Motorola MC3000 Operating And Installation Manual page 19

Multiple Digital Junction Boxes can share access to a single digital radio. The digital radio
is directly connected to one master Digital Junction Box, which is connected to a second
slave Digital Junction Box. The second slave Digital Junction Box can be connected in
turn to a third slave Digital Junction Box, and so on, for a maximum of 6 Digital Junction
Boxes connected to 31 consoles and/or desksets.
The Digital Junction Box connections use RS-485 links with a maximum distance of 5000
feet between the master and the end-slave Digital Junction Boxes. Figure 2-4 shows two
Digital Junction Boxes connected in this way, where distance A+B = 5000' or less.
MC3000 Digital Deskset Operator and Installation Manual
(6880309L15-A)
Using Digital Junction Box to Connect Multiple Desksets
Installation
2-5