3. Operating Instructions
Figure 3.13.
A horizontally zoomed-in view of the cable fault with active (solid) cursor
at the start of the fault (“toe” region) and inactive (dashed) cursor at the peak of the
fault. The DTF measurement is highlighted (red circle).
Figure 3.14.
Relative distance measurement between two small impedance “faults”
caused by BNC connectors.
place the cursors on the “toe” region of the faults where the TDR trace is just beginning to rise
above or fall below the cable characteristic impedance.
3.11.3. Multi-Segment Cable DTF Measurements
Cable assemblies are sometimes made up from different types of cables in series, each of which
may be chosen for unique characteristics such as high-temperature operation or radiation
resistance. Such cables frequently have different velocities of propagation (Vp), making
Distance-to-Fault (DTF) measurements difficult. If the average Vp of the assembly or the Vp of
any one cable assembly is used, it will result in inaccurate distance measurements along the
length of the compound cable.
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CT100B TDR Cable Analyzers Operator’s Manual
