EXFO OTDR 2 - Manual (Page 57)

Testing Fibers
OTDR 49
9. Select the desired distance range, pulse, and time values. For more
information, see Setting Distance Range, Pulse Width, and Acquisition
Time on page 60.
Note: To configure different parameters for each wavelength, see Applying
Acquisition Settings by Wavelength on page 59.
10. Tap Start. If the first connector check feature is enabled, a message
will appear if there is a problem with the injection level (see Enabling
or Disabling the First Connector Check on page 57).
Note: The acquisition starts with the selected wavelength. The following
wavelengths are tested in increasing order (smallest to largest).
You can modify the acquisition parameters as needed while the acquisition
is in progress. The OTDR simply restarts the averaging each time a
modification is made. This applies only to the wavelength currently under
test. Changing the time parameter does not restart the acquisition.