EXFO VDSL2 - Manual (Page 95)

VF Tests
Copper, VDSL2, ADSL2+, and IP Triple-Play Test Set 87
Longitudinal Balance
Longitudinal Balance
The Long. Balance test allows you to
check that the VF longitudinal balance
ratio for the twisted pair complies with
applicable standards so as to reduce
the effects of common-mode voltage
to ground. The better the longitudinal
balance of the cable pair, the higher
the dB reading.
To start/stop the test:
Press
to start/stop the test.
Test results are displayed on the screen as they are completed.
Load Coil Detection
The Load Coil detection test allows
you to detect the presence of load
coils, which are detrimental to the use
of DSL technologies on the line. If a
load coil is detected, use the time
domain reflectometry (TDR) test to
quickly locate and remove it from the
cable.Test results are displayed in
graphical form.
To move the screen pointer:
Press the left/right arrow key to move the screen pointer. The pointer value
updates dynamically.