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3' and 4" VHF antenna range

Old 10-20-2011, 08:28 AM
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Default 3' and 4" VHF antenna range

In tried searching, but the terms are too common. Im looking to mount a VHF antenna to thentop of my t-top. I would of course want a 8', but I keep my boat fully covered and a 8' won't work under the cover. If i can make a 4' work, that what I would like to go with. What type of range can i expect to see? Thanks.
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Old 10-20-2011, 08:57 AM
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Old 10-20-2011, 09:02 AM
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My boss went with a 4' on his new hard top. After his first offshore trip (25 miles) and not getting any response on the VHF he made the switch to an 8 footer. He has an extra sense of security now with the 8 footer. if you stay inshore you should be fine but they are not practical for offshore use.
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Old 10-20-2011, 09:23 AM
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I know it has been posted previously but if you haven't read it might answer some of your questions
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Old 10-20-2011, 06:18 PM
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There is no substitute for height if you are going offshore. That said, if you stay near shore, you can get away with a shorter one.

I'm using the Metz 3' SS and it works as well as the 4' Shakespeare that it replaced. Maybe a setup with the 3' SS on a 4' extension would be a compromise??
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Old 10-20-2011, 11:33 PM
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Any reason why a good 8ft 6db antenna on a SS swing-down ratchet mount would not fit under the cover? Just too long?
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Old 10-21-2011, 07:53 AM
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Cover goes over the t-top and is pretty snug.
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Old 10-21-2011, 04:24 PM
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Consider an 8 footer mounted on a vertical support to your T-Top as high as you can and yet still fold down the antenna to prevent cover interference. That way you get optimum gain and decent Line of Sight. 3 to 4 footer if it doesn't interfere with cover but mounted up top should be almost as good as the former. Line of Sight and Gain are neck and neck for most influencing your range.
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Old 10-22-2011, 01:27 PM
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The difference in effective range, due to differences in antenna height (at least on a small boat), is negligible. As you're in a small boat, you'll want to be careful regards a given antenna's gain (expressed in deciBels or dB). Stay within the 0 dB to 3 dB range. Finally, make sure that your antenna is located no less than three or four feet from the radio itself. In my opinion, Morad makes the best marine antennas.
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Old 10-24-2011, 11:03 AM
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Roughly a mile or less difference in range per the calculation. You never know when that might matter. Mounted up high, it probably wont be significant. I had a 4' mounted on the gunnel of a smaller boat and found it sometimes was shielded by larger waves and lost the signal in a trough.
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