If the local telephone company has provided an RJ21-type network interface, you cannot connect your control unit to the network interface directly with modular line cords. You must first extend the network interface to a group of single-pair modular jacks mounted in a jack panel box in the jack field. Then connect the control unit to your outside lines by plugging the modular line cords into the jacks.
You need the following equipment (Figure 41) to extend an RJ21 network interface to the jack field:
●4-line adapter
This should be a cutdown-to-modjacks adapter that provides four single- pair jacks for the MERLIN Plus system control unit. One adapter accommodates four outside lines.
●Jack panel box (apparatus box)
The box should hold two 4-line adapters, and be identical to the jack panel boxes with the voice terminal wiring labels in the jack field.
●Single-ended 25-pair connector cable
This cable has to be long enough to reach from the network interface to the jack field with some slack. Before you order this cable, check to see whether the 50-pin connector at the network interface is male or female and order a length of cable with a 50-pin connector of the opposite gender.
●Labels
FIGURE 41 Equipment for extending the network interface to the jack field.
