I currently have an old analog cell phone antenna at the top of my
mast on a trawler. Do not use the antenna any longer, and would like
to use the coax to mount a WiFi antenna to run to my onboard laptop.
My goal is better distances to AP. Anyone done something like this
successfully. My laptop has both PC Card slots and available USB 2.0
ports. I can find numerous claims on the internet, but would prefer to
find something that is a proven solution. Thanks

Pete

On Thu, 12 Mar 2009 07:58:54 -0400, wrote:

I currently have an old analog cell phone antenna at the top of my
mast on a trawler. Do not use the antenna any longer, and would like
to use the coax to mount a WiFi antenna to run to my onboard laptop.
My goal is better distances to AP. Anyone done something like this
successfully. My laptop has both PC Card slots and available USB 2.0
ports. I can find numerous claims on the internet, but would prefer to
find something that is a proven solution. Thanks

Pete

I currently use a USB WiFi amplified antenna hoisted on a flag halyard
about 20 ft. above the deck. It certainly gives me an improved signal
over the laptop's built in antenna located about 2 ft. above the
water..

I did, however, find that there is a practical limit to the length of
USB cable that can be used without some sort of amplifier in either
the line or the antenna.

Cheers,

Bruce
(bruceinbangkokatgmaildotcom)

In article ,
wrote:

I currently have an old analog cell phone antenna at the top of my
mast on a trawler. Do not use the antenna any longer, and would like
to use the coax to mount a WiFi antenna to run to my onboard laptop.
My goal is better distances to AP. Anyone done something like this
successfully. My laptop has both PC Card slots and available USB 2.0
ports. I can find numerous claims on the internet, but would prefer to
find something that is a proven solution. Thanks

Pete

Well considering that the frequencies involved (800 Mhz = Cell, 2400 Mhz=
WiFi) the losses in that Coax will rise significantly if you try and
push WiFi up it. You would be MUCH better off to run Ethernet up the
Mast, and mount a WiFi Client Access Device, with a good Omni Directional
Antenna on a SHORT Piece of Good Coax, and run the whole mess off POE.
(Power over Ethernet) I do this to extend my Network for the Close
Neighbors. (close = 10 Sq Miles) Works very well for "Me"....

--
Bruce in alaska
add path after fast to reply

Bruce In Bangkok wrote:
On Thu, 12 Mar 2009 07:58:54 -0400, wrote:

I currently have an old analog cell phone antenna at the top of my
mast on a trawler. Do not use the antenna any longer, and would like
to use the coax to mount a WiFi antenna to run to my onboard laptop.
My goal is better distances to AP. Anyone done something like this
successfully. My laptop has both PC Card slots and available USB 2.0
ports. I can find numerous claims on the internet, but would prefer to
find something that is a proven solution. Thanks

Pete

I currently use a USB WiFi amplified antenna hoisted on a flag halyard
about 20 ft. above the deck. It certainly gives me an improved signal
over the laptop's built in antenna located about 2 ft. above the
water..

I did, however, find that there is a practical limit to the length of
USB cable that can be used without some sort of amplifier in either
the line or the antenna.

Cheers,

Bruce
(bruceinbangkokatgmaildotcom)

Yes, the USB spec says 5m MAX. After that you need to go through a hub.
5m USB extender cables are basically a 5m lead with a single port hub
on the end. You can cascade up to 4 hubs if everything fully meets the
spec which limits you to an absolute max of 25 metres end to end.
Shorter *will* be better ;-)

Otherwise there are two part USB extenders that use Cat5 UTP cable for
the link and can go *much* further but they aren't cheap. Might be
worth it rather than the aggro Skip Gundlach had with his public wifi -
masthead access point -(ethernet)- local WiFi router lashup when he
was trying to avoid wires to the PC.

--
Ian Malcolm. London, ENGLAND. (NEWSGROUP REPLY PREFERRED)
ianm[at]the[dash]malcolms[dot]freeserve[dot]co[dot]uk
[at]=@, [dash]=- & [dot]=. *Warning* HTML & 32K emails -- NUL:

wrote in news:cnthr45bgr1bbrldc7u01npoupf2et3c8k@
4ax.com:

I currently have an old analog cell phone antenna at the top of my
mast on a trawler. Do not use the antenna any longer, and would like
to use the coax to mount a WiFi antenna to run to my onboard laptop.
My goal is better distances to AP. Anyone done something like this
successfully. My laptop has both PC Card slots and available USB 2.0
ports. I can find numerous claims on the internet, but would prefer to
find something that is a proven solution. Thanks

Pete


Pete, there's some serious problems with distance on the 2400 Mhz wifi
band. The main problem is everyone is on channels 6 and 11, the base
channels where the connections are made. If you live and boat in the
boondocks with none or a very limited number of stations, you CAN
install a remote access point at the top of the mast that will have
extended range. If you boat in Ft Lauderdale or any kind of affluent
populated area, there are so many interfering stations all blasting away
at once you'll notice little to no difference, at all, because of all
the jamming.

