User guide

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OMNIScanner User Guide
Press (Graph) to display the Attenuation
graph for the highlighted pair. The Attenuation is
displayed for the frequency indicated by the cursor
position.
Press (Pairs) to view Attenuation results for
other pairs.
Press ESC to exit the ATTENUATION screen.
Return Loss
The Return Loss function measures the uniformity of a cable’s imped-
ance. OMNI Scanner injects a signal into the cable and measures the
reflected signal strength. Return Loss measures the difference between the
transmitted signal delivered to the cable and the reflected signal at the
input port of the cable. The reflected signal is the result of impedance
mismatches in the link under test.
In the RETURN LOSS screen, the worst case
margin for all pairs is shown at the top of the screen.
The pairs are displayed in the column on the left
side, followed by the Return Loss in decibels (dB),
the Return Loss Limit, and the frequency. The result
for each pair is tagged with a PASS or FAIL
indicator.
Press or to toggle between the Return Loss results for
OMNI Scanner and OMNI Remote .
Press (Graph) to display the Return Loss
graph for the highlighted pair. The Return Loss is
displayed for the frequency indicated by the cursor
position.
Press (Pairs) to view Return Loss graphs for
other pairs.
Press (Diagnostics) to display the TDRL screen, where cabling and/
or connection faults can be identified. (See Chapter 5 - Diagnostics: Using