A until the city
		l		l ll			code setting starts to flash, which indicates the setting
							screen.
						l
	l					l
	l
		l			l	l	2. Press Cto display the transmitter mode setting screen.
l ll			l
l			l				3. Use Dto scroll through available transmitter modes
l					l
l
l	l l	l	l		l		until the one you want to select is displayed.
To do this:								Select this transmitter mode:
Automatically select the Rugby or Mainflingen signal								qvtA
Receive the Mainflingen signal								DCF
Receive the Rugby signal								MSF
Turn off auto receive								OFF

•Note that OFF appears in place of the transmitter mode indicator when any city code besides LON, PAR, BER, or ATH is selected as the Home City code. This indicates that you cannot specify a transmitter.

4.Press A twice to exit the setting screen.

Timekeeping

•Resetting the seconds to 00 while the current count is in the range of 30 to 59 causes the minutes to be increased by 1. In the range of 00 to 29, the seconds are reset to 00 without changing the minutes.

•The day of the week is automatically displayed in accordance with the date (year, month, and day) settings.

•The year can be set in the range of 2000 to 2099.

•The watch’s built-in full automatic calendar makes allowances for different month lengths and leap years. Once you set the date, there should be no reason to change it except after you have the watch’s battery replaced or when battery power drops to Level 4.

•The current time for all city codes in the Timekeeping Mode and World Time Mode is calculated in accordance with the Greenwich Mean Time (GMT) differential for each city, based on your Home City time setting.

•GMT differential is calculated by this watch based on Universal Time Coordinated

(UTC*) data.

*The letters “UTC” stands for “Universal Time Coordinated”, which is the world-wide scientific standard of timekeeping. It is based upon carefully maintained atomic (cesium) clocks that keep time accurately to within microseconds. Leap seconds are added or subtracted as necessary to keep UTC in sync with the Earth’s rotation. The reference point for UTC is Greenwich, England.

12-hour/24-hour Timekeeping Formats

The 12-hour/24-hour timekeeping format you select in the Timekeeping Mode is also applied in all other modes.

•With the 12-hour format, the P (PM) indicator appears on the display for times in the range of noon to 11:59 p.m. and the A (AM) indicator appears for times in the range of midnight to 11:59 a.m.

•With the 24-hour format, times are displayed in the range of 0:00 to 23:59, without any indicator.

Power Saving Function

When turned on, the Power Saving function automatically puts the watch into a sleep state whenever it is left for a certain period in an area where it is dark. The table below shows how watch functions are affected by the Power Saving function.

Elapsed Time		Display	Operation
in Dark
60 to 70 minutes	Blank, with Sleep indicator		All functions enabled, except
	(SLEEP	) flashing	for the display
6 or 7 days	Blank, with Sleep indicator		Beeper tone, backlight, display,
	(SLEEP	) not flashing	and auto receipt of the
			calibration signal are disabled.

•Wearing the watch inside the sleeve of clothing can cause it to enter the sleep state.

•The watch will not enter the sleep state while the Timekeeping Mode time is between 6:00 AM and 9:59 PM. If the watch is already in the sleep state when the time reaches 6:00 AM, however, it will remain in the sleep state.

•The watch will not enter the sleep state while it is in the Stopwatch Mode.

To recover from the sleep state

Perform any one of the following operations.

•Move the watch to a well-lit area. It can take up to two seconds for the display to turn on.

•Press any button.

•Angle the watch towards your face for reading.

To turn Power Saving on and off

						1. In the Timekeeping Mode, hold down A until the city
	ll					code setting starts to flash, which indicates the setting
l						screen.
		l
l		l				2. Press Aagain.
l
l		l		ll		3. Press Cseven times until the Power Saving on/off
	l	ll ll
		l			l	screen appears.
		l			l
		ll	l l l			4. Press Dto toggle Power Saving on (ON) and off
Power saving						(OFF).
						5. Press Ato exit the setting screen.
on indicator
						• The Power Saving on indicator (SAVE ) is on the
						display in all modes while the Power Saving is turned
						on.

Backlight Precautions

•The electro-luminescent panel that provides illumination loses power after very long use.

•The illumination provided by the backlight may be hard to see when viewed under direct sunlight.

•The watch may emit an audible sound whenever the display is illuminated. This is due to vibration of the EL panel used for illumination, and does not indicate malfunction.

•The backlight automatically turns off whenever an alarm sounds.

•Frequent use of the backlight shortens the battery operating time.

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