Cable and Antenna Test Mode
R&S
®
Cable Rider ZPH
133
User Manual 1321.0950.02 ─ 03
If you have already selected a limit line, you can turn the limit line on and off with
the "Show Limit Lines" softkey.
Alternatively, you can define a threshold that works like a limit line. A threshold is a
simple horizontal limit line.
1. Press the "Upper Limit" or "Lower Limit" softkey.
2. Select the "Set Threshold" menu item.
The R&S Cable Rider ZPH opens an input field to define the threshold.
3. Enter the threshold you require.
The R&S Cable Rider ZPH displays the line and performs a limit check for that
threshold.
Threshold line and display line
Like the display line, a threshold line is a straight horizontal line. The difference is that
the R&S Cable Rider ZPH performs a limit check for threshold lines, but not for display
lines.
A failed limit check may be an issue if you want to create a measurement report,
because measurements with failed limits are not included in this report.
Using a display line, you can use a line and are able to create a measurement report at
the same time, regardless if any limits have been violated or not.
The process of turning off a limit line completely is similar to that of selecting a line.
1. Press the "Show Limit Lines"
The R&S Cable Rider ZPH hides the limit line.
2. To remove the limit lines, select the "Upper Limit" or "Lower Limit" softkey.
3. Select the "Remove" softkey.
The R&S Cable Rider ZPH removes the limit line.
7.3.4.2
Performing Limit Checks
Limit violation
Note that a limit check fails only if the signal exceeds the limit line. If the signal level is
the same as the limit value, the limit check passes.
If limit lines are active, the R&S Cable Rider ZPH automatically checks the trace for
limit violations after each frequency sweep. As long as the signal does not violate the
limit line, the R&S Cable Rider ZPH shows a "Pass" message in the measurement dia-
gram. When one single value (i.e. one pixel) is outside of the limits, the R&S Cable
Rider ZPH displays a "Fail" message in the diagram area and, in addition, sounds a
beep.
Analyzing Measurement Results
