Operation Manual

DTX Series CableAnalyzer
Technical Reference Handbook
7-12
Types of Compensation
The tester offers three types of compensation:
• Launch Only: Lets you compensate for a launch fiber.
• Launch + Receive: Lets you compensate for a launch
fiber and a receive fiber.
• Launch + Fiber + Receive: Lets you compensate for a
launch and receive fiber if you have forgotten to do so
before the receive fiber was taken to the other end of
the cabling.
Notes
Launch + Receive compensation usually provides
the most accurate measurements.
Avoid using Launch + Fiber + Receive
compensation on fibers longer than 8 km. Doing
so may degrade measurement accuracy.
Setting the Launch Fiber Compensation
1 Turn the rotary switch to SETUP, select Fiber OTDR; then
select the OTDR Port to be used (multimode or
singlemode).
2 Turn the rotary switch to SPECIAL FUNCTIONS; then
select Set Launch Fiber Compensation.
3 On the Set Launch Method screen highlight the type of
compensation you want to do.
4 Clean the tester's OTDR port and launch fiber
connectors.
5 Connect the fibers to the tester's OTDR port as shown
on the screen and in Figures 7-5, 7-6, or 7-7; then press
P.
The tester attempts to identify the launch and receive
fiber ends based on the launch method you selected,
and displays the results in the Event Table (Figure 7-8).
In the Event Table, the launch event is shown as
V, the
receive event is shown as
X and the launch/receive
event is shown as
W.
You can manually select the launch and receive events if
necessary by highlighting events and using the softkeys.
See page 7-17 for details.
6 To see where the markers are set on the trace, press
J View Trace.
7 Press N; then press K OK. Launch Compensation is
automatically enabled in Setup.
Figure 7-9 shows an example of an OTDR trace with launch
and receive markers enabled.