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cable is tried on the LAN, it does not
work .This is because the lack of the proper
pairing causes excessive cross talk in the
cable, preventing the LAN from working. This
type of cable fault is sometimes call a split
pair or double split pair to detect this type of
fault, a more sophisticated tester capable of
performing a NEXT test(Near End Cross Talk)
must be used. Both the Pair Master and LAN
TDR can perform NEXT tests.
Notes:
Cross talk increases with the length of the
cable. A LAN system will tolerate a certain
amount of cross talk. A short cable (10ft or
less) that is improperly paired may work just
fine. However, longer cables paired in exactly
the same way, may not work. This explains
why an installer can make short jumper
cables that work (although they are
improperly paired), but when he installs
RJ-45’s in exactly the same way on a longer
cable, the cable does not work.
6.3.
The
CABLE SNIFFER-REMOTE
says
my phone cable is bad, but my phone
works ok.
Most single line telephones only use 2 wires
in a modular cable the modular cable, which
terminates in RJ-11 connectors could have as
may as 6 wires in it. The unused wires may
have faults, which the 4 in 1 identifies, but
these faults may have no effect on the
working 2-wrie telephone circuit. Many
