AT&T MERLIN LEGEND Release 2.0 Equipment And Operations Manual page 45

Introduction
Modified Key System
A Key system can be modified through system programming to provide trunk
access for special business needs. For example, some business do not require
every user to have access to a tie trunk, so the system can be programmed so
that some telephones do not have access to all outside trunks.
Figure 1-4 shows an example of personal line button assignments in a modified
Key system with two outside trunks and one tie trunk. Each trunk is not
assigned to a button on every telephone.
Figure 1-4. Lines Labeled for Modified Key System Telephones
Hybrid Key System
A hybrid Key system allows ground-start trunks to be connected directly to the
system's control unit. To program ground-start trunks in Key mode, the system
may not be strapped for Key-only operation and must be registered with the
FCC under an MF classification, as described later in this chapter, in the section
FCC Registration. In this configuration, all outside trunks, including ground-start
trunks, are assigned to personal line buttons on each telephone.
Key Mode Considerations
The multibutton telephones most commonly used in a Key system
provide easy access to outside trunks. To get a dial tone, the user
simply lifts the handset and an outside line is automatically selected.
The intercom path helps ensure that outside trunks are available when
needed.
Modes of Operation 1-17