Launch level – EXFO FTB-7000 OTDR for FTB-200 v2 User Manual
Page 318
Advertising
Description of Event Types
304
FTB-7000 Series
Launch Level
Launch Level
This event indicates the level of the signal launched into the fiber.
³
The figure above shows how the launch level is measured.
A straight line is plotted using least-square approximation to fit all trace
points in the linear area between the first and second detected events.
The straight line is projected toward the Y-axis (dB) until it crosses the
axis.
The crossing point indicates the launch level.
³
<<<< in the events table indicates that the launch level is too low.
Reflected power
(dB)
Distance
(km)
Launch level
event position
Second event
Launch
level
Linear area
Advertising