Tektronix WCA200A, Руководство пользователя

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Trigger
WCA230A & WCA280A User Manual
3- 151
Level. Sets the trigger level. Available when the trigger mode is set to Triggered
and the source is Power or External. Table 3--23 shows the setting range.
Table 3- 23: Trigger level setting range
Trigger source Trigger level
Power (Span BW) --40 to 0 dBfs in 1 dBfs steps (in time domain)
External --1.5 to +1.5 V in 0.1 V steps
Hint for the Power trigger. An input signal is FFT-processed every frame
(= 1024 points). However, the displayed data is less than 1024 points (refer to
Relation between Frame, Bin, and Pixel on page 3--190). For example, 801 bins
are displayed when the span is 10 MHz. The Power trigger always observes one
whole frame (= 1024 points) to determine trigger generation. Note that, as shown
in Figure 3--103, any signal exceeding the trigger level outside the range of
10 MHz of span activates the Power trigger even if no signal exceeds the
trigger level within the range of 10 MHz of span.
10 MHz span (801 bins)
One frame = 1024 points (Power trigger detection range)
Trigger level
Figure 3- 103: Power trigger detection range
Define Mask... Option 02 only . Creates a trigger mask when the trigger mode is
set to Triggered and the source is set to Freq Mask. The trigger mask is created
in the spectrum view. Refer to page 3--165 for details on creating a trigger mask.