EXFO OTDR 2 - Manual (Page 69)

Testing Fibers
OTDR 61
Setting Distance Range, Pulse Width, and Acquisition Time
You can use the same distance range, pulse width and acquisition time
parameters for testing at all wavelengths on a multiwavelength OTDR. For
more information, see Applying Acquisition Settings by Wavelength on
page 59.
To set the parameters:
From the OTDR tab:

Tap the dial corresponding to the parameter you wish to set (the
selection marker will move clockwise).
OR

Tap directly the value to select it. The selection marker will go to that
value immediately.
Note: If your OTDR supports singlemode, singlemode live, or multimode
wavelengths, settings would be applied to either singlemode, singlemode
live, or multimode wavelengths, depending on the selected fiber type
(same settings for 50 m and 62.5 m).
I
MPORTANT
To test the high-resolution feature, you must set a minimum
acquisition time of 15 seconds.
Parameter-setting dials
Selection
marker