Agilent Technologies X Series Manual page 240

Complex Spectrum Measurement
Marker To
Notes
Initial S/W Revision
240
Make the Marker Y value to the display reference value.
If the currently selected marker is not on when this key is pressed, it is turned
on at the center of the screen as a normal type marker, and its amplitude
applied to the reference value.
You must be in the IQ Analyzer (Basic) mode to use this command. Use
INSTrument:SELect to set the mode.
Prior to A.02.00