6100-Gfast Multifunction Network Analyzer Operation Manual
124
© 2020 Radiodetection Ltd
TDR
The
TDR
(time domain reflectometer) test is a useful
tool to locate cable faults. The test is used after a fault
has been identified by running other tests, since TDR
reacts to all faults and conditions on a typical cable
pair, revealing multiple events, some of which may be
acceptable conditions.
TDR can see events as close as the ends of the test
leads. The graph controls allow you to see the
reflections and their distances so that you can find and
resolve faults; you can view the graph in either
Portrait
or
Landscape Mode
.
There are 3 modes of operation to choose from:
1.
Auto TDR
automatically searches and
determines the length of the cable, finds the
nearest significant event, and optimizes the
ranges, pulse width, and gain.
Range
and
Gain
are updated to reflect the optimized TDR
settings but can be edited.
Auto TDR
displays the distance for the
Largest Event
and updates results in
real
time
, until you stop the test. The last valid
results then remain displayed.
2.
Manual TDR
does not automate any function
nor settings and gives you full control over TDR
parameters such as
Range, Gain, VOP,
and
Pulse Width
.
The test displays results in graphical format,
updating them in real time, until you stop the
test. The last valid results then remain
displayed.
3.
xTalk
(crosstalk)
TDR
allows you to locate split
pairs between tip (A) and ring (B) copper wires
which may be causing service disruptions. The
test transmits on pair one and receives on pair
two to locate the split pairs.
To select and run a test:
1. Press the left/right navigation keys to select the
desired icon.
2. Press
to run the test.
13.1 Continuous
The
Continuous
function displays the line trace and is
continuously on and ready to use. It displays and
updates results in
real time
, in either
Portrait
or
Landscape Mode
, until you stop the test.
The last valid results then remain displayed. (Scroll
down to see examples of some common faults on the
TDR.)
Current Group
displays the test being
measured.
Current Test
allows you to select either
Auto,
Manual,
or
xTalk TDR
.
Note: If you run Auto TDR first, and use the left/right
arrow keys to change the Current Test from Auto
TDR to Manual TDR, the test will copy the TDR
parameters from the Auto TDR to the Manual
TDR, but not to xTalk TDR.