wrote in message
...
On Tue, 13 Oct 2009 22:24:06 -0400, "Steve"
wrote:

Hello,
I want to put an antenna on a -fiberglass- motorhome (class a) and I'm
not
sure about the no gound plane vs the regular mobile antenna choices. I
have
a ladder
rack on the back, and a luggage rack on top, but I'm not sure of how much
ground I can get from that.

I have a 102" whip laying around and I thought about mounting that to
the
back bumber with a homemade plastic 'standoff' at the top of the motorhome
to keep it from swinging.

Good idea, or no? (tree pruner is not what i want) but from the bumper I
can
use most of that 9' before it clears the roof on a fiberglass body.

Strange combo.


Mounting an antenna on the side or back of a motorhome can be
ineffective in some directions. You really need to have an antenna
as free of obstructions as possible.


Agreed but remember the body and roof are fiberglass on this motorhome. Non
conductive.


The best choice for a lack of ground plane is a set of dual antennas.
Something like this: click on dual antenna kit
http://www.firestik.com/CatalogFrame.htm


I've generally heard one antenna works better than two unless you can
seperate them more than is practical in -most- applications
but I could be wrong about that. The NGP antenna involes using your coax
length to match the swr, right?

My plan is to cut enough coax to reach from the whip mount to the radio, and
none for tuning the swr.

Thanks for the help, tnom, I only want to do this once so I figure to ask
questions first..maybe test
and tune along the way. I fugure the 102"will see right through most of the
coach, no?

73
Steve.

Thanks for the help, tnom, I only want to do this once so I figure to ask
questions first..maybe test
and tune along the way. I fugure the 102"will see right through most of the
coach, no?

73
Steve.

What metallic framing is just under the fiberglass. What wiring?
Any of this running parallel in close proximity to the antenna will
have an effect.

wrote in message
news

Thanks for the help, tnom, I only want to do this once so I figure to ask
questions first..maybe test
and tune along the way. I fugure the 102"will see right through most of
the
coach, no?

73
Steve.

What metallic framing is just under the fiberglass. What wiring?
Any of this running parallel in close proximity to the antenna will
have an effect.


Yeah that's the question and I won't know until I try it. My other concern
is overpass clearence with it. It already has a two foot
CB antenna on it and I ain't impressed, so I'm looking to upgrade. I'll
mostly use it on ssb ragchew.

73
Steve.

Instead of a 102" whip flying around,why not simply pick up a shakespear marine cb antenna that's designed to be used with fiberglass craft? It could be mirror-mounted then you're done!
N9ZAS

Instead of a 102" whip flying around,why not simply pick up a shakespear marine cb antenna that's designed to be used with fiberglass craft? It could be mirror-mounted then you're done! A marine antenna will perform nearly as well as that overgrown 102"! You can still mount it to your luggage rack too.
N9ZAS

On Tue, 13 Oct 2009 22:24:06 -0400, "Steve"
wrote in :

Hello,
I want to put an antenna on a -fiberglass- motorhome (class a) and I'm not
sure about the no gound plane vs the regular mobile antenna choices. I have
a ladder
rack on the back, and a luggage rack on top, but I'm not sure of how much
ground I can get from that.

I have a 102" whip laying around and I thought about mounting that to the
back bumber with a homemade plastic 'standoff' at the top of the motorhome
to keep it from swinging.

Good idea, or no? (tree pruner is not what i want) but from the bumper I can
use most of that 9' before it clears the roof on a fiberglass body.

Strange combo.


Try an electric fence standