Keysight Technologies FieldFox N9912A104 User Manual page 249

Data Analysis Features
All about Markers
Figure 16-4 S21 of a filter with BW Markers and associated readout values. The search
criteria is -3 dB.
Figure 16-5 S11 of the same filter with same search criteria: -3 dB.
The same values would result from a search criteria of approximately +30.4
dB.
Keysight N9912-90001 User's Guide
——Negative values search down from the TOP (MAX) of the
response.
——Positive values search up from the BOTTOM (MIN) of the
notch.
——If you first enter Negative, then Positive values, it may be
necessary to press Marker, then More, then Markers All Off.
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