70 Keysight NFA Series Noise Figure Analyzers Service Guide
Instrument Messages
Introduction
Event and Condition Categories
The three categories of severity are described below, for both Events and 
Conditions.
Errors
Error messages appear when a requested operation has failed. (For example, 
“Detector not available”, “File not saved”.) Error messages are often generated 
during remote operation when an invalid programming command has been 
entered. (For example, “Undefined header”.) 
Some errors are conditions rather than single events. They exist for a period of 
time, so they have associated “Detected” and “Cleared” events. (For example, 
“LO Unlocked” or “External reference out of range”.)
Error messages appear in the Status Bar at the bottom of the display. A 
message remains until you press a key, or another message is displayed in its 
place.
Error messages are logged in the error queues. If the error is a condition, both 
the Detected and Cleared events are logged.
Warnings
Warning messages appear when a requested operation has completed 
successfully, but there are modifications and/or side effects. (For example, if 
you requested too high a stop frequency, then “Data out of range” is displayed 
and the analyzer sets itself to the highest available stop frequency.)
Some warnings are conditions rather than single events. They exist for a period 
of time, so they have a “Detected” event and a “Cleared” event. (For example, if 
you set the sweep time too fast for a measurement to meet the instrument 
specifications then the “Meas Uncal” message is displayed until you slow down 
the sweep time.)
Warning messages appear in the Status Bar at the bottom of the display. The 
message remains until you press a key, or another message is displayed in its 
place. 
Warnings are logged in the error queues. If the warning is a condition, both the 
Detected and Cleared event messages are logged.