Tektronix DPO2304SX, Printable Help

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Select the RS-232 data parity
In the Data Parity drop-down list, select the parity for the trigger.
Set the upper and lower threshold values
The upper and lower threshold levels define the voltage limits of a runt pulse.
■ To set the upper threshold, click in the Upper Level entry box, and then use the multipurpose knob to set the voltage level.
■ To set the lower threshold, click in the Lower Level entry box, and then use the other multipurpose knob to set the voltage
level.
Runt trigger criteria
■ Select Occurs from the Runt drop-down list to trigger on any runt.
■ Select Wider from the Runt drop-down list to trigger on a runt pulse of a minimum width; click in the Width entry box and use
the multipurpose knob to set the minimum pulse width.
■ Select Logic from the Trigger if Runt drop-down list to trigger on a logic-qualified runt pulse. When the instrument detects
that a runt has occurred, it checks the logical state of two other available channels and triggers only if their conditions are
met. Each channel can have a value of high (H), low (L), or "don't care" (X). 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 X "don't care" selection for any channels that will not be used as part of the pattern.
Save a mask
Use the Mask Edit Setup control window to save a mask:
1. From the Mask menu, select Mask Edit Setup.
2. In the Mask Edit control window, click Save.
3. In the Save As dialog box, select User Mask. You may need to click More to access the User Mask selection.
4. Enter a file name in the Name box. If you do not have a keyboard attached, click the keyboard icon to use the pop-up
keyboard to enter the file name.
5. Click Save to save the mask. The default folder for saving masks is
C:\Users\[Username]\Tektronix
\TekScope\Masks
. If you want to save the mask in a different folder, click the Save in drop-down list, and then click a
folder to select it.
Scallop loss
Scallop loss is the difference between the actual magnitude and the computed magnitude of a signal that is halfway between two
frequency bins in the spectral output data. Scallop loss is only noticeable when the spectral analyzer is not using zero-fill such as
when it is set to full span.
If zero-fill is in use, frequency domain interpolation occurs and there is minimal scallop loss. Zero-fill cannot be directly controlled;
it is affected by changing settings of resolution bandwidth or gate width. When in use, a minimum of 20% of the FFT input is
always zero, effectively removing scallop loss error by interpolating in the frequency domain.
NOTE. For most settings, descriptions of amplitude accuracy due to scallop loss (as discussed in other publications) do not apply
to this oscilloscope when used as a spectral analyzer because of zero-fill. Full span is the most likely setting where scallop loss
might occur.
Oscilloscope reference
820 DPO70000SX, MSO/DPO70000DX, MSO/DPO70000C, DPO7000C, and MSO/DPO5000B Series