Casio 2645 User Manual

MA0310-EA

Power Saving

Operation Guide 2514/2645

The Power Saving feature of the watch is turned on at the factory.

• Power Saving causes the watch to automatically enter a sleep state to save power whenever the watch is left in the dark.

• Note that the watch may also enter the sleep state if the watch is blocked from light by your sleeve.

❚

How the sleep state works

• Display sleep state

The display sleep state is triggered whenever the watch is left in the dark for three or four days.

• The display goes blank, except for a sleep indicator. Alarms, the hourly time signal, and auto signal reception continue to operate normally while the watch is in the display sleep state.

• Function sleep state

The function sleep state is triggered whenever the watch is left in the dark for four days.

• Alarms, the hourly time signal, and auto signal reception do not operate while the watch is in the function sleep state.

• Digital timekeeping functions continue to operate normally in the function sleep state.

Each press of the C button sounds a confirmation tone and cycles through available modes in the sequence shown below.

• The watch will automatically revert to the Timekeeping Mode if you leave it in the Alarm Mode or Data Memory Mode without performing any operation for about two or three minutes.

Sleep indicator

❚

To recover from the sleep state

Move the watch to a brightly lit location or press any button.

• It may take as long as five seconds to recover from the sleep state

❚

To turn Power Saving on and off

See the procedure under “To manually set the time and date” for information about turning off Power Saving.

Leaving the watch in a drawer or anywhere else it is dark can cause Power Saving to trigger in order to conserve battery power.

World Time ModeTimekeeping Mode

(Light)

Button

(RECOVER indicator)

Button

(Sleep indicator)

Button

(Mode Switching)

Battery Indicator

day

Month

PM indicator (no display for AM)

Hour

Minutes

Button

(Alarm Indicator)

Day of the Week

Receive Icon

Receive Indicator

Seconds

Days of the Week

SUN : Sunday MON : Monday TUE : Tuesday WED : Wednesday THU : Thursday FRI : Friday SAT : Saturday

GMT Differential

World Time

Stopwatch Mode

Time

City Code

Mode Name

• The actual appearance of your watch display depends on its model number.

Alarm Mode

Alarm Number

Message text appears when text is present.

Alarm Time

Data Memory Mode

Data

Record Number

Display IlluminationModes and Display Screens

Pressing the L button in any mode illuminates the display for about 1.5 seconds for easy reading in the dark.

Important!

• The light may be difficult to see if you turn it on under bright sunlight.

• The light is shut off automatically if the alarm starts to sound while it is on.

• You may notice a slight sound from the watch while the display is illuminated. This is the sound of EL panel vibration, and does not indicate malfunction.

Operation Guide 2514/2645

Power Supply

The power supply of this watch uses a solar cell to generate electrical power, which is stored by a rechargeable battery. Using or storing the watch where it is not regularly exposed to light, or allowing it to be blocked from light by your sleeve as you are wearing it can cause the power of the rechargeable battery to run down. To ensure stable operation, be sure to allow the watch to be exposed to light as much as possible when you are wearing or storing it.

Note that all data in memory and all settings are cleared whenever you allow the level of the rechargeable battery to drop to Level 4.

Battery Indicator

Level 1

Level 2

Level 3

Level 4

• Exposing the watch to direct sunlight or other strong light may cause the battery level indicator to momentarily indicate a level that is higher than the actual battery level. Because of this, you should wait for a short while after charging to check the battery level indicator.

Normal operation enabled.

Signal reception, tones (alarms, hourly time signal) display illumination, digital display, and button operations disabled.

All functions, including digital timekeeping, disabled.

Important!

• Even after the battery drops to Level 4, watch operation will resume as soon as charging starts. However, you should wait until the battery reaches Level 2 before setting the time and date.

❚

Start charging at Level 3!

If the Level 3 indicator starts to flash, it means that battery power is very low. Be sure to expose the watch to light for recharging as soon as possible after the Level 3 indicator starts to flash.

❚

RECOVER Indicator

If you use the light or alarms a number of times during a short period, the RECOVER indicator may appear on the display to indicate that the following operations are disabled in order to allow battery power to recover.

• Display illumination

• Alarm and hourly time signal

• Time calibration signal reception

Normal operation will return after the battery recovers.

RECOVER indicator

World Time Mode

World time lets you display the current time in any one of 30 cities (29 time zones) around the world.

• When you enter the World Time Mode, the screen for the city that was displayed when you last exited the mode appears first.

• The seconds count in the World Time Mode is linked with the Timekeeping Mode seconds count.

• Selecting 24-hour timekeeping for the Timekeeping Mode automatically switches the World Time mode to 24-hour timekeeping.

Important!

If the World Time Mode time is incorrect, correct the setting of the current time in the Timekeeping Mode.

• See “To manually set the time and date” for more information.

❚

To search for a city

(Back)

D (+) and

In the World Time Mode, use the buttons to scroll through city codes.

• Holding down either button scrolls city codes at high speed.

City Code

GMT Differential

World Time

(Forward)

A (–)

Charging Precautions

Avoid charging the watch in the following locations, and anywhere else the watch may become very hot.

