EXFO CableSHARK P3 VF/DSL Cable Qualifier - Manual (Page 65)

CableSHARK P3 User Guide
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Section 7 Quick Start Guide to CableSHARK Tests
7.1 Introduction
xDSL implementation can be affected by signal attenuation, signal cancellation due to reflections caused by
bridge taps, crosstalk noise, impulse noise and random electrical noise from the environment. To qualify a
circuit for an xDSL application, or when a circuit has a problem with the cable impairments, CableSHARK
allows the user to perform various tests for the cable qualification or troubleshooting purposes.
For all tests, if the termination impedance is unknown, it can be left as default since the CableSHARK will
find the best impedance matching automatically for each test.
The Noise Filter parameter for some tests can be set to different filters. For normal cases, it should be set to
NO FILTER to measure the characteristics of the cable. For some applications and cases where the effect
of adding a noise filter is required, the technician can set the noise filter to the appropriate one. A summary
of the noise filter setting for DMT, PSD Noise, and Spectral Detective Tests are as follows:
NO FILTER or G FILTER for ADSL Application
NO FILTER or F FILTER for HDSL Application
NO FILTER or E FILTER for ISDN Application
The following subsections feature an easy to understand description on running the various tests with the
CableSHARK.
7.2 TDR Tests
The TDR test is used to identify and locate all types of faults as well as bridge taps (multiple appearances)
and load coils. For optimal results, perform a TDR from either end of the cable to precisely locate any faults
and overcome any concerns caused by cable type, cable size, or impairments on the line.
7.2.1 Automatic TDR Test
Note: this is a Single-Ended test.
1. From the Main Menu, select CABLE TESTS (function button F1)
2. Choose TDR from the pop-up menu, and AUTO – CABLE END from the sub-menu. Press the
RUN/STOP key.
3. Set any other parameters as required for the particular situation (Cable Type, VOP, and Horizontal
Units).