Press Limits (F4) to display and change Attenuation limits at various frequencies.

Press Save (F1) to store the new values.

Press the ESCAPE key to return to the Attenuation screen.

Note: See Customizing Attenuation Limits in Chapter 3 for more information on Attenuation limits.

Length/Delay

To display the LENGTH/DELAY screen, press the Measure Cable Performance key, then select Length/Delay.

The pairs are shown on the left and the length for each pair is shown in the second column. The third column shows the propagation delay values in nanoseconds (nS) and the fourth column indicates the condition of the wire pair (open or short). The Skew value is the worst-case value of the difference in propagation delay between the wire pairs.

Press the ESCAPE key to return to the MEASURE CABLE PERFORMANCE screen.

Impedance

To display the IMPEDANCE screen, press the Measure Cable Performance key, then select Impedance.

The pairs are shown on the left and the impedance values in ohms (Ω) are shown on the right.

Press the ESCAPE key to return to the Measure Cable Performance screen.

Loop Resistance

To display the LOOP RESISTANCE screen, press the Measure Cable Performance key, then select Loop Resistance.

The pairs are shown on the left and the loop resistance values in ohms (Ω) are shown on the right. Press the ESCAPE key to return to the MEASURE CABLE PERFORMANCE screen.

Capacitance

To display the CAPACITANCE screen, press the Measure Cable Performance key, then select Capacitance.

The pairs are shown on the left and the capacitance values in picofarads (pF) are shown on the right.

Press the ESCAPE key to return to the Measure Cable Performance screen.

Noise

Noise is undesirable electrical activity that interferes with a network’s ability to transmit data reliably. Noise sources in networks may include AC transmission lines, fluorescent light fixtures, industrial equipment, elevators, etc. Noise problems also occur when other wire pairs in the same sheath are used for non-LAN applications.

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Microtest TSB-67 - 568A Annex E manual Length/Delay, Noise