Re: marine antenna choices?

Went with a Maxrad 8db unit. It's mounted on top of a shakespeare 12"
extension. The extension's stands about 2" above the Raymarine radome. At
the top of the extension I added a mylon 3/4" pipe thread female to 1" male
adapter. I then cut a hole in the middle of a 1" threaded cap and installed
the N-female end of the antenna through it.

The 3/4-1" adapter leaves enough room inside it to allow the N-male
connector to fit onto the antenna. The N-male connector cable is simply
tightened on to the base of the antenna directly. In order to minimize
twisting of the cable the adapter is spun onto the base first and then
backed up into the cap as it's tightened. I can just as easily keep the
pigtail cable loose enough to turn while tightening.

It's on a regular marine antenna base.

Signal strength on a nearby connection DOUBLED with this positioning.

The hassle was finding the right sort of way to attach the antenna to the
extension shaft. I'd looked into using regular PVC but each extra coupler
adds weight. That and the inside diameter of many fittings wouldn't
accomodate the N-Male connector. I was tempted to bore out the hole in the
extension shaft. It'd only need to be about 1/8" larger. But fearing
reduction of the mount's integrity sent me back out to the local hardware
store's plumbing section. I poked around in the parts drawers and
discovered the 3/4" to 1" adapter and it had more than enough room for the
N-male connector. I had to go to home despot to find a 1" threaded cap for
it though. Two local plumbing supply places had NONE of these parts with
threads, go figure.

Anyway, if you're looking to put an omni antenna on a marine mount this
might be a solution worth considering.

My next step will be to work out a way to easily swap the omni for a
directional. But I'm only going to bother with it if I discover the omni
giving me less-than-satisfactory results. I'd probably go with just a small
PVC extension using a 3/4" male to slip connection and a U-bolt style clamp.
I'd back a nut onto the extension to allow controlling the rotational angle.
The regular omni is just tightened down fully since rotation doesn't matter.

From the antenna it's an N-male to RP-SMA pigtail, with a 1 meter extension.
This leads to an RP-SMA to RP-TNC adapter on the back of the WRT54G that's
mounted up in the radar arch. This feeds an ethernet twisted pair to
another WRT54G in the lower cabin. I didn't use power-over-ethernet, I just
ran 12v power to them.

The only problem seems to be related to the firmware. If the shore SSID
comes and goes "too much" the firmware *sometimes* seems to get confused.
The symptom is it refuses to show anything but one or two SSIDs. If I soft
reboot the router it immediately shows all detected SSIDs during it's Site
Survey. This isn't easily repeatable, but it does seem to coincide with a
lot of wave action rocking the boat. I haven't yet dug into how the
firmware manages intermittent connections and reconnections.

Anyway, save for getting a 'sealed' enclosure I've now got wifi working
quite well on the boat.

-Bill Kearney