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Chapter 13 Copper Testing
OneExpert DSL User's Guide
22052280, Rev. 015 April 2019 208
Wideband balance sweep testing
This feature regulates how well a copper pair rejects noise.
1. Connect the Tip and Ring (A and B) leads of the ONX to the line under test.
2. Connect the ground (E) lead of the ONX to ground.
3. Select
Mode , and then select Balance Sweep .
4. Choose the Number of Averages . If averaging is enabled, you will see the trace
completely painted. Afterwards, it will update to reflect the average.
5. Press the Start softkey.
6. The graph will start populating.
The test is complete.
Near-End Crosstalk (NEXT) sweep testing
This test detects coupling from one pair of wires to another at the near end over a range
of tone frequencies. The ONX transmits a range of frequencies on T1/R1 (A1/B1) and the
crosstalk is measured on T/R (A/B). This allows coupling from one pair to another to be
detected. You can specify the range of the sweep by selecting VDSL (25 kHz to 35 MHz) or
ADSL2+ (10 kHz to 2.2 MHz) from the Technology menu.
An UltraFED IIB may be used to terminate the far end of the line by selecting Terminate
with UFED from the Options menu.
1. Connect both Tip (A) and Ring (B) pairs (T/R and T1/R1 or A/B and A1/B1) to the lines
under test.
2. Select NEXT Sweep from the Mode menu and press the Start button.
3. The ONX begins the test. A graph appears in the NEXT Sweep screen.
The current frequency and NEXT measurement appear at the top of the graph cursor.
The graph cursor is a vertical line that shows the position of the current frequency.
4. You can view NEXT results for different frequencies by moving the cursor. Use the
left and right arrow keys or press and drag the cursor to move the cursor to different
frequencies.
You have completed the test.