JDS Uniphase SmartClass VDSL, Руководство пользователя

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Chapter 7 Troubleshooting
Resolving problems
SmartClass VDSL Tester User’s Guide 29
General testing
The following section addresses questions about testing in general using
SmartClass Testers.
Issue
Inconsistent test results.
Resolution
Verify that your test leads are good and are connected properly for the test you
are performing.
VDSL testing
The following section addresses questions about VDSL testing.
Issue
The modem cannot achieve synchronization with the Central Office (CO).
Resolution
Inability to sync can have many causes. Perform the following steps to trouble-
shoot:
Disconnect the customer's VDSL modem.
Verify you are connected to the correct pair.
Isolate the premise wiring.
Check for a premise alarm system.
Verify that the copper pair is provisioned for VDSL at the CO.
Try testing at the CO/Exchange on the customer pair.
Check the DSLAM modem vendor and software version.
Issue
The modem gets sync with the CO, but the rate is lower than expected.
Resolution
Verify that you are on a VDSL line.
Check whether the max rate on the DSLAM is limited.
Check for a premise alarm system on the same pair.
Check the attenuation.
Make sure that you are connected on pins 3 and 4 instead of 2 and 5.
Verify the noise margin.