– D7 –
ND-71503(E) Rev.5.0
9papd001.fm
Echo Canceller function (NLP) Setting
The IP-PAD echo canceller circuit is equipped with a function called Non Linear Processor (NLP) and ech-
oes can be reduced by changing the setting.
[Data setting]
Set the following data to each IP-PAD.
CM0A Y=22
1st Data: 00-31: LAN Interface No.
2nd Data: 0: NLP ON
[Series 3200 R6.2 software required]
NOTE:
This function erases small sound at a level less than a certain level. Since this function erases
the background noise on the other party, some customers may feel this is strange. (At the point,
a better result can be achieved by setting NLP ON.)
PAD Adjustment
To achieve good echo erase characteristics, it is necessary to prevent the voice level in the trunk from ex-
ceeding the saturation point, even if the originator and the incoming call responder talked simultaneously.
To achieve this, enter PAD of 3dB for both transmission and reception of the 2W analog trunk line such as
COT, ODT and LDT. By this setting, the call levels of both transmission and reception drop by 3dB, how-
ever, this hardly influences the call.
[Data setting]
Set the following data to the trunk route of an analog trunk line.
CM35 Y=19
1st Data: 00-63: Trunk Route No.
2nd Data: 6: 3dB (Transit/Receive)
NOTE:
Since level dial setting becomes extremely important in digital trunks also such as ISDN trunk
and DTI trunk, make sure that the value is set to the standard value described in the manual or
adjust the value to the optimum value.
JANUARY/16/2004
COUNTERMEASURES FOR ECHO
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