Ericsson RBS 2106 Hardware Reference Manual page 343

ESB
This interface is used to synchronize several transceiver groups in the same
cell, for example when one cell is built up by more than one RBS, or one cell is
split between two RBSs.
Note:
The interface is accessed on the front of the DXU through a D-sub 9-pin male
connector marked "ESB".
5.2 Operator Interface
OMT
The OMT port is used to communicate with the Operation and Maintenance
Terminal.
The OMT is connected through a 9-pin D-sub female connector.
The OMT connection is galvanically separated. All signals use RS 232 levels.
Table 3
Pin
1
2
3
4
5
6
7
8
9
Note:
Test Interface
This interface is used for test purposes only. It consists of a buffered version
of the 13 MHz signal from the OVCXO. The signal is sinusoidal shaped and is
suited for a coaxial cable load of 50 Ω.
A master-slave configuration, as in RBS 2202, is regarded as one
transceiver group.
The OMT connector pins and their functions
Function
DCD, looped from DTR (pin 4)
RXD, data out of DXU
TXD, data into DXU
DTR, looped to DCD (pin 1) and DSR (pin 6)
Signal ground
DSR, looped from DTR (pin 4)
RTS, looped to CTS (pin 8)
CTS, looped from RTS (pin 7)
RI not connected
The connector is configured as a DCE, and thus should be connected
to an IBM PC style DTE (such as a computer) with a straight cable.
9(10)
EN/LZT 720 0244 R1A