Lucent Technologies DEFINITY Administrator's Manual page 104

Troubleshooting
3. Disconnect additional telephones. The presence of other
telephones, answering machines, etc. on the line may cause
noise or extra non-linearity.
4. Check the wiring. If the module goes into retrain when a call is
received on a central office line, the wiring may need to be
modified to eliminate crosstalk. This can be a problem in-house
or at the telephone company.
5. Reposition wiring to eliminate possible interference. If the wiring
is too close to or on top of an air conditioner, a photocopier, or a
power transformer, interference may be generated on the line.
6. Check if voice compression equipment is used on the facility.
The Extender system does not work with voice compression
equipment.
7. Condition the line. Set the echo return loss (ERL) for minimum
echo. You may have to install a precision balanced network to
do this.
Issue 3 July 1997
4-13