BIRD 428B-83H-01-C-110, Инструкция по установке и эксплуатации

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TX RX Systems Inc. Manual 7-9487-3 05/05/11 Page 14
Installing the System
Installation of the TTA system should follow the
installation standards listed in
Figure 16, 17, and
18 . Lightning surge suppressors are incorporated
throughout the system; refer to items 6, 7, and 11
listed in figure 18 In addition, surge suppression is
also provided for all cable connections within the
tower top box. Proper grounding techniques must
be observed for these devices to perform properly.
See the following sections for specific installation
instructions.
Installing the Tower Top Box
Figure 19 shows some of the mechanical features
of the tower top box. Two mounting plates are
attached to the back of the box to allow for fasten-
ing to the tower.
Because of the varied tower types,
the customer must fabricate the interface brackets
between the tower frame and the box
. To install the
tower top box perform the following steps.
1) Mount a receiving antenna on the tower.
2) Run the main transmission cable as well as the
test transmission cable up the tower.
3) Mount the tower top box on the tower and con-
nect the antenna feedline, main transmission
line and test line to the box.
4) Connect the tower top box ground lug to a good
solid ground on the tower.
To insure stability, it is important to
fasten the box to the tower using all
mounting tabs. The box must be
mounted with the connectors and
moisture openings facing
downward
to prevent water entry. After connecting the main
transmission line, test line, and the antenna feed-
line, we recommend that the connections be tightly
wrapped with rubber splicing tape (see
Figure 20 ).
This will help prevent water entry into the cables.
Start the wraps on the cable several inches away
from the connector and wrap
towards the connec-
tor, this will prevent water from seeping in between
NOTE
Test
Diagnostic Cable
Ant Main
Test
RF Out
Trans
GTR 8000
Laptop
Signal Generator
Tower Top Box
CMU Front Panel
Test Port
Minimum length cables
Best possible sensitivity
Default Reserve Attenuation (3.0 dB)
Figure 15: Test equipment interconnection for “bench testing” of CMU system components.