Tektronix SPECMON3 Manual page 37

Operating Your Instrument
1. Select File > More presets > Application. Click OK.
2. Set the Center Frequency control to the carrier frequency of your pulsed signal.
3. Set the Reference Level to place the peak of the pulse signal approximately 0-10 dB down from
the top of the Time Overview display.
You may need to trigger on the signal to get a more stable display. This is set up in the Trigger control
panel. ("Trig" button). Using the Power trigger type with the RF Input source works well for many
pulsed signals.
4. Set the Analysis Period to cover the number of pulses in your signal that you want to analyze. To do
this, click in the data entry field of the Time Overview window and set the analysis length as needed.
Spectrum Analysis
The Spectrum Analysis application preset opens a Spectrum display and sets several parameters. The
Spectrum Analysis preset sets the analyzer as follows.
Spectrum Analysis : Sets the frequency range to maximum for the analyzer, and sets the RF/IF
optimization to Minimize Sweep Time.
To use the Spectrum Analysis preset (assuming that Spectrum Analysis is the selected preset on the list of
Application Presets and Preset action is set to Recall selected preset):
1. Select File > More Presets > Application.
2. Set the measurement frequency using the front-panel knob or keypad.
3. Adjust the span to show the necessary detail.
Time-Frequency Analysis
The Time-Frequency Analysis application preset opens the following displays:
Time Overview: Shows a time-domain view of the analysis time 'window'.
Spectrogram: Shows a three-dimensional view of the signal where the X-axis represents frequency,
the Y-axis represents time, and color represents amplitude.
Frequency vs. Time: This display's graph plots changes in frequency over time and allows you to
make marker measurements of settling times, frequency hops, and other frequency transients.
Spectrum: Shows a spectrum view of the signal. The only trace showing in the Spectrum graph
after selecting the Time-Frequency Analysis preset is the Spectrogram trace. This is the trace from
the Spectrogram display that is selected by the active marker. Stop acquisitions with the Run button
because its easier to work with stable results. In the Spectrogram display, move a marker up or down
to see the spectrum trace at various points in time.
The analysis period is set to 5 ms.
To use the Time-Frequency Analysis preset (assuming that Time-Frequency Analysis is the selected preset
on the list of Application Presets and Preset action is set to Recall selected preset):
SPECMON3 & SPECMON6 Printable Help
Presets
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