Agilent Technologies 8614 B Series User Manual page 111

Function Reference
Marker Setup
Peak Excursion
Determines (in dB) which side modes are included in the measurements. To be accepted, each
trace peak must rise, and then fall, by at least the peak excursion value about a given spectral
component. The default value is 3 dB. Setting the value too high may result in not identifying a
side mode. Setting the value too low may cause unwanted responses, including noise spikes, to
be identified. Use the Marker Setup panel to change the peak excursion value.
Peak excursion criteria
Changing the peak excursion. The peak searches may not recognize valid signals near the noise
floor when the peak excursion definition is less than 3 dB. Thus, before performing peak searches
on signals near the noise floor, reduce the peak excursion value. However, reducing the excur-
sion value often causes peak searches to identify noise spikes. To avoid this misidentification, use
video averaging or video filtering to reduce the noise floor variance to a value less than the peak
excursion definition.
Pit Excursion
Sets the pit excursion value for the marker search routines.
Pit excursion criteria
The pit excursion value is used to determine whether or not a local minimum in the trace is to be
considered a pit. To qualify as a pit, both sides of the local minimum must rise by at least the pit
excursion value.
Changing the pit excursion. The pit searches may not recognize valid signals near the noise floor
when the pit excursion definition is less than 3 dB. Thus, before performing pit searches on sig-
nals near the noise floor, reduce the pit excursion value. However, reducing the excursion value
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