Fluke OMNIFiber, Руководство пользователя

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OMNIS
CANNER
User Guide
S-Bands™ provide a time domain limit to verify that the connections
are within the desired category of performance. In a typical link,
failures are a result of either a non-compliant connection or a faulty
cable. The ability to determine if a connection meets the expected
performance requirement significantly simplifies the diagnosis of a
failure.
Select TDRL in the DIAGNOSTICS screen and press ENTER. The TDRL
function is also available from the RETURN LOSS Graph screen.
The SELECT PAIR screen opens.
Use the (Pair) function key to select the
Pair you want to analyze.
Use or to select which end,
OMNIS
CANNER
or OMNIR
EMOTE
, 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 con-
nections as a function of distance from
the cable end. They provide a quantita-
tive 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 un-
twisted pairs at the connector.
Press ESC to exit the TDRL screen.