On-site Maintenance Manual
Airbridge cBTS3612 CDMA Base Station
Chapter 6 Switches &
Interfaces
6-2
Table 6-1
BCIM DIP switch and jumper settings
Item No.
Function
Operation
S2~S9
Impedance (75Ù/120Ù) for
E1 interface, balanced
mode or unbalanced mode
selection.
The No.1-4 of the DIP switch are all set
at “off” position: 120Ù twisted pair line.
The No.1-4 of the DIP switch are all set
at “on” position: 75Ù coaxial cable, with
the coating connected to the PGND.
The No.1-2 of the DIP switch are all set
at “on” position, No.3-4 at “o ff” position:
75Ù coaxial cable, the coating is not
connected to the PGND.
The DIP switch position other than the
above mentioned is not defined.
J6
Feedback of the
Impedance mode
(75Ù/120Ù) for E1
interface, the program will
initiate the E1 chip
according to this jumper
status.
Short-circuiting the No. 2 and No.3:
120Ù configuration mode.
Short-circuiting the others or leaving
them unconnected: 75Ù configuration
mode.