Sagem 4450E - Manual (Page 173)

SAGEM 3P@C
3P@C Installation Manual
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SAGEM SA
Analysis and troubleshooting:
Step 1 The 0km test is done on the central office distribution frame, and this
Modem can be normally synchronized. So, the Modem should be of
no problem.
Step 2 In testing the telephone, calls can be normally made. There should be
no problem to the splitter, and it is installed in the proper position.
Step 3 The environment for installing Modem indoors should excluded with
high-power devices, such as refrigerator, monitor and TV sets.
Step 4 In checking the house line, it is found that it is the parallel and aged
seriously. And after the further investigation, the house parallel is
found to be the common wires with a length of 80m or so. The line is
exposed under the sun, and the junctions of the connector are not so
firm. It is the result of unreliable house lines after analysis. The high
frequency attenuation of the parallel is great and the connection
quality is also poor, which leads the ADSL signal not to be normally
borne.
Step 5 Change the house line into the copper twisted pair of 0.4mm, and
everything becomes normal after the remaking of connectors for each
parts, and Modem can be synchronized and calls can be normally
made. This problem is solved.
Summary
The problem of house line quality is one of the common faults of external line.
Note
The synchronization of ADSL Modem should be achieved in the
respect of Modem, backbone, house line, splitter, routing method
and peripheral environment, and a correct conclusion can be
obtained with the above factors excluded.