Korg TMR-50 Owner's Manual page 7

Do not mix partially used batteries with
new ones, and do not mix batteries of
differing types.
When the batteries run down, a battery symbol
will appear on the left side of the display.
When the batteries run down even further,
the battery symbol will blink. At this time, it
will no longer be possible to use the recorder
function to record. Although you will still be
able to play back recorded data and use the
tuner and metronome functions, you should
replace the batteries as soon as possible.
Setting the battery type
In order to get accurate readings of the
remaining battery power, select the type of
battery that's being used.
1.
When you replace the batteries and turn
on the power, the display will show a
screen allowing you to specify the type
of batteries you're using.
Battery type
2.
Press the TAP TEMPO button to select
the battery type.
AL: When using alkaline or zinc-carbon
batteries
nH: When using nickel-metal hydride
batteries
3.
Press the button.
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