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Introduction and Description
If your ISDN product operates with a S/T outlet interface, you need an NT1 device to connect to the ISDN switch. MTA128ST adapters need an NT1 device to connect to the ISDN switch, but the MTA128NT adapter does not require NT1 device. In the UK, and in many European countries, NT1 device is supplied by your telephone company.
Figure 2-1 ISDN Interface Points
S/T Interlace
The S/T interface uses an
Table
Pin | TE Signal |
1Not used
2Not used
3Tx+
4Rx-
5Rx+
6Tx-
7Not used
8Not used
U Interlace
The U interface uses a
In Table
Pin
1N/A
2N/A
3N/A
4Positive Input
5Negative Input
6N/A
7N/A
8N/A
6