Icom IC-02A/AT/E Instruction Manual page 49

BACKUP BATTERY
The 1C-O2A/AT/E uses an advanced, highly reliable CPU which is a
complete, self-contained microprocessor. The purpose of the battery
is to provide power to the CPU so it retains all memory information
during power failures, or if the power pack is unplugged or turned
off.
The usual life of the lithium battery is approximately five years of
use. It is advisable to monitor the lithium battery carefully and
replace it if there are repeated cases of display malfunction.
NOTE: Battery replacement should be done by your nearest
ICOM Authorized Dealer or ICOM Service Center.
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