set up many ISP's in the
Caribbean over the years.
always had complaints from sailboats regarding signal strength even though the signal
was usable from up to a mile away via
dinghy. Issues were usually antenna placement and the occasional "dead" zone. (yes they occur despite the denials, always conducted a signal
survey when setting up a
commercial wifi ISP so we knew where they were).
1. In a sailboat
salon, which is usually at or below water line it is just not going to work.
My multiwatt transmitters can beacon you but your 17mW return signal just doesn't reach from virtually underwater. I even ran receive amps but without a decent antenna and some kick it just isn't reliable. Thus, the need for external amps and antennas.
2. I have used Linksys routers with DDWRT firmware in repeater mode for ages. They are
cheap, reliable, will put out up to 250mW in native mode, and will repeat the signal so all you have to do is set the bloody thing somewhere with a clear view of the ISP and it will translate their wireless signal onto your own private wireless net. All it needs is a 12Volt power wire. NO ether
cables or coax.
I had one survive for 3 years in a plastic bag on the boom in
south america.
I have run them up the mast on a
halyard.
I have even placed them ashore in a vehicle parked between the ISP and my
boat.
This works because the DDWRT firmware will also "daisy chain" so a friend on a
boat with better
reception can act as a repeater for you. The DDWRT 54GL (available from walmart by special order, $50) also has external antenna connectors so you can
add a beam or omni external for a few more dB gain.
3. It is amazing what will interfere with a wifi signal. I have noticed substantial differences in signal level just by moving the antenna from inside the shrouds to outside the shrouds at the same height and heading. Some folks had great results putting the wireless device in a
cheap chinese colander and making a beam out of it.
My experience has been if you can't see the antenna without obstruction, including
even a shroud wire, then sooner or later you will have problems in fringe areas.
The other thing to consider is most good wifi coverage is in
mooring fields or relatively
dense
anchorages. That masthead mount is above both your own boats
interference and most of your neighbors. The spreaders not so well. Your own mast and a row of 50 others may be in the way along with the grounded shrouds of all those other boats. (or wait till that
steel trawler anchors next to you and blanks you entirely till
the
wind shifts).
If you decide to go low, i use a 120 degree beam antenna. Its not as sensitive to swing as a tighter 15 degree but still gives you some gain and the ability to aim through some of the interference. However, it is a pain in the backside if you swing a lot.
And i second the imho of coax up the mast is a loser. Yes, it works, but it is so much
more expensive and doesn't work near as well as a power over ethernet solution or
a repeater like i recommend to my customers. And coax
insulation degrades with moisture. Particularly at these frequencies. Yes I know, the manufacturer guarantees their coax won't absorb moisture. File that with the
government is here to help, the check is in the mail, and the 100 mpg carburetors.
cheers
gello