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EXFO CableSHARK P3 VF/DSL Cable Qualifier User Manual

Page 122

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VF / DSL Cable Qualifier

110

EDIT /
SELECT

MAIN
MENU

Test Type :
Term Impedance :

Termination:
Noise Filter :
Imp Nse Threshold:

Plot Interval:
Meas Time (Hour):

Measurement Units:


100 OHMS

TERMINATED
NO FILTER
43

dBm
1 Minute
1

E

F

CHG

IMPULSE HISTOGRAM

WARNING

Note: telephone cables may have dangerous A.C. or D.C.
voltages on them, therefore caution should be taken when

connecting this test set.

!

SELECT
NEXT



-

F

IGURE

8.4.1D

I

MPULSE

H

ISTOGRAM

T

EST

S

ETUP

M

ENU

The NOISE TEST SETUP Menu has several options that appear at the upper part of the screen (see the
previous illustration). The parameters can be modified to customize a noise test. The noise test setup
options are described as follows:

TEST TYPE:

Select from NOISE PSD Next/Fext 2.2 MHz, NOISE PSD Next/Fext 6.0MHz,
IMPULSE NOISE and IMPULSE HISTOGRAM.

The PSD NOISE test measures the PSD noise energy and displays the result in
terms of dBm/Hz. For this test, no test signal is impressed onto the line under
test. The background cable signal is converted to a RMS voltage reading.

For Impulse Noise, no test signal is impressed onto the line under test. The
background cable signal is analyzed for a predetermined time to count the
number of noise spikes higher than the user selected threshold.

For Impulse Histogram, the CableSHARK plots impulse noise spikes over a user
definable time period.


TERM IMP:

The CableSHARK's impedance needs to match the characteristic impedance of
the cable. This causes the CableSHARK at either end of a test (including Single