EXFO FTB-700 for FTB-1 - Manual (Page 147)

Analyzing Traces and Events
OTDR 139
Inserting Events
Four markers are available to measure the inserted event, but only
marker A identifies where the event will be inserted. Use the marker
arrows to move marker A on the trace display.
3. Once you have determined the location, under Event, use the
up/down arrows next to the box to select the desired event type.
4. Press OK to insert the event or Cancel to return to the events table
without making any changes.
Inserted events are marked with asterisks (appearing beside the event
number).