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Technetix Group Limited
Rev.1.0.1_0217
5.3 Upstream connection
The DBTX-A-1 is a dual module and has 2 upstream laser board slots. In the case of a DBD or DBE you can use the
2nd slot for a secondary laser or, when configured as a hybrid mixture, you can use a combining board (DBLB-CB-1) to
combine the RF from the secondary downstream feed over a single laser.
Connect the upstream laser to the pigtail or WDM module.
Remove the cover from the transmitter module so that the slots are visible.
A test point is located on all laser boards, this will align your Optical Modulation Index (OMI) to a satisfactory level.
Depending on the number of upstream channels, you can theoretically divide the 100% OMI available over the
respective channels. The higher the OMI percentage, the better your uplink. The upstream RF level can be measured
by using an MCX to F-female adapter (DBLB-TP-CON) connected to a spectrum analyzer.
DBLB testpoint (dBmV)
DBLB testpoint (dBµV)
OMI (%)
20
80
10
19
79
8.9
18
78
7.9
17
77
7.1
16
76
6.3
15
75
5.6
14
74
5.0
13
73
4.5
12
72
4.0
11
71
3.5
10
70
3.2
9
69
2.8
8
68
2.5
7
67
2.2
6
66
2.0
5
65
1.8
4
64
1.6
3
63
1.4
2
62
1.3
1
61
1.1
0
60
1
Содержание DBD-1200
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