Preparing for Initial Use of Your New FieldFox  13 
  The temperature at which the following events occur is the average of the RF1, 
RF2, SB1, SB2 temperatures. These temperatures come from internal sensors 
embedded within FieldFox. 
Temperature Control Mode 
At approximately 73°C, the FieldFox enters Temperature Control mode by 
reducing display intensity, switching to Outdoor Sun display colors, and 
reducing measurement speed. This should decrease the internal temperature 
which preserves measurement accuracy and maintains the long-term reliability 
of the FieldFox. When this occurs, the following message is displayed on the 
FieldFox screen: 
The system is entering Temperature Control Mode due to high internal 
temperature.  
When entering Temperature Control mode, save your instrument state and data 
that you want to keep.  
When the temperature drops to approximately 71°C, a message is displayed 
indicating that the FieldFox is leaving Temperature Control Mode and normal 
operating settings are restored. 
NOTE  Measurement speed specifications do NOT apply in Temperature Control Mode. 
High-Temp Shutdown 
In extreme situations, Temperature Control mode may not stop an increase in 
the FieldFox internal temperature.  At approximately 75°C, High-Temperature 
Shutdown will engage and turn OFF the FieldFox.  
Just prior to shutdown, the FieldFox will display a warning of imminent shut 
down.  
Avoid Overpowering the FieldFox 
The FieldFox can be damaged with too much power or voltage applied. 
Exceeding the maximum RF power levels shown below will cause an ADC Over 
Range message to appear on the screen.  
Maximum Input Voltages and Power: 
  RF IN/OUT Connectors: ±50 VDC, +27 dBm RF 
  DC Input: 19 to 19 VDC, 40 Watts maximum when charging battery 
 
Learn more about Maximum power and voltages in the 
FieldFox Data Sheet on page 214. 
 
NOTE  Very often, coaxial cables and antennas build up a static charge, which, if 
allowed to discharge by connecting to the FieldFox, may damage the instrument 
input circuitry. To avoid such damage, it is recommended to dissipate any static 
charges by temporarily attaching a short to the cable or antenna prior to 
attaching to the FieldFox.