We've tried using higher powered (200 mw) commercial, not consumer, wifi
bridges and access points and I'm very disappointed in the real world
results, here in Charleston Harbor. The marina is STILL running only
20mw, the normal wifi power level, so the range is very lopsided. With
high power, they can hear you....but you can't hear them over the racket
of other stations nearby. Attenuation of the tiny transmitters was
specifically chosen in the wifi specifications to LIMIT range and reduce
interference on short-haul wifi circuits...100' or less.

Aha....but NOW we have a better solution!....use CELLULAR, instead.
Cellular (I call it sellular) was designed to reduce interference with
timing and frequency scanning schemes so you can be miles from the
tower, not 100', and still have service.

I hate sellphone-hobbled computing devices so rely on Bluetooth-
connected laptops and handheld tablets sellphone companies cannot
control...or hobble trying to raise revenues.

But, if I could make my OWN hotspot on wifi hooked to the cellular phone
system's internet service....I'd be eliminating the wifi interference
problem while carrying my own hotspot around to hook my wifi computers
to. The solution looks like this:

http://www.evdoinfo.com/content/view/2259/63/

The Cradlepoint MBR1000 is a "reasonably priced" router you plug either
a USB cellular modem or a laptop PCMCIA cellular card into the left side
of. The cellular modem THINKS it's plugged into a laptop as it finds
the software it's looking for and makes the connection, fooled by the
router. Once the link is connected, the router can then connect more
computers, tablets, and other wifi-connected devices than your boat will
ever have to the fooled USB modem on the cellular phone system.

No, it's not "free wifi"....but, it works very well. Mine sits in the
back window of my sedan and is connected to Cricket EVDO (unlimited for
$40/month, $35 if you buy phone service from them). I get about 1.2Kbps
down and 400Kbps up bandwidth...very respectable.

The cellular phone band isn't swamped with uncontrolled stations like
wifi. So, the modem has the same range as a cellular phone. On a boat,
I'd try installing a USB cable (Use Cat-5 Ethernet cable) from the top
of the mast to the router much lower down, probably very close to the
mast step to reduce losses in the USB cable that's not supposed to go
that far. Put the tiny USB modem in a sealed plastic box at the mast
head, running off its USB power in the cable. Instead of using the
Cradlepoint's wifi connection, I'd run an Ethernet cable from the router
straight to the chart table or wherever you're going to mount the
computer.

Now you have a cellular phone 50' in the air. Next time you're offshore
or way down some river in the country, ride your bosun's chair to the
mast head and see how well your cellular phone works from up there.
That would give you an indication of how well the cellular modem would
work up there. 10 miles offshore should be usable, far, far further
than any wifi extender scheme is ever going to operate. Any anchorage
should be well within cellular phone range. Does your phone operate in
the anchorages you use? If so, this data link will work, too.

Now connected, you can bypass expensive cellular minutes and long
distance charges, using VoIP software like Skype on the now-internet-
connected computer....video from its camera and all....

wrote in message
...
I currently have an old analog cell phone antenna at the top of my
mast on a trawler. Do not use the antenna any longer, and would like
to use the coax to mount a WiFi antenna to run to my onboard laptop.

Won't work. The frequencies used are different. So is the wire. That and
the higher frequencies used for wifi mean any distance from the radio to the
antenna will GREATLY degrade the signal. Even with using the right cabling
you still want it VERY short.

Personally, after rigging up an antenna with the access point directly
beneath it inside the radar arch, I found it wasn't worth the hassles of
trying to find an open network all the time. That and when you're swinging
on anchor the signals tend to fade in/out often enough to make it nearly
impossible to do anything for more than a minute or two.

My solution was to get a wifi router that supports plugging in a cell phone
data card. I use a linksys WRT54G3G router and a Verizon PCMCIA card.
Works great, works every time with no fishing around for signals.

-Bill Kearney