Tektronix RSA6100A Series, Help Manual

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GP Digital Modulation > Common Controls for GP
Digital Modulation Displays Analysis Time Tab
The settings values on this tab are the same as those on the main Analysis control panel for the instrument
with the only difference being that Analysis Length can be set in either Seconds or Symbols in this location.
Setting Description
Analysis Offset Speci fi es the location of the fi rst time sample to use in measurements.
Auto When enabled, causes the instrument to set the Analysis Offset value based on the
requirements of the selected display.
Analysis Length Speci fi es the length of the analysis period to use in measurements. Length is speci fi ed in
either seconds or symbols, depending on the Units setting. For most modulation types,
the Analysis Length set when Auto is enabled is 128 symbols. For some modulation
types, a longer length is used.
Auto When enabled, causes the instrument to set the Analysis Length value based on the
requirements of the selected display.
Time Zero Reference Speci fi es the zero point for the analysis time.
Actual This is a displayed value, not a setting. It is the Analysis Length (time or symbols)
being used by the analyzer; this value may not match the Analysis Length requested
(in manual mode).
Units
Sets the units of the Analysis Length to either Symbols or Seconds.
xxx
Analysis Offset
Use analysis offset to specify where measurements begin. Be aware that you cannot set the Analysis
Offset outside the range of time covered by the current acquisition data. (all time values are relative
to the Time Zero Reference).
You can set the Analysis Length so that the requested analysis period falls partly or entirely outside the
current range of acquisition data settings. When the next acquisition is taken, its Acquisition Length will
be increased to cover the new Analysis Length, as long as the Sampling controls are set to Auto. If the
Sampling parameters are set to manual, or if the instrument is analyzing saved data, the actual analysis
length will be constrained by the available data length, but in most cases, measurements are able to be
made anyway. The instrument will display a noti
fi cation when measurement results are computed from
less data than requested. Range: 0 to [(end of acquisition) - Analysis Length)]. Resolution: 1 effective
sample (or symbol).
Analysis Length
Use the analysis length to specify how long a period of time is analyzed by a measurement. As you adjust
this value, the actual amount of time for Analysis Length, in Symbol or Seconds units, is shown below the
control in the "Actual" readout. This setting is not available when Auto is checked. Range: minimum
value depends on modulation type. Resolution: 1 symbol. A maximum of approximately 80,000 samples
can be analyzed (the actual value varies with modulation type).
Time Zero Reference
All time values are measured from this point (such as marker position or horizontal position (in Y vs Time
displays). Choices are: Acquisition Start or Trigger.
RSA6100A Series Real-Time Spectrum Analyzers Help
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