Keysight NFA Series Noise Figure Analyzers Service Guide               341
Service and Diagnostics Menus
Service Key Descriptions
IF
Immediately executes an alignment of the IF subsystem. The 
instrument will stop any measurement currently underway, perform 
the alignment, then restart the measurement from the beginning.
A failure of IF will set the Error Condition “Align IF failed”. A failure will 
not employ new IF alignment data.
Successful completion of IF will clear the Error Condition “Align IF 
failed” and clear bit 6 in the Status.
The Advisory Event “Alignment complete” is displayed when the 
alignment is complete.
Align IF can be interrupted by pressing the Cancel (ESC) front-panel 
key. When this occurs, no new IF alignment data will be employed.