OptoTest OP940-SW, Инструкция по эксплуатации

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OP940-SW
Input
Inpu
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If the reference cable is APC-terminated, use a short APC-to-PC cable to reference RL.
Alternatively, utilize the APC Reference option.
Once this option is selected, simply press the
Start RL Ref button.
With the APC Reference option selected, the OP940 will scan for reflections much
smaller than it would normally consider to be relevant for RL referencing purposes. As
a result of the criteria being much broader, the unit is more likely to pick up unintended
reflections. To ensure that the unit references to the proper distance, minimize all
reflections between the front panel of the unit and the intended reference location.
Additionally, it is possible that the reflection from some APC cables is small enough that
the unit will have a hard time detecting it. In this case, it is suggested to place a dust cap
on the end of the fiber to increase the light reflected back at that location, or one can
place the open end into the OPM, which will increase the light reflected as well.
If the APC Reference option still does not allow the unit to reference to the APC
connector, it is suggested that a short (three-to-six inch) APC-to-PC cable be utilized to
create the large reflection.
Note: If the unit is referencing to a UPC connector, the APC Reference option should
not be utilized.
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Example 2: Referencing Return Loss with APC Reference Cables