Tektronix RSA7100 Series, Быстрый старт Руководство пользователя

Страница: 85 / 104

Operation
Minimum off time between trigger events and pulse width.
The minimum off time is the length of time for which
trigger conditions must be absent between the end of one trigger event and the start of the next trigger event to ensure
that the end of the
fi rst event is recognized. It is the same as the minimum pulse width. For example, if the minimum off
time is 34 ns and the time difference between pulses is 10 ns, then the data would show one pulse instead of two pulses
(assuming no trigger violations occurred).
Sample rate Minimum pulse width Minimum off time
15.6 MS/s 64 ns 64 ns
31.2 MS/s 32 ns 32 ns
62.5 MS/s
16 ns 16 ns
75.0 MS/s
27 ns 27 ns
150 MS/s
21 ns 21 ns
250 MS/s
20 ns 20 ns
500 MS/s 34 ns 34 ns
1 GS/s 34 ns 34 ns
Detectable triggers per second.
The analyzer can acquire up to 100,000 triggers per second. However, to ensure no
missed data, keep triggers to ≤ 10,000 triggers per second. As the number of triggers increases, processing speed will slow.
Set up a DPX Density trigger
The DPX Density trigger enables you to capture transient events that may be partially obscured by other higher-amplitude
or more frequent signals. If you can see it in the DPX bitmap, you can trigger on it. The DPX Density area measurement
is used to select the region of interest in the display and to measure its current density. You set a density threshold, and
the instrument triggers when the density measurement exceeds your threshold.
The quickest way to set up a DPX Density trigger is to use a mouse and right-click on a signal of interest in the DPX
graph, or press on the screen and hold with your
fi nger for one second. A menu will pop up. Select Trigger On This .
This action performs several tasks:
Places the density measurement box at the click point
Sets the measurement box to its default size
Measures the average density in the box
Sets the Trigger mode to Triggered
Selects the DPX Density "Higher" trigger type
Adjusts the trigger threshold to a density value slightly below the current measured value
Starts the acquisition process
You can also trigger acquisitions based on the density of the DPX Bitmap trace as follows:
1. Select Triggered mode in the Trigger control panel.
2. Select RF Input from the Source drop-down list.
RSA7100 Series Quick Start User Manual 65