EXFO FTB-7000 OTDR Series for FTB-500 - Manual (Page 86)

Testing Fibers in Advanced Mode
72 OTDR
Setting Distance Range, Pulse Width, and Acquisition Time
³
Time: corresponds to the acquisition duration (period during which
results will be averaged). Generally, longer acquisition times generate
cleaner traces (this is especially true with long-distance traces)
because as the acquisition time increases, more of the noise is
averaged out. This averaging increases the signal-to-noise ratio (SNR)
and the OTDR’s ability to detect small events.
You can select either Auto or one of the displayed values.
If the predefined values do not suit your needs, you can customize one
or all of them. For more information, see Customizing the Acquisition
Time Values on page 120.
If you select Auto, the application will use the autorange acquisition
time that you have previously defined (see Setting the Autorange
Acquisition Time on page 68). It will also evaluate the fiber type and
length, and set the acquisition parameters accordingly.
You can use the same distance range, pulse width and acquisition time
parameters for testing at all wavelengths on a multiwavelength OTDR.
I
MPORTANT
To test using the high-resolution feature, the acquisition time must
be of at least 15 seconds.