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8. Fiber Optic Reference
8.1 Establishing the Reference
Different methods can be used when making a reference measurement with
OMNIFiber. The reference measurement to use depends on how the standard
defines the link, and how the end equipment is interconnected. There are three
basic link definitions and three corresponding reference methods.
Link Reference Multimode Single-mode Where
Definition Method Standard Standard Used
link=2 cross 1 jumper method TIA-526-14A TIA-526-7 TIA-568A,
connects + or equivalent Method B Method A ISO 11801
cable plant 100BASE-X,
ATM, Fibre
Channel,
FDDI,
Token Ring
link=1 cross 2 jumper method TIA-526-14A TIA-526-7 10BASE-X,
connect + or equivalent Method A Method A.2 TIA 455-171
cable plant Method B
link=cable 3 jumper method TIA-526-14A TIA-526-7
plant or equivalent Method C Method A.3
8.2 The Launch/Jumper Cable
The launch/jumper cables are 2 m fiber cables and need to be of good quality and
in excellent condition. Always clean the launch cable before use.
NOTE
The launch cable used to set the reference value should be the same
type of fiber as the cables to be tested and certified, 50/125, 62.5/125 or
singlemode.
CHAPTER 8: OMNIFiber Reference