Tektronix RSA6100A Series, Help Manual

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Pulsed RF > Common Controls for Pulsed RF Displays Levels Tab
Levels Tab
Use the Levels tab to set parameters that control the method and levels used to calculate some pulse values.
Setting
Description
100% Level Speci fi es the method used to determine the 100% level(s).
50% Level Speci fi es the method used to determine the 50% level on the pulse.
Rise/Fall Levels Select whether to use the 10% to 90% or 20% to 80% points (based on voltage level)
to de
fi ne the rise and fall times.
xxx
100% Level
Use the 100% Level settings to select the method used to determine the 100% level(s) used for calculating
pulse parameters, for example, Rise, Fall, and Width.
The Pulse Average Amplitude de fi nes the pulse top as the average of the values of all the points along
the pulse top. This average is used as the 100% level, from which the 10, 20, 50, 80 and 90% levels are
calculated. Pulse measurements are referenced against these various levels. For example, Rise is the time
between the 10 and 90% (or 20 and 80%) levels on the rising edge of the pulse. When the Pulse Average
Amplitude method is selected, the same 100% level is used for both rising and falling edges.
Because some RF pulse types have droop (a height difference between the beginning and ending points of
the pulse top), the 100% percent level on the rising edge may not be equal to the 100% level on the falling
edge. The Independent method of pulse point location is designed for pulses with different 100% levels
at their rising and falling edges. The Independent method calculates the 100% level for the rising edge
separately from the 100% level of the falling edge. As a result, the 10, 20, 50, 80 and 90% levels are also
different for the rising and falling edges, allowing for more accurate measurements on pulses with droop.
50% Level
Select Voltage to use -6 dB as the 50% point. Select Power to use -3 dB as the 50% level.
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RSA6100A Series Real-Time Spectrum Analyzers Help