User guide

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OMNIScanner User Guide
The SELECT PAIR screen opens.
Use the (Pair) function key to select the Pair
you want to analyze.
Use or to select which end, OMNI-
Scanner or OMNI Remote, you want to view the
results for.
Press to open the TDRL screen
The screen displays the TDRL (Time Domain Return Loss) graph. The
funnel-like lines are the upper and lower S-Bands. S-Bands are limit lines
for connections as a function of distance from the cable end. They provide
a quantitative measure of Return Loss at the connection point, which is
typically located at the end of the test cable, at about 2 meters (7ft). The
measurement unit for the horizontal graph can be displayed in meters (m)
or feet (ft.).
Initially, the cursor is located at the point with the worst Return Loss.
The Return Loss at the cursor position, the corresponding pair, and the
distance to the cursor position are displayed above the graph.
The example shows a Time Domain Return Loss that exceeds the S-
Bands. The worst Return Loss is displayed at 7ft, the connection. The
conclusion is that the reflection at the connection is the cause of the failure.
This could be due to a connector problem or excessively untwisted pairs at
the connector.
Press ESC to exit the TDRL screen.
Using TDRL to Diagnose a Link
S-Bands provide an easy method to
pinpoint if the fault is located at the
connection or at the cable. The S-Bands
allow you to determine if the connections
in a link meet the desired performance
level. They are designed to match the
standard category of the selected
Autotest.
A graph containing peaks that are located
outside the S-Band at the connection