Tektronix DPO2304SX, Printable Help

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A value is considered high if the channel input voltage is greater than the specified threshold voltage; a value is considered
low if the channel input voltage is less than the specified threshold voltage. Use the "don't care" selection for any channels
that will not be used as part of the pattern.
1. You can set the mode and holdoff for all standard trigger types. Refer to trigger mode and set holdoff to learn more about
trigger mode and holdoff.
Trigger on a video signal
Use the following procedure to detect and trigger on a video signal. This feature is only available on some instruments. Only
composite signal formats are supported. Graphic display formats such as RGB and VGA are not supported.
1. Push the front-panel Advanced button.
2. In the Trigger control window, Open the A Event tab.
3. Select Video from the Trigger Type drop-down list.
4. To specify which channel becomes the trigger source, click Source; then select a channel from the drop-down list.
5. Select a signal format from the Format drop-down list:
■ If using a preset format, click the Lines and Fields Autoset buttons to optimize the instrument for viewing the fields or
lines for your chosen format
■
If you select the Custom signal format, no Autoset options are available. You must set the Scan Type (Interlaced or
Progressive) and Scan Rate.
■
Custom scan rates enable you to trigger on nonbroadcast video signals that have unique scan rates. Select the scan
rate that includes your signal.
6. Select a value from the Trigger On drop-down list to specify where the trigger will occur on the video signal:
■ Field. Use the drop-down list to select either Odd, Even, or All.
■ All Lines. The trigger will occur on any and all lines.
■ Line #. Use the multipurpose knob or pop-up keypad to set the line number. Line numbers wrap when their limits are
reached. The range of line numbers depends on the format.
7. Specify the Holdoff from the drop-down list, By Time or By Fields, then use the multipurpose knob to change the value. If
setting a Custom format, only the By Time control is available.
8. Select the Polarity:
■ Normal. Generally triggers on negative polarity, since the sync pulse leading edge is negative for most standard
formats.
■ Inverted. Use when probing circuitry that inverts the video signal.
9. You can set the mode and holdoff for all standard trigger types. Refer to trigger mode and set holdoff to learn more about
trigger mode and holdoff.
Trigger on a communication signal
Use the following procedure to set up the instrument to trigger on a communication signal:
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. Comm triggers are not available on DPO70000SX instruments.
1. Push the front-panel Advanced button.
2. In the Trigger control window, Open the A Event tab.
How to ?
DPO70000SX, MSO/DPO70000DX, MSO/DPO70000C, DPO7000C, and MSO/DPO5000B Series 635