Raymarine Apelco 5200, Руководство пользователя

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2.4.3
The coaxial cable from your VHF antenna is intended to be connected to the antenna jack on
the rear chassis using a PL259 VHF-type connector. The antenna cable may be cut to desired
length. If a longer cable length is required, RG-58
coaxial or equivalent cable may be
used for antenna runs up to a maximum of 50 feet. If the distance required is even greater,
then we recommend using low loss RG-213 or equivalent cable for the entire run in order to
avoid excessive losses in power output.
If the antenna connector is likely to be continuously exposed to the marine environment, pro-
tective coating of silicon grease (similar to Dow Corning DC-4) can always be applied to the
connector before mating it to the radio to help prevent corrosion. Any other extension or
adapters in the cable run should also be protected by silicon grease and then wrapped with a
weather-proofing tape.
2.4.4 Antenna Mounting Suggestions
The best radio in the world is useless without a good antenna location. Mounting the VHF
antenna properly is very important because how it is mounted will directly affect the perfor-
mance of your VHF radio. A standard VHF antenna which is designed for use aboard water
craft should be used.
There are several factors to consider so as to maximize the effective communication range of
the radio.
l
transmissions are essentially Line-of Sight, mount the antenna at the highest possible
location on the vessel. The location should also be free of obstructions in order to obtain
maximum range.
l
Use an antenna with the highest possible gain characteristics.
If you must extend the length of the coaxial cable between the antenna and the radio, use a cable
designed for the least amount of power loss over the entire cable length.
l
Keep the coaxial cable between the radio and antenna as short as possible.
Grounding
While special grounding is not generally required for VHF radiotelephone installations, it is a
good marine practice to properly ground all electronic equipment to the ship’s ground system.
The VHF5200 can be connected to ground by attaching a wire to the screw indicated in the
drawing below and then to the nearest ship’s ground connection point. The recommended
wire to be used for grounding is 0 AWG.
ANTENNA JACK
Fig. 2-7 TYPICAL GROUNDING METHODS
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