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Figure 4-3(b) Trace analysis page of the OTDR
Figure 4-4 OTDR Trace
During the measurement process, the intermediate result of the measurement
is displayed on the screen. The trace is refreshed regularly to display
the entire measurement process to users. After the measurement duration
expires, the trace is the final trace, as shown in Figure 4-4.
4.2.4
Obtaining the Trace
—
Manual Measurement
If the optical fiber under test is known, you can set parameter accurately to obtain
a satisfying measurement result.
The manual measurement procedure is as follows:
1.
Change the measurement distance by selecting a preset distance range according to
3.5.3.2 "Parameter Setup."
2.
Start the measurement by pressing [Run/Stop] or tapping
on the touch screen.
The measurement process is the same as step 2 in an automatic measurement process.
4.2.5
Obtaining the Trace
—
Measurement Failure Causes
If expected events are not displayed, the failure may be caused by one of the following
reasons:
Two events are too close to each other.
Reduce the pulse width and try again. If events are still not detected, measure the
other end of the optical fiber.
The SNR is too low.
