Fluke Networks CertiFiber Pro Users Manual - Manual (Page 293)

Chapter 9: How to Use the OptiFiber Pro OTDR Module
Manual OTDR Mode
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Table 12. Manual OTDR Settings
Range
The Range is the maximum distance shown on the trace.
Select the range that is nearest to, but not less than, the
distance to the event you want to examine. If the tester
does not correctly identify the end event, select the next
higher range, then do the OTDR test again.
Auto: The tester selects a range that gives the best
possible view of the events on the fiber. The range is not
limited to the fixed ranges provided.
Pulse Width
Adjust the pulse width to a wider setting to see farther
down the fiber or to a narrower setting for better
resolution.
Narrower pulses let you see more detail in and around
reflective events and help you see events that are close
together (hidden events). But narrower pulses reduce
the range of the OTDR and make traces that have more
background noise between events. When you use
narrower pulses, small loss events can possibly be hidden
in the noise on the trace.
Wider pulses increase the backscatter level, which gives a
better signal-to-noise ratio around non-reflective events.
This helps you see smaller loss events and measure their
loss more accurately, but increases the dead zones of
events. Wider pulses can also hide small reflections.
Auto: The tester selects the narrowest pulse that still lets
you see loss events.
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