BRX-VDSL2 User Guide
31
180-0153-001-R02
- Line error status/counts (CES, ES, SES)
- Any error messages from the DSLAM and/or the
VDSL2 test set
3. The user CPE loses synchronization
with the DSLAM when the phone
goes off-hook
You should have the following equipment to help you
troubleshoot the problem:
- Standard Telephone Test set and/or voltmeter
Verify the following measurements:
-
Voltage in ON-HOOK state on the pair from the
DSLAM and without the BRX-VDSL2 installed
should be -40VDC to -60VDC
-
Voltage in ON-HOOK state on the pair from the
DSLAM with the BRX-VDSL2 installed should be
-38VDC to -58VDC
-
Voltage in the OFF-HOOK state on the pair from
the DSLAM should be around 30VDC
-
Loop current in OFF-HOOK state on the pair
from the DSLAM should be at least 16 mA
-
Loop current in the OFF-HOOK state on the pair
toward the CPE should be at least 10 mA
If any of these measurements are not met, you
should make the corrections as per your corporate
standard procedure and re-verify.
Note:
please note that the BRX-VDSL2-X series of
VDSL2 amplifiers require the use of the Positron
BRX Power Injector to properly support concurrent
operation with a POTS service.
4. The user CPE loses synchronization
with the DSLAM when the phone
goes on-hook
When going on-hook, it may cause a small impulse
on the line, make sure you have INP enable in the
DSLAM. Recommendation: US= 1 symbol, DS= 2
symbols
B. Performance Problems: not achieving the expected bandwidth gains
5. With the BRX-VDSL2 installed on
the copper loop, the downstream
and/or upstream performance is not
meeting the expected improvement
Verify the anticipated performance using the
BRX-VDSL2 Calculator tool (makes sure to
properly specify the copper gauge)
Verify that the actual BRX-VDSL2 location
matches (more or less) the recommended
location from the BRX-VDSL2 calculator
considering the mix of various wire gauges
Verify the Min/Target/Max SNR settings and
Actual SNR values in the downstream and in the
upstream direction. A Min SNR that is too low or
a Max SNR that is too high may prevent SRA
from working properly.
Verify that SRA is enabled to allow rate adaptation to
take place and optimize the use of available
bandwidth