Microtest TSB-67 - 568A Annex E Manuel D’Utilisation

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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.