The Hot Buzzer sounds from the speaker of W42H even when you have
Casio flat-type stereo earphones 03/flat-type switched earphone
microphone (option)/flat-type stereo earphone-microphone (option)
attached to your W42H.
Extension Mode
Using the extension mode, W42H automatically shuts down the radio
wave after issuing the Low Battery Alert. This is quite a useful function
that you can still check Outgoing/Incoming Records, Content of e-mail,
Address Book, Schedule and so on when necessary. In this case, you
can only use the functions which needs no radio wave.
■ To turn on Extension Mode
While the standby screen is displayed,
press c5341.
Display example when you switch to Extension Mode
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