Fluke 990DSL, Руководство пользователя, Страница: 181 / 242

XDSL Testing and Loop Qualification
ADSL Verify Test
5
5-43
Setting Up an Impulse Noise Test
To set up an Impulse Noise test, select the test on the XDSL Toolbox and press
D
(
Setups
). Refer to Table 5-8 for setup parameters.
Table 5-8. Impulse Noise Test Setup Parameters
Parameter Setting (default in bold)
Termination Mode Terminated or Bridged
Termination Impedance 100
e
or 135
e
Measurement Filter G (ADSL), 20 MHz (ADSL2+, VDSL), 1.3 MHz,
E (ISDN BR), F (HDSLx)
Test Time Setting 15 minutes (Range = 1 to 1440 minutes)
Counter Threshold > -40 dBm (Range = 0 to -50 dBm)
Pass Threshold < 10 counts (Range = 0 to 999 counts)
Running an Impulse Noise Test
To run an Impulse Noise test, do the following:
1. From the XDSL toolbox, select
Impulse Noise
and press
L
.
2. Press
K
to start the test.
The tester begins counting noise transients that exceed the
Counter
Threshold
level in Setups.
The test automatically stops when the displayed
Elapsed Time
value
reaches the
Test Time Setting
entered in Setups. The displayed
Impulse
Count
value is highlighted in flashing, reverse-video when it exceeds the
Pass Threshold
entered in Setups.