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C

capteric36@sbcglobal.net

Wed, Dec 13, 2006 7:22 PM

I have decided to use a Power Over Ethernet unit
for WIFI. I will be able to put the antenna at the
top of my 40 foot mast which will add to the
range.

I wonder if there is such a thing as a Power Over
Ethernet device for a cell phone/
That would be the best way to get the signal to
the top of the mast, no long coax losses etc.

Does anybody know of an Ethernet connected
"Aircard" type device?

Eric Thompson
S/V Procrastinator
South San Francisco
capteric36@sbcglobal.net

I have decided to use a Power Over Ethernet unit for WIFI. I will be able to put the antenna at the top of my 40 foot mast which will add to the range. I wonder if there is such a thing as a Power Over Ethernet device for a cell phone/ That would be the best way to get the signal to the top of the mast, no long coax losses etc. Does anybody know of an Ethernet connected "Aircard" type device? Eric Thompson S/V Procrastinator South San Francisco capteric36@sbcglobal.net

SD

Steven Dubnoff

Wed, Dec 13, 2006 7:44 PM

At 11:22 AM 12/13/2006, you wrote:

I have decided to use a Power Over Ethernet unit
for WIFI. I will be able to put the antenna at the
top of my 40 foot mast which will add to the
range.

For an explanation of why height does not matter, see this:

http://preview.tinyurl.com/nnycz

Extra antenna height doesn't get you much because the absolute range over
water of a 200mw wifi signal on a 9db omni antenna is about 2 miles. With
the antenna at 10' the horizon is twice that far. Anything much higher than
the Bimini frame makes no real improvement. In some cases it could actually
work against you. Many marinas use sectorized antennas with narrow vertical
patterns and aim them down towards the end of the outer docks to get maximum
signal within the marina and minimize the spread to boats outside. If you
are anchored off the marina the antenna can be to high to be in the sweet
part of the beam.

Best,

Steve

Steve Dubnoff
1966 Willard Pilothouse
www.mvnereid.com
sdubnoff@circlesys.com

At 11:22 AM 12/13/2006, you wrote: > I have decided to use a Power Over Ethernet unit >for WIFI. I will be able to put the antenna at the >top of my 40 foot mast which will add to the >range. For an explanation of why height does not matter, see this: http://preview.tinyurl.com/nnycz >>> Extra antenna height doesn't get you much because the absolute range over water of a 200mw wifi signal on a 9db omni antenna is about 2 miles. With the antenna at 10' the horizon is twice that far. Anything much higher than the Bimini frame makes no real improvement. In some cases it could actually work against you. Many marinas use sectorized antennas with narrow vertical patterns and aim them down towards the end of the outer docks to get maximum signal within the marina and minimize the spread to boats outside. If you are anchored off the marina the antenna can be to high to be in the sweet part of the beam. >>> Best, Steve Steve Dubnoff 1966 Willard Pilothouse www.mvnereid.com sdubnoff@circlesys.com

JS

Jeffrey Siegel

Wed, Dec 13, 2006 10:30 PM

Extra antenna height doesn't get you much...

Anything much higher than the Bimini frame makes no
real improvement...

Those two things say different things - and they're both correct.

WiFi is a line-of-sight type of signal. It doesn't pass through things very
easily. Getting above the things around you will definitely help your
signal get out. It is true, however, that once you are above everything
else, you don't need to be any higher.

Even at anchor, your own boat can get in the signal's way if the antenna
isn't mounted high enough. At a marina, all the boats around you will cause
interference and height is usually more important.

================
Jeffrey Siegel
M/V aCappella
DeFever 53PH
W1ACA/WDB4350
Castine, Maine

> Extra antenna height doesn't get you much... > > Anything much higher than the Bimini frame makes no > real improvement... Those two things say different things - and they're both correct. WiFi is a line-of-sight type of signal. It doesn't pass through things very easily. Getting above the things around you will definitely help your signal get out. It is true, however, that once you are above everything else, you don't need to be any higher. Even at anchor, your own boat can get in the signal's way if the antenna isn't mounted high enough. At a marina, all the boats around you will cause interference and height is usually more important. ================ Jeffrey Siegel M/V aCappella DeFever 53PH W1ACA/WDB4350 Castine, Maine

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