Tektronix DPO2304SX, Печатная инструкция

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Serial mask testing option
Some instruments require mask testing options:
■ Install Option MTM on DPO7000C and MSO/DPO5000B Series instruments.
■ Install Option MTH on MSO70000C/DX and DPO70000C/DX Series instruments.
Select a mask type
From the Mask menu, select Mask Setup; then open the Masks tab.
Overview. Use the Type controls to choose a mask. Use the standard drop-down list to select a standard for the mask test. The
Mask Polarity control will appear, depending on the standard selected. Use the Mask Polarity controls to choose whether to test
the positive pulse, negative pulse, or both.
NOTE. The Comm Trigger is designed to work with communications mask and standard testing. Mask testing automatically uses
Communication triggers. You must install the Serial Communications Mask Testing Option on some instruments before you can
access the Comm triggers. DPO70000SX instruments only have the User Mask type.
To use.
1. Click one of the Type controls to select the mask type.
2. Click More for additional selections.
3. Click the standard drop-down list to select the mask standard.
4. If the Mask Polarity control is displayed, click it to select positive or negative.
Behavior. The type of mask you choose will determine which standards are available from the standard drop-down list. The
standard selected will determine whether the Mask Polarity control is displayed.
NOTE. For some masks, you may see a pop-up message that reads, "Consider System Bandwidth when testing at this bit rate."
This message appears if the bandwidth of the measurement system falls below 1.5 – 1.8 times the bit rate of the data signal.
Because the T11 committee has published a strict rule of 1.8 times the bit rate for electrical standards, be aware that useful
qualitative information can be gathered at the current system bandwidth but quantitative rise-time measurements may not be
reliable. A Consider System Bandwidth message will appear for all optical standards, since optical filtering is not available.
Alternatively, you can select Edge Setup from the Trigger menu to improve the stability.
What do you want to do next?
Learn about the Mask Display control window.
Learn more about mask alignment.
Go to the Mask Setup control window.
Mask testing setups
218 DPO70000SX, MSO/DPO70000DX, MSO/DPO70000C, DPO7000C, and MSO/DPO5000B Series