3. Operating Instructions
Use this correction to make more accurate impedance measurements on a length of cable. Since
uniform cables tend to have a characteristic resistive loss per unit length or “dribble up”, one
technique is to adjust the correction until the cable is as flat as possible. Another technique is to
attach a known impedance reference, such as a resistive terminator, to the cable and adjust the
ohms per unit length correction until the measured impedance reads the correct value.
Figure 3.31.
Resistive cable loss correction, before. Note that the trace slowly rises.
Figure 3.32.
Resistive cable loss correction, after. Note that the trace is nearly
horizontal.
3.11.17. Return Loss (S
11
) Traces
This feature uses precision open, short, and 50 ohm load (OSL) calibration standard
measurements to correct for systematic errors in the pulsing and sampling electronics, producing
a more accurate S
11
result on the Device Under Test (DUT). The procedure for creating an S
11
return loss plot is as follows:
CT100B TDR Cable Analyzers Operator’s Manual
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