Rigid VHF Antennea?
 

I've had a few occasions where, under very heavy seas, my VHF antenna has
whipped forward and managed to catch the anemometer cups and get jammed,
causing me to lose wind speed data. Looking a photos of the masthead it
appears that the antenna is made by Metz. I'm very limited on where it can
be mounted and was wondering if there were rigid antenna that wouldn't
whip?

-- Geoff

Rigid VHF Antennea?
 

I have the same situation with my base loaded Shakespear VHF wipe.. It has
never caused problems with the wind instrument but it's only a matter of
time and the right (wrong) sea state.

I considered the possibility of a ridgid fiberglass antenna, even before I
stepped the mast. But then I considered the G forces that a ridgid antenna
would be subjected to. I wouldn't even attempt to figure all of this out,
but I can only imagine (having spent 5 min at the top of another boats 50 ft
mast in a moderate sea, in my younger days. ).

Maybe a rigid antenna is up to these forces. I don't know..

Steve
s/v Good Intentions

Rigid VHF Antennea?
 

We took an eight foot rigid 6db Shakespeare VHF antenna around the world
with no problems. Swee****er's masthead is 82' up, so while she perhaps
doesn't roll as sharply as a smaller boat with a 50' mast, there's a longer
lever.

Fintry's masthead is 36' off the water and she'll have three rigid VHF
antennas up there (she has two now).

Today I would choose Digital Antenna, Comrod, or (Bruce in Alaska's
recommendation), Morad, but don't worry about the antenna, even a
Shakespeare.


--
Jim Woodward
www.mvFintry.com


..
"Steve" wrote in message
...
I have the same situation with my base loaded Shakespear VHF wipe.. It has
never caused problems with the wind instrument but it's only a matter of
time and the right (wrong) sea state.

I considered the possibility of a ridgid fiberglass antenna, even before I
stepped the mast. But then I considered the G forces that a ridgid antenna
would be subjected to. I wouldn't even attempt to figure all of this out,
but I can only imagine (having spent 5 min at the top of another boats 50
ft
mast in a moderate sea, in my younger days. ).

Maybe a rigid antenna is up to these forces. I don't know..

Steve
s/v Good Intentions

Rigid VHF Antennea?
 

Thanks Jim,

Unless your tell me otherwise, I would still have reservation about the
constant flex of those sheetmetal 90 deg. mounting brackets that come with
both types of antennas.

In the end, I went with the base loaded wipe and the supplied mount bracket,
because I have a fixed span bridge that is very close to my mast height.. I
figure if the antenna hits, it would spring right back or the bracket would
bend over without any major damage. Yah! I know! I shouldn't cut it that
close and I don't, but there is always the possibility I miss calculated and
the 30" antenna would be the first to make contact.

Steve
s/v Good Intentions

Rigid VHF Antennea?
 

Sorry, I wasn't completely clear....

I agree completely about the sheet metal brackets. I fabbed a 1/4" aluminum
plate for the top of Swee****er's mast that held the wind instruments,
Windex, lights, and antenna -- so the antenna base, which had a 1"-14 female
thread, was bolted through the plate with a piece of threaded rod and a nut
(I couldn't find a stainless 1"-14 bolt). No appreciable flex there....




--
Jim Woodward
www.mvFintry.com


..

"Steve" wrote in message
...
Thanks Jim,

Unless your tell me otherwise, I would still have reservation about the
constant flex of those sheetmetal 90 deg. mounting brackets that come with
both types of antennas.

In the end, I went with the base loaded wipe and the supplied mount
bracket,
because I have a fixed span bridge that is very close to my mast height..
I
figure if the antenna hits, it would spring right back or the bracket
would
bend over without any major damage. Yah! I know! I shouldn't cut it that
close and I don't, but there is always the possibility I miss calculated
and
the 30" antenna would be the first to make contact.

Steve
s/v Good Intentions

Rigid VHF Antennea?
 

On Wed, 12 Nov 2003 14:38:41 GMT, "Geoffrey W. Schultz"
wrote:

I've had a few occasions where, under very heavy seas, my VHF antenna has
whipped forward and managed to catch the anemometer cups and get jammed,
causing me to lose wind speed data. Looking a photos of the masthead it
appears that the antenna is made by Metz. I'm very limited on where it can
be mounted and was wondering if there were rigid antenna that wouldn't
whip?

A good quality fiberglass antenna has absolutely no problem with this,
pretty common around here.

I would recommend

Comrod www.comrod.com (Norwegian)

or

Celwave (now AC Marine) CX-series (Danish)

www.acmarine.dk


/Marcus

--
Marcus AAkesson
Gothenburg Callsigns: SM6XFN & SB4779
Sweden
Keep the world clean - no HTML in news or mail !

Rigid VHF Antennea?
 

In article ,
"Geoffrey W. Schultz" wrote:

I've had a few occasions where, under very heavy seas, my VHF antenna has
whipped forward and managed to catch the anemometer cups and get jammed,
causing me to lose wind speed data. Looking a photos of the masthead it
appears that the antenna is made by Metz. I'm very limited on where it can
be mounted and was wondering if there were rigid antenna that wouldn't
whip?

-- Geoff

an even better idea is to get rid of the moving plastic aloft
and go with an ultrasonic wind sensor which gets speed and
direction with *no* moving parts.

-mo