DSP-100/2000

Users Manual

Split Pair

A wiring error in twisted pair cable where a wire from one cable pair is twisted with a wire from another cable pair. Though the pin-to-pin connections may be correct, splitting the cable pairs causes excessive crosstalk because the electromagnetic fields around the wires cannot cancel properly.

TDR

Time domain reflectometry. A technique used for finding cable faults and measuring cable length and characteristic impedance. A test pulse applied to the cable is reflected by impedance discontinuities along the cable (such as a short or an open). The cable’s characteristics are determined by timing the duration between the test pulse and the reflection and analyzing the shape of the reflected pulse.

TDXä

Time domain crosstalk. The TDX analyzer locates sources of NEXT along a cable. This measurement technique is patented by Fluke corporation.

Terminator

A resistor connected to the end of a coaxial cable. The terminator, which is intended to match the characteristic impedance of the cable, eliminates signal reflections by dissipating signals in the cable.

Token Ring

A local area network that is arranged in a ring or star topology and uses token passing to control access.

Twisted Pair

A cable pair made of two wires that are twisted together to minimize crosstalk to other cable pairs. The twisting minimizes crosstalk because it causes cancellation of the electromagnetic fields generated by each wire in the twisted pair.

Unshielded Twisted Pair (UTP)

Twisted pair cable that is not shielded. UTP cable is more susceptible to crosstalk than shielded twisted pair (STP) cable.

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Fluke DSP-2000, DSP-100 user manual Split Pair, TDXä, Terminator, Token Ring, Unshielded Twisted Pair UTP