Connecting The Omni Ta128 To Your Isdn Line; S/T Interface Model - ZyXEL Communications Omni TA128 User Manual

Chapter 2 - Installing your Omni TA128

Connecting the Omni TA128 to Your ISDN Line

The Omni TA128 comes with a choice of two types of ISDN line interfaces:
Omni TA128 comes with an S/T interface. This can only connect to your NT-1
(Network Termination) device.
Omni TA128U comes with a U interface. This allows you to connect directly to
your ISDN wall jack.

S/T Interface Model

If you have purchased the Omni TA128 or Omni TA128S/T model, you will need an
NT-1 device to connect to the network.
Although there are a lot of NT-1s on the market, most of them have two sets of RJ-11 or
RJ-45 jacks:
One set will be marked "Line," "ISDN," "Wall," or "U." It should be a single RJ-11
or RJ-45 jack.
The other set will be marked "Terminal" or "S/T." It can be either a single or
multiple RJ-45 jack(s).
Before making the connection, make sure that the termination is set up properly. The
termination set-up depends on the number of devices connected to the NT-1 and how the
devices are connected. It also depends on the distance from the device(s) to the NT-1.
Please refer to the NT-1 manual for more information.
When the telephone company installs your ISDN line, you can specify the type of jack
you want installed. You should order the jack that is recommended by the NT-1 device.
In most cases, RJ-11 jacks will be installed unless you specified otherwise (In Canada,
RJ-45 jack will be installed). The NT-1 device should come with the proper cable for
connection from the wall jack and the NT-1's line jack.
No matter what kind of wall jack you have installed, only the center two pins are
connected.
Figure 2-3
2-3