Nortel BTR 2400, Руководство по установке

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1-10 BTR 2400 Release 1.1
411-1333-200 Preliminary July 1998
Installing the BTR 2400
Installation is performed in three separate operations:
• adjusting antenna polarity
• installing the tower equipment
• installing the indoor equipment
Adjusting Antenna Polarity
The polarity of the transmit and receive signals at the antenna are separated
by 90
°
. Polarity reversal is accomplished by separating the antenna from the
radio and rotating 180
°
, as shown in Figures 1-8 and 1-9. Horizontal and
vertical polarity are marked on the antenna.
Adjust the BTR antenna’s polarity as follows:
Ensure that you adjust polarity at the base station prior to mounting the
BTR 2400 to the pole.
Remember that you need to adjust the polarity and alignment of the
associated CTR 2400s if you adjust the BTR 2400’s polarity and
alignment.
1. Remove the eight (8) socket head cap screws (# 8-32 UNC) on the
antenna flange. There are four on top and four on the bottom of the
antenna flange. Remove the lock and flat washers. See Figures 1-3,
1-4, 1-15 and 1-16.
2. Gently remove the antenna and turn it 180°.
3. Align the antenna with the two dowel pins that act as an index.
4. Place the flat washer against the antenna flange, followed by the lock
washer and then the screw.
5. Use an Allen wrench # 8 to hard tighten the socket head cap screw to a
maximum of 28 inch-pounds torque.
6. Complete steps 4 and 5 for all eight socket head cap screws.
7. Ensure that the screw is inserted at the top of the antenna to prevent water
entering the antenna. However, loosen it halfway. The bottom screw is
removed to allow condensation to drain from the antenna. See Figure 1-3.