User guide

OMNIScanner User Guide
6 - 6
NEXT in the cable is the source of the failure
even though the cable’s NEXT response peaks
are less than those of the connection. By
knowing that the connection meets its perfor-
mance requirement, the cable is easily identi-
fied as the non-compliant component of the
link.
The following table summarizes the typical
diagnosis process.
NEXT TDNXT exceeds Conclusion
S-Band limits
PASS N/A NEXT of link is within limits
FAIL YES Connection fails. Replace or reterminate.
Plug and/or jack can be at fault.
FAIL NO Cable is not within specifications
TDRL
Return Loss is a measure of the amount of reflected energy in a link.
Reflections occur at points of impedance discontinuity, such as connectors,
transitions from patch cables to horizontal cables, and impedance structure
within a cable.
Return Loss faults are diagnosed by using the TDRL (Time Domain Return
Loss) function. OMNI Scanner uses TDRL to determine the amount of
Return Loss as a function of distance. TDRL with new S-Band™ technol-
ogy (Standard Connector Band technology) can help you to distinguish
between connection faults and cable faults. It assists you with diagnosis
and troubleshooting of Return Loss failures and the verification of test
cables, connectors and plugs.
While the Return Loss graph shows the link test limits and the frequency at
which a failure occurred, the TDRL graph displays Return Loss vs. dis-
tance.