Fluke OMNIFiber, User Manual

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OMNIS
CANNER
User Guide
6 - 8
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 distance indicates that the connection and not the installed
cable failed.
If Return Loss fails but the TDRL graph displays peaks within the S-
Band at the connection distance, the fault is caused by the cable
portion of the link.
If failures occur at both ends of the link, use or to diag-
nose each end. Failures at both ends of the link can interact.
TDRL Examples
The following examples show the diagnostics process that is performed
to identify failures on typical links with 2 meter test cables.
GOOD CABLE, BAD CONNECTION:
The cursor in the Return Loss graph is located at
the worst Return Loss at 135.2 MHz, which is
outside the limit line. (For display purposes the
cursor was moved.) The Link failed. Why?
Press to open the TDRL screen to further
review and diagnose the graph.
The cursor is positioned at the worst peak,
which is outside the S-Bands.
Looking at the TDRL graph we can reach the
conclusion that the connection located at 2
meters did not meet the required performance
and is the cause of failure.