EXFO CableSHARK P3, User Manual, Page: 70 / 321

VF / DSL Cable Qualifier
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The Rx unit will calibrate itself first and then try to synchronize with Tx unit. Once both units are
synchronized, the test will be carried out. The whole process is automatic. When a test is completed, the
CableSHARK’s large graphical display will show the results of the DMT test. The user can then move the
cursor to get all the information presented both graphically and numerically. The Rx unit can initiate another
End-To-End test again and again since the Tx unit is set to Remote Responder mode. To repeat the test,
press the RUN/STOP button. You can also change option settings if you wish by pressing the function button
associated with TEST SETUP.
7.5 Noise Tests
Note: This is a Single-Ended test.
The CableSHARK noise test performs Noise PSD (Power Spectral Density), Impulse Noise and Impulse
Histogram Measurements.
1. From the Main Menu, select CABLE TESTS (function button F1).
2. Choose NOISE from the pop-up menu.
3. Select Noise PSD Next/Fext or the Impulse Noise Test or the Impulse Histogram Test and set the other
parameters if required. Parameters for the Impulse Noise test include Impulse Noise Threshold and
Impulse Noise Measurement Time which allows the user to configure the Impulse Noise test to meet
their requirements, for the Impulse Histogram, parameters include Impulse Noise Threshold, Plot
Interval and Impulse Noise Measurement Time.
4. Press the RUN / STOP button to start the test. The results will be displayed on screen in an easy to
understand format.
To repeat the test, press the RUN/STOP button.
7.6 Longitudinal Balance Test
Note: This is a Single-Ended test.
Longitudinal balance ratio is defined in ITU-T Rec. O.9, which is important when it comes to reducing the
effects of common-mode voltage to ground. The CableSHARK can perform a longitudinal balance
measurement to determine if the longitudinal balance ratios are compliant with a standard. The
CableSHARK displays results for ADSL applications respective of the ANSI T1.413 standard. The test
results can also be used for ISDN and HDSL applications. The better the balance of the cable pair under
test, the higher the dB reading resulting from the measurement.