Raymarine Ray54E - Manual (Page 18)

8 Ray54E VHF Radio
2.7 Antenna Connections
The coaxial VHF antenna cable connects to the Ray54E antenna jack on the
rear panel using a PL259 VHF type connector. The antenna cable length can
be critical to performance. If you are uncertain, contact a professional
installer or call Raymarine Product Support. If a longer cable length is
required, RG-8x (50 ohm) marine coaxial cable or equivalent cable can be
used for runs up to a maximum of 50 feet. If the distance required is even
greater, Raymarine recommends using low loss RG-213 or equivalent cable
for the entire run to avoid excessive losses in power output.
If the antenna RF connector is likely to be exposed to the marine
environment, a protective coating of grease (Dow Corning DC-4 or similar)
can be applied to the connector before connecting it to the radio. Any other
extensions or adapters in the cable run should also be protected by silicon
grease and then wrapped with a waterproofing tape.
Antenna Mounting Suggestions
Mounting the VHF antenna properly is very important because it will
directly affect the performance of your VHF radio. Use a VHF antenna
designed for marine vessels.
Since VHF transmission is essentially line-of-sight, mount the antenna at a
location on the vessel that is free of obstruction to obtain maximum range.
If you must extend the length of the coaxial cable between the antenna and
the radio, use a coaxial cable designed for the least amount of power loss over
the entire cable length.
Antenna Mounting and EME Exposure
For optimal radio performance and minimal human exposure to radio
frequency electromagnetic energy, make sure the antenna is:
•
connected to the radio before transmitting
• properly mounted
• located where it will be away from people
• located at least 1.5 metres (5 feet) from the radio