GE MDS 4710M, Техническое руководство

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MDS 05-6399A01, Rev. E MDS™ Master Station 21
Table 3-1. Signal Loss in Coaxial Cables (at 900 MHz)
Cable Type
10 Feet
(3 Meters)
50 Feet
(15 Meters)
100 Feet
(30.5 Me-
ters)
200 Feet
(61 Meters)
RG-8A/U
0.85 dB 4.27 dB 8.54 dB 17.08 dB
1/2 inch HELIAX
0.23 dB 1.15 dB 2.29 dB 4.58 dB
7/8 inch HELIAX
0.13 dB 0.64 dB 1.28 dB 2.56 dB
1-1/4 inch HELIAX
0.10 dB 0.48 dB 0.95 dB 1.90 dB
1-5/8 inch HELIAX
0.08 dB 0.40 dB 0.80 dB 1.60 dB
Table 3-2. Signal Loss in Coaxial Cables (at 400 MHz)
Cable Type 10 Feet
(3 Meters)
50 Feet
(15 Me-
ters) 100 Feet
(30.5 Me-
ters)
200 Feet
(61 Meters)
RG-8A/U
0.51 dB 2.53 dB 5.07 dB 10.14 dB
1/2 inch HELIAX
0.12 dB 0.76 dB 1.51 dB 3.02 dB
7/8 inch HELIAX
0.08 dB 0.42 dB 0.83 dB 1.66 dB
1-1/4 inch HELIAX
0.06 dB 0.31 dB 0.62 dB 1.24 dB
1-5/8 inch HELIAX
0.05 dB 0.26 dB 0.52 dB 1.04 dB
3.5 Grounding Considerations
To minimize the chance of damage to the radio and connected equipment, a safety ground (NEC
Class 2 compliant) is recommended which bonds the Master Station, antenna system, and con-
nected data equipment to a single-point ground, keeping all ground leads as short as possible.
The Master Station should be grounded using the #6-32 screw and star washer provided for this
purpose on the rear panel.
The use of a lightning protector is also recommended where the antenna cable enters the equip-
ment building; bond the protector to the tower/mast ground, if applicable. All grounds and ca-
bling must comply with applicable codes and regulations.
Figure 3-2. Rear Panel Grounding Screw