• On the dashboard of an automobile parked in the sun

• Very close to an incandescent light source or other sources of

heat

• In a location exposed to direct sunlight for long periods Note that the display panel may become black under very high temperatures. This is temporary, and the display will appear normal again at lower temperatures.

Depending on the light source you are using, the case of the watch may become quite hot during charging. Take care to guard against burn injury after charging.

❚

To charge the battery

Point the solar panel (face) of the watch at a light source.

• Remember that even a partial blockage of the solar cell reduced charging efficiency.

Example: Positioning the watch

Solar Cell

• The illustration shows the resin band mode.

Using Summer Time (DST)

Summer time, or Daylight Saving Time (DST) as is it is called in some countries, calls for setting clocks ahead one hour during the summer season. Note that the use of summer time depends on the country and even the local area.

❚

To turn summer time on and off

1. In the World Time Mode,

2. Press the

• The “DST” indicator appears on the display and

• You can turn summer time on or off independently for each

use the buttons to select the city whose summer time setting you want to change.

toggle auto reception ON and OFF.

timekeeping is advanced by one hour when summer time is turned on.

World Time Mode city. Note, however, that you cannot change the summer time setting for the “GMT” (Greenwich Mean Time) zone.

D and

B button to

DST indicator

❚

Charging Guide

Starting from a full charge, it should take approximately six months of operation without further charging under the conditions described below before battery drops to Level 3.

Daily Use (All time values are approximate.)

• Display Illumination: 1.5 seconds

• Alarms: 10 seconds

• Signal reception: 3 times

Making sure the watch is regularly exposed to light ensure stable operation.

• Charge Times Required to Advance to a Higher Level

Exposure Level

(Brightness)

Outdoor Sunlight

(50,000 lux)

Sunlight Through a

Window (10,000 lux)

Daylight Through a

Window on a Cloudy

Day (5,000 lux)

Indoor Fluorescent

Lighting (500 lux)

• Note that the above charging times are for reference only. Actual charging time depends on a variety of environmental factors.

Level 4 \ Level 3 \ Level 2 \ Level 1

Required Daily Charging Time

• The following is the daily amount of charging required each day to support the operations under “Daily Use”.

Exposure Level

(Brightness)

Outdoor Sunlight

(50,000 lux)

Sunlight Through a

Window (10,000 lux)

Daylight Through a

Window on a Cloudy Day

(5,000 lux)

Indoor Fluorescent

Lighting (500 lux)

Approximate Charging Time

52 min.

2 hr.

4 hr. –––

37 hr. –––

15 hr.

67 hr.

Approximate

Charging

Time

5 min.

24 min.

48 min.

8 hr.

2 hr.

13 hr.

–––

City Code List

City

GMT

–11 –10

–9 –8 –7 –6 –5 –4 –3 –2 –1 +0 +0 +1 +1 +2 +2

City Name

Honolulu

Anchorage

Los Angeles

Denver

Chicago

New York

Caracas

Rio de Janeiro

Greenwich Mean Time

London

Pari s

Berlin

Athens

Cairo

Code

Differential

–––

HNL

ANC

LAX

DEN

CHI NYC CCS

RIO ––– ––– GMT LON

PA R BER

AT H

CAI

• The contents of the above table are current as of June 2002.

• Time differentials in the above table are in accordance with

Universal Time Coordinated (UTC).

City

Code

JRS

JED THR DXB KBL

KHI DEL DAC

RGN

BKK HKG SEL TYO ADL SYD

NOU WLG

GMT

Differential

+2 +3

+3.5

+4.5

+5.5

+6.5

+7 +8 +9 +9

+9.5

+10 +11 +12

City Name

Jerusalem

Jeddah

Teheran

Dubai Kabul

Karachi

Delhi

Dakar

Yangon

Bangkok

Hong Kong

Seoul Tokyo

Adelaide

Sydney

Noumea

Wellington

Operation Guide 2514/2645

How a Radio-controlled Watch Works

What is a radio-controlled watch?

Yo ur 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

Cesium atomic clock

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.

Long-wave time calibration signal

Signal data

Time data

Watch

Internally

built-in antenna.

Decode

Watch decodes received data and converts it to time data.

Time is adjusted according to time data.

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

Inside a vehicle (automobile, train, plane, etc.)

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.

Near high-voltage lines

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

Near mountainsIn a location where there is radio

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 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.

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.

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.

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 “To manually set the time and date”.

Home City

TYO

LAX, DEN, CHI, NYC

Transmitter Location

Mt. Hagane (60kHz)

• 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, 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.

❚

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 about two seconds.

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

❚

To stop signal reception

Press the

• All other buttons besides A are disabled during signal reception.

500km

A button for

A button.

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

Fort Collins, Colorado signal

1000km

Mt. Otakadoya (40kHz)

500km

1000km

❚

While reception is in progress, the “ ” 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.

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.

• Even under optimum reception conditions, it can take about 10

When reception fails

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

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

Transmitter

Transmitter Location

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.

3000km

Receive Icon and Indicator

Receive Icon

Receive Indicator

Unstable Stable

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.

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

+ 4 hidden pages