3 Board
M900/M1800 BTS3X Series Base Transceiver Station
Hardware Description Manual
3-74
Huawei Technologies Proprietary
Issue 01 (2006-11-18)
!
The states of bit 1 and bit 2 must be consistent, so do bit 3 and bit 4.
!
S1, S2 only control the resistance of the Rx E1, independent with the resistance of Tx E1.
!
S9 only controls the impedence of the Tx E1 and is independent of the impedence of Rx
E1.
Figure 3-49
TMU DIP switches
DIP
Switch
DIP Bit
Meaning
Default
Setting
S1
4
ON: E1 port resistance is 75-ohm; OFF: E1 port
resistance is 120-ohm.
Bit 1 and 2 control the resistance of the fourth E1;
Bit 3 and 4 controls the resistance of the third E1.
All ON
S2
4
ON: E1 port resistance is 75-ohm; OFF: E1 port
resistance is 120-ohm.
Bit 1 and 2 control the resistance of the second E1;
Bit 3 and 4 controls the resistance of the first E1.
All ON
S9
4
Bit 1 controls the first four E1 resistance settings.
ON: The first to the forth
E1 port resistance are 75-
ohm;
OFF: The first to the forth
E1 port resistance are 120-
ohm.
Bit 2, 3, and 4 are used to indicate the timeslot number
of the local OML in the case that BTS supports Abis
bypassing. In different topology mode, the mapping
between DIP switch setting and OML timeslot is also
different.
All ON
S10
4
Bit 1 and 2 control the grounding of the first E1;
Bit 3 and 4 controls the grounding of the second E.
ON: E1 transmission line grounded; OFF: E1
transmission line not grounded.
All ON
S11
4
Bit 1 and 2 control the grounding of the third E1;
Bit 3 and 4 controls the grounding of the fourth E1.
ON: E1 transmission line grounded;
OFF: E1 transmission line not grounded.
All ON