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Chronic circuit guidance, View splice results, Chronic circuit guidance view splice results – ADTRAN HDSL2 User Manual

Page 53: Figure 44, Chronic circuit problems screen

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HDSL2 for General Distribution Installation and Maintenance Practice

Control Port Operation

61223HDSL2L2-5B

43

Chronic Circuit Guidance
Selecting the Chronic Circuit Guidance option displays the Chronic Circuit Problems screen
(

Figure 44

). General information about circuits with bad splices is provided as well as a menu

to the Bad Splice Detection feature.
Splices that are varying in impedance will cause the HDSL data pump to see a reduced and/or
fluctuating signal quality (margin). The HDSL data pump will attempt to track these changes,
but when the changes become too severe, errors or loss of synchronization result. This is
reflected by the symptoms described on this screen. If a circuit meets the criteria listed on the
screen then the possibility of an impedance-varying splice should be considered.

Figure 44. Chronic Circuit Problems Screen

Descriptions of the menu items on this screen are provided as follows:

“View Splice Results”

on page 43

“Splice Histogram”

on page 44

“Reset Splice Detector”

on page 45

View Splice Results
The View Splice Results screen (

Figure 45

) reports one of three things for each transceiver in

the Splice Detection Results column:

• NTF - No Trouble is Found on the circuit.
• LOS - Loss of Synchronization exists on the circuit (remote unit has not been detected).
• Number - A number is shown if an anomaly has been detected a number of times that

exceeds the detection count threshold of eight. The number shown in this column
represents the distance, in feet, from the transceiver (Reference Point) to that anomaly.

In this example, a detection has occurred approximately 250 feet from an H2TU-C module.

Circuit ID:HNTSVLALHDSL2 03/01/05 09:29:45
Press ESC to return to previous menu
Chronic Circuit Problems

Field experience has shown that many chronic circuit failures are due to
bad splices. These type circuits generally have the following symptoms:

- Wire pairs pass all electrical tests and meet deployment guidelines.
- Large margin fluctuations will occur on the suspect pair. This can be seen
on the Detailed Status Screen. (Min & Max margins differ by > 6 dB)
- Pairs experience errored seconds (ES,SES,UAS) and/or loss of sync (LOS).
- The bad splice will most severely impair the unit closest to the splice.

This HDSL unit has the ability to test for bad splices. This detection
should be used as a last resort after all other loop testing has been
done. The detection is an approximation which can point the technician
to the general area of the suspect splice.(+/- 275 ft). For best
results, re-splice all splices close to the indicated trouble.

1. View Splice Results
2. View Histogram Screen
3. Reset Splice Detector