Installation of the ADU
98-166784-A
Chapter 3: Installation
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Install
ation
3.3.5
Alternative ADU cable
In the ADU cable, the maximum allowed RF loss is 20 dB RF loss @ 1675 MHz.
You can verify the cable attenuation margin with the cable calibration, see on page 6-11
for more details.
The DC-resistance loop of the antenna cable must be maximum 0.9 Ohm. This is to ensure
the power requirements from ACU to the antenna and to ensure the performance of the
system. Preferably choose one of the cable types listed in the table below.
If you want to use an alternative ADU cable make sure that the following requirements are
fulfilled:
1. Check the data sheet from the cable supplier to verify the values:
The RF-attenuation and the DC-resistance are below the maximum values specified
below:
• ADU cable RF-attenuation at 1675 MHz: Max. 20 dB including connector.
• ADU cable modem-attenuation at 36 and 54 MHz: Max. 4 dB
• ADU cable loop DC-resistance max: 0.9 Ohm.
2. Respect the specified minimum bending radius, see the documentation from the cable
supplier. If this is not the case, the loss in the cable will increase.
Cable type
Thickness Absolute max. length (m) Absolute max. length (ft)
RG214
3/8”
50 m
160 ft
LMR-400-DB
0.405”
85 m
280 ft
LMR-600-50
1/2”
150 m
490 ft
LDF4.5-50 Andrew 5/8”
270 m
810 ft
Table 3-4: ADU cable types and maximum lengths
