SUUNTO D9tx - Manual (Page 68)

If the battery symbol is displayed in the Surface mode, or if the display is faded or
weak, the battery may be too low to operate the dive computer, and battery replacement
is recommended.
NOTE
For safety reasons, the backlight cannot be activated when
the low battery warning is indicated by the battery symbol.
The optional wireless pressure transmitter sends out a low battery (batt) warning when
its battery voltage is getting low. This is shown intermittently instead of the pressure
reading. When you get this warning, the tank pressure transmitter's battery needs to
be replaced.
5.9.4. Diving at altitude
The dive computer can be adjusted both for diving at altitude and also to increase the
conservatism of the mathematical nitrogen model.
When programming the instrument for the correct altitude, you need to select the
correct Altitude Adjustment settings according to Table 5.6, Altitude Adjustment settings.
The dive computer will adjust its mathematical model according to the entered altitude
setting, giving shorter no-decompression times at higher altitudes.
For more information, see Section 10.2.3. Altitude diving.
Table 5.6. Altitude Adjustment settings
Altitude range Alt. adjustment
value
0–300 m / 0–1000 ft A0
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