Specifications

Cable, CompactFlash and Accessory Specifications
A-14
Balun for E1 or PRI NIM Cards
Some overseas electrical systems require that you use a balun and grounding shunt when utilizing
an E1 or PRI NIM card on the XSR. A balun is an adapter employed to connect a 75-ohm coaxial
cable pair (2 BNC connectors) to a 120-ohm twisted pair cable (RJ-48C connector).
The balun and its connectors are illustrated in Figure A-14. The grounding shunt is also required
to ground unused pins of the RJ-48C connector.
To install the balun, attach the 75-ohm coaxial cables to the BNC connectors and a 120-ohm E1/
PRI cable to the RJ-48C port (see below for details).
Figure A-14 Balun for E1 or PRI Connection
RX In TX Out
G.703 Balun
Model 460 MC
N
IM
-E1-C
O
AX-BLN
J12 Transmit BNC
male connector
75-ohm connection
to your network
120-ohm
connection to XSR
J2 Receive BNC
male connector
75-ohm connection
to your network