Afar AR24027, Руководство оператора

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AR24027 Operator’s Manual
6-7
6.3.4 Cable Loss (Attenuation)
The AR24027 is housed in a watertight enclosure so that it may be mounted in very close proximity to
the antenna. Using short cables to connect the radio to the antenna reduces signal losses. Table 3.2
shows loss per 100 feet (30 meters) at 2.4 GHz for typical antenna cable types.
Table 3-2. Loss at 2.4 GHz for Standard Coaxial Cable Types
Cable Type Loss per 100 ft. (30 m)
RG-8 A/U 14.4 dB
Belden 9913 8.0 dB
LMR 195 19 dB
LMR 400 6.7 dB
To determine total cable loss for your installation, perform the following calculation:
For US units, multiply length in feet by the loss figure and divide by 100.
For metric units, multiply length in meters by the loss figure and divide by 30.
For example, for a 75-foot length of Belden 9913, the loss is:
6.3.5 Connector Loss
Loss is introduced with each pair of cable connectors. Attenuation losses of some standard cable
types are shown in the following table:
Connector type Loss per connector
N-Type 0.25 dB
SMA-Type 0.25 dB
The loss of each pair of connectors on all cables must be included to determine the total signal loss
(attenuation) between the radio and the antenna.
75 x 8.0
100
= 6.0 dB