Introduction
1-5
3170-A2-GB20-20
December 1996
Table 1-1
Rear Panel Connectors and Switches
Name
Function
POWER
Supplies power to the E1 DSU/CSU by providing an attachment for the ac power
module or the optional dc power cable (+24 or –48 Vdc).
AUX PORT
Supports SNMP LAN Adapter or daisy-chain connections.
COM PORT
Provides access to a locally connected PC, an ASCII terminal or printer, or an
SNMP management link.
DTE
Provides access to the DTE Drop/Insert interface. This interface is compatible
with the signal format of CCITT Recommendation G.703 and the frame structure
of CCITT Recommendation G.704.
NETWORK—120
Ω
Provides an unkeyed modular jack for a 120 ohm balanced network interface.
NETWORK—75
Ω
TX/RX
Provides two BNC connectors (Transmit and Receive) for a 75 ohm unbalanced
network interface.
NETWORK—120
Ω
/75
Ω
(switch)
Selects either a 120 ohm balanced network interface or a 75 ohm unbalanced
network interface.
NETWORK—RX SHIELD (switch)
Selects either an “open” or “earth” shield connection for the 75 ohm RX interface.
(This switch must be set to “open” when using the 120 ohm interface.)
CLOCK IN
Used to attach an external clock to the E1 DSU/CSU.
PORTs 1– 4
Used to connect the customer’s synchronous data DTE to the E1 DSU/CSU.
