Page 60 of 130
Figure 66: MDU 25
Tii ISB
The Tii Intercom System Bypass (ISB) module, or ISB, is a solution for interrupt style Enterphone systems,
where the customer premises is serviced by a single riser pair, and they subscribe to services such as TELUS
TV or xDSL.
The mounting plate, which holds up to 12 modules, is mounted with the entrance protectors and should be
mounted as close to the incoming CO, house and Enterphone cables as possible, where enough plywood
space is available to accommodate a foot print of 8” (20 cm) wide x 13” (33 cm).
The Tii ISB uses insulation displacement connectors.
When using an ISB, the POTS splitter is placed in the suite. The
connections are:
1. Input line – Jumper to the CO Cable
2. Line output – Jumper to riser pair
3. To enter system – Jumper to intercom system input
4. From Enter system – Jumper from intercom system output
1.9.1 Jack Terminations – OLD and NEW
RJ11 Jack
We’re going to take a look at some jack terminations now, both old and new. You need to be familiar with
the old style jacks as well since you will encounter them in the field.
At one time, RJ11 jacks like the one shown here, were the standard telephone jacks used with all residential
telephones. This is the inside wiring of the jack.
