U-Interface pinouts are a simple straight-through cable:
Pin 1
Pin 2
Pin 3
Pin 4	Tip
Pin 5	Ring
Pin 6
Pin 7
Pin 8

Note that this is fundamentally the same as for POTS. You can even get away
with using a standard wall cord between the NT1 and a RJ-11 or RJ-45 wall
jack, though the specifications are much more stringent.
o

The S/T interface cable is as follows:

From NT1	To TE
1
2
3	Transmit+	Receive+
4	Receive+	Transmit+
5	Receive-	Transmit-
6	Transmit-	Receive-
7
8