Casio 668 User manual

1
Operation Guide 668 2168 2505
MA0905-EC
About This Manual
•Button operations are indicated using the letters
shown in the illustration.
Stopwatch Mode Setting ScreenTimekeeping Mode Alarm Mode
Press B.
General Guide
••
••
•Press Bto change from mode to mode.
••
••
•Pressing Bafter performing some operations in any mode returns to the
Timekeeping Mode.
••
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•If you do not perform any operation for a few minutes in the Alarm Mode or
Setting Screen, the watch automatically reverts to the Timekeeping Mode.
Timekeeping Mode
In the Timekeeping Mode, press Cto switch between
the 12-hour and 24-hour formats.
••
••
•When the 12-hour format is selected, the indicator PM
appears on the display to indicate “P.M.” times. There
is no indicator for “A.M.” times.
••
••
•When the 24-hour format is selected, the indicator
24H appears on the display.
••
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•A charge indicator appears on the display of this
watch when charging is required.
To turn the Daily Alarm and Hourly Time Signal on and off
Press Cwhile in the Alarm Mode to change the status of the Daily Alarm and
Hourly Time Signal in the sequence shown below.
Hourly Time
Signal Only
Daily Alarm
Only
Both OFFBoth ON
••
••
•The alarm and hourly time signal indicator is displayed in all modes.
To test the alarm
Hold down Cwhile in the Alarm Mode to sound the alarm.
Stopwatch Mode
The Stopwatch Mode lets you measure elapsed time,
split times, and two finishes. The range of the
stopwatch is 59 minutes, 59.99 seconds.
Charge indicator
Hour
Minutes
Seconds
PM indicator
Day of week
Day
To set the time and date
1. Press Bthree times in the Timekeeping Mode to
display the setting screen.
2. Press Ato move the selection (flashing) in the
following sequence.
Seconds Hour Minutes
Day Month
Day of week
3. While the seconds setting is selected (flashing), press Cto reset it to 00. If you
press Cwhile the seconds setting is in the range of 30 to 59, the seconds are
reset to 00 and 1 is added to the minutes. If the seconds setting is in the range
of 00 to 29, the minutes count is unchanged.
4. While any other setting is selected (flashing), press Cto increase the number.
••
••
•Holding down Cchanges the setting at high speed.
5. After you set the time and date, press Bto return to the Timekeeping Mode.
Alarm Mode
When the Daily Alarm is turned on, the alarm sounds for
20 seconds at the preset time each day. When the
Hourly Time Signal is turned on, the watch beeps every
hour on the hour.
To set the alarm time
1. Press Awhile in the Alarm Mode. The hour digits
flash because they are
selected .
••
••
•At this time the alarm is automatically turned on.
Flashing
Hour
Minutes
Alarm on indicator
Hourly time signal on indicator
Mode indicator
2. Press Ato change the selection in the following sequence.
Daily Alarm and
Hourly Time Signal
on and off
Minutes
Hour
3. Press Cto increase the selected digits. Holding down Cchanges the number
at high speed.
••
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•The format (12-hour and 24-hour) of the alarm time matches the format you
select for normal timekeeping.
••
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•When setting the alarm time using the 12-hour format, take care to set the time
correctly as morning or afternoon.
To stop the alarm
••
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•Press Ato stop the alarm after it starts to sound.
Minutes
Seconds
1/100 second
Mode indicator
Elapsed time measurement
Start Stop Re-start Stop Clear
Start Split Split release Stop Clear
Start Split Stop Split release Clear
Split time measurement
Split time and 1st-2nd place times
First runner
finishes.
Display time of
first runner.
Second runner
finishes.
Display time of
second runner.
Power Requirements
This watch works by light energy, so no battery is necessary. Light energy is
converted into electric energy by solar cells and stored into the capacitor. Once
fully charged, the watch can continue to run for a number of days (Modules 668
and 2168: 4 days, Module 2505: 14 days) without being exposed to light.
■Charging light
••
••
•The watch will start to work within about two seconds after it is exposed to light
(such as general office illumination). Set the time and calendar at this time.
••
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•You can put on the watch after the “charge indicator ( )”disappears from the
display.
••
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•The beeper sound may be weak and the display may be dim while the charge
indicator is on the display.
••
••
•Use the information in the table below as a reference how long you need to
expose the watch to light when charging it.

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Operation Guide 668 2168 2505
Charging Time
••
••
•Note the following to ensure that your watch remains charged and running.
* Wear the watch outside your sleeve.
* Place the watch in a well-lit location when you are not wearing it.
Specifications
Accuracy at normal temperature: ±30 seconds a month
Timekeeping Mode: Hour, minutes, seconds, p.m. (PM), day of the week, day
Time system: Switchable between 12-hour and 24-hour formats
Calendar system: Auto-calendar set at 28 days for February
Alarm Mode: Daily alarm, hourly time signal
Stopwatch Mode: Measuring unit: 1/100 of a second
Measuring capacity: 59 minutes, 59.99 seconds
Measuring modes: Elapsed time, split time and two finishes
Charge Storage: Coin type capacitor
Days to Discharge: Modules 668 and 2168: 4 days
Module 2505: 14 days
(Above values are from full charge to stopping of watch
operation, based on 20 seconds of alarm and 24 Hourly
Time Signals per day.)
Conditions
Charging Time
(until charge indicator
disappears)
Minimum Daily
Charge
Maximum Charging
Time
Modules Module Modules Modules Module
668, 2168 2505 668, 2168, 2505 668, 2168 2505
Direct sunlight
(100,000 lux.) 15 min 45 min 4 min 40 min 2 hrs
At a sunny window
(20,000 lux.) 50 min 3 hrs 12 min 2 hrs 6 hrs
Fluorescent light
(5,000 lux.) 4 hrs 12 hrs 50 min ——
General office
illumination (700 lux.) —— 6 hrs ——