Raymarine ray240 Benutzerhandbuch

Chapter 3: Installation

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You should use a good quality VHF antenna, designed for marine use installed in 
accordance with the following:

• ensure that the antenna is connected to the radio before transmitting.
• Raymarine declares a Maximum Permissible Exposure (MPE) radius of 1.5 

meters (per OET Bulletin 65) for this system, assuming 25 watts output to an 
omnidirectional antenna of 3dBi gain or less.

• for watercraft with suitable structures, the antenna base must be at least 3.5 

meters above the main deck to meet the MPE for persons up to 2 meters tall.

• for watercraft without such structures, the antenna must be mounted so that 

its base is a minimum of 1.5 meters vertically from the heads of all persons.

• as high as possible and free from obstruction for maximum range. VHF 

transmission is essentially line-of-sight. 

• if you have to extend the length of the co-axial cable between the antenna 

and the radio, use one that is designed for minimum power loss over the cable 
length.

When planning the installation, consideration should be given to where cables 
are to be run:

• Try and avoid acute bends in cables.
• Secure and protect cables from physical damage and protect them 

from exposure to heat. Avoid running cable through bilges or door-
ways, or close to moving or hot objects.

• Where a cable passes through an exposed bulkhead or deck head, 

a water-tight feed-through should be used.