EXFO OTDR 2 - Manual (Page 63)

Testing Fibers
OTDR 55
Defining Launch and Receive Fiber Settings
The application allows you to manually set the lengths or the events of both
your launch and receive fibers.
To set the launch and receive settings for the next acquisition:
1. From the main window, go to the OTDR tab, then tap the
button.
2. Under Launch and Receive Fiber, select if you want to apply settings
By fiber lengths or By event.