Specifications

72 AR Router
C613-03058-00 REV A
Primary Rate ISDN Interfaces
Primary Rate ISDN interfaces on the AT-AR390 and AT-AR395 support
connection to either 75Ω or 120Ω networks. The 75Ω interfaces conform to the
standard BNC method of connection to 75Ω coaxial cable (Table 31 on page 72).
Since there is currently no official international standard for “pluggable”
connection to a 120Ω system, 120Ω interfaces employ the RJ-45 method of
connection used by most other manufacturers (Table 32 on page 72).
Primary Rate ISDN interfaces on the AT-AR020 PRI E1/T1 PIC and AT-AR025
PRI/G.703 PIC support connection to 120Ω networks using the RJ-45 method
of connection used by most other manufacturers (Table 32 on page 72). An
external balun is required to connect to a 75Ω network.
Voice Ports
Voice ports on the AT-AR300(S) and AT-AR310(S) use a standard RJ11
telephone socket that provides a Tip and Ring A/B pair (Tabl e33 on page 72).
An RJ11-to-BT adaptor cable can be used to connect telephones with BT-style
plugs to RJ11 ports (Figure 52 on page 89).
Table 31: Connection standard for Primary Rate ISDN BNC 75Ω connectors.
Signal Connection
TX-/RX- Outer conductor (i.e., shield)
TX+/RX+ Inner conductor
Table 32: Connection standard for Primary Rate ISDN RJ-45 120Ω connectors (from
left to right, with latch down, as viewed from the rear) .
Pin Signal
1RX+
2RX-
3 RX ground selection from jumper
4TX+
5TX-
6 TX ground selection from jumper
7 Not connected
8 Not connected
Table 33: Pinout of the voice port RJ11 connectors .
Pin Function
1 Not connected
2 Not connected
3RING
4TIP
5 SHUNT
6 Not connected