Agilent Technologies N9913A User Manual page 101

All three trigger types can be used in either Zero Span (time domain) or FFT
frequency sweeps. Learn more about Zero Span on page 99. Learn more about
FFT on page 97 .
FFT Gating is available for non-zero span measurements. Learn more about FFT
Gating on page 104.
Trigger Type
 Press Sweep 3
 Then
 Then
 Then choose from the following:
The following two selections are similar in that they both a trigger a sweep from
a signal at the SA RF Input connector. Experiment with both selections to find
the best trigger type for your application.
Trigger Slope
Trigger Slope determines which edge of an External, Video, or RF Burst trigger
signal initiates a sweep.
 Press Sweep 3
 Then
 Then
 Then choose from the following:
Trigger Delay
After a valid trigger signal is received, the sweep begins after the specified
Trigger Delay time.
To see the rising edge of a repetitive signal which is triggered on that edge, enter
a negative trigger delay value (also known as pre-trigger). Adjust the sweep time
to include the pre-trigger time.
SA (Spectrum Analyzer) Mode
Trigger Settings
Trig Type
Triggering is provided by the FieldFox internal circuitry. A new
Free Run
o
sweep begins when the previous sweep ends.
External A sweep is triggered on an external TTL signal at the Ref In/Trig
o
In connector on the FieldFox top panel. Choose to trigger on the rising slope
at about 1.7 V or on the falling slope at about 1.0 V using the Trigger Slope
setting (below).
Video A sweep is initiated when the displayed amplitude of an incoming
o
signal crosses the settable Trigger Level. This selection can detect low-
amplitude signals, but also has been filtered considerably and may not be a
true representation of the incoming signal.
A sweep is initiated when the signal at the third IF (analog) stage
RF Burst
o
crosses the settable Trigger Level. This selection offers a wider bandwidth
and may be a better representation of the incoming signal than Video trigger.
However, RF Burst is not as sensitive to triggering on low-level signals.
Trigger Settings
Trig Slope
Sweep is triggered by the rising (positive) edge of signal.
Pos
o
Sweep is triggered by the falling (negative) edge of signal.
Neg
o
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