Tektronix RSA6100A Series, Руководство пользователя

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Controlling the Acquisition of Data > Using Triggers to
Capture Just What You Want > Triggering Mask Editor (Frequency Mask Trigger)
To create a new mask without using Auto draw:
Click the New button.
Changing a Mask
A mask is a collection of points speci fi ed by their frequency (de fi ned by their offset from the center
frequency) and their amplitude. You can change a mask by adding (or removing) points and editing points.
NOTE.
When placing points in the frequency mask, keep in mind that in most cases, the Frequency Mask
Trigger has a range of 80 dB below Reference Level. However, for values of Reference Level lower than
-50 dBm, this range decreases as the RefLevel decreases. The FMT range is also reduced when the
Acquisition Bandwidth contains frequencies near 0 Hz. In both these situations, the underlying reason the
trigger range is reduced is because the instrument is using various amounts of "digital gain" in addition to
hardware gain. You are not prevented from placing mask points outside the usable range of the instrument,
but at the time the mask is applied, the instrument adjusts its range. When the mask is adjusted, you can
see this in the Spectrum display and the Mask Editor. The mask’s shaded
fi ll shows the usable vertical
range. Points outside this range are shown, but will not cause a trigger.
Adding Points
To add a point to a mask:
RSA6100A Series Real-Time Spectrum Analyzers Help
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