User Guide Part 2

Installing the RBS Main Unit Working with the GPS
92-F0423-1 Ericsson Proprietary 4-13
Daisy Chaining the GPS
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Figure 4–9 GPS Daisy Chaining Diagram
Steps
To daisy chain the GPS
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CAUTION
If the connections to the 1PPS+ and 1PPS– pins on the GPS daughter
cards are switched in a daisy-chained configuration, some or all CDMA
modules will not process calls. For more information, see
“Troubleshooting a Daisy-Chained GPS Signal” on page 7-19.
From
GPS
Receiver
Optional Shield GND
Optional Shield GND
Blk
3 (RX+)
2 (RX-)
5 (TX+)
4 (TX-)
11 (1pps+)
12 (1pps-)
1 (PWR)
9 (GND)
Red
Blu
Grn
Gry
Yel
Vio
Org
GPS
7
8
6
5
9
10
4
3
2
1
6
5
4
3
2
1
6
5
4
3
2
1
6
5
4
3
2
1
7
8
9
10
TX+
TX-
RX+
RX-
1pps+
1pps-
TX+
TX-
RX+
RX-
1pps+
1pps-
PWR
GND
GPS
6
5
4
3
2
1
6
5
4
3
2
1
7
8
9
10
7
8
9
10
TX+
TX-
RX+
RX-
1pps+
1pps-
TX+
TX-
RX+
RX-
1pps+
1pps-
PWR
GND
7
8
9
10