Keysight N9927-90001 User’s Guide                29
Preparing for Initial Use of Your New FieldFox
FieldFox ON/OFF Settings
— On the battery. Open the FieldFox battery compartment door to view the 
battery LCD.
To conserve battery power:
—Use Run/Hold to single-trigger a measurement when needed. Hold is 
shown on the display.
—Press System
 then Display then Brightness. Use the   arrows, the 
rotary knob, or numeric keypad to adjust the brightness to dim the FieldFox 
display as much as possible.
— Briefly press the power button > Standby, to switch to Standby mode when 
the FieldFox is not being used.
 Press power button again to restore power. All 
current settings are preserved.
To recharge a battery:
Use ONLY a FieldFox charger to recharge a battery.
— The battery can be fully charged while in the FieldFox in about 4 hours with 
the FieldFox either ON or OFF.
— The battery can be fully charged externally using the external battery 
charger in about 4 hours.
— When the battery is removed, the FieldFox can still be powered by the 
AC/DC adapter.
FieldFox ON/OFF Settings
—To turn power ON, briefly press the power button. Boot-up takes about 1 
minute.
—To switch to Standby mode (low battery drain), briefly press the power 
button. See the Note above concerning Stand By.
When powered by the battery only, the FieldFox can stay in Standby mode 
for a maximum of four hours and then it powers off automatically. When 
the relative battery charge drops by about 20%, the FieldFox will power off 
to preserve the remaining charge.
The FieldFox power button shut down/standby sequence includes a 10 
second counter that allows you to either choose a softkey to immediately 
initiate the action
 (Standby / Shut down / Restart*), or to let the countdown 
counter expire after 10 seconds then perform the action. *Restart can only 
be enabled via the Restart softkey.