General Precautions; About The Power Supply - Casio SF-4990 User Manual

General Precautions

•
Never try to take the SF Unit apart.
•
Avoid strong impact and sudden temperature changes.
•
At very low temperatures, the display response time may slow down or the
display may fail completely. This is temporary and correct operation should
return at normal temperature.
•
To avoid serious damage to the SF Unit caused by leaking batteries, replace
batteries once every two years, regardless of how much you use the SF Unit
during that time.
•
Never use thinner, benzine or other volatile agents to clean the exterior of the
SF Unit. Instead, wipe it off with a soft cloth dampened in a solution of water
and a mild, neutral detergent. Wring the cloth out until it is almost dry.
•
If the SF Unit is exposed to strong electrostatic charge, the display may dim
or the SF Unit may lock up. To correct this situation, switch power off, and then
remove and then replace the batteries.
•
Do not press the keys with a pen, pencil or other sharp object.
•
The SF Unit may cause interference with radio or television reception. Keep
it away from such appliances when you are using it.
Leaving the backlight on for long periods greatly reduces battery life!

About the Power Supply

The SF Unit is powered by two CR2032 lithium batteries. Replace batteries as
soon as possible after low battery power is indicated by any of the following.
•
Low battery message appears on the display
•
Blank display when power is turned on
•
Dim display figures even after display contrast is adjusted
•
Failure of the backlight to turn on
Caution
•
All data stored in memory is lost if you remove both batteries at the
same time.
•
Be sure that you keep a separate copy of all important data that you
store in the SF Unit.
About the Power Supply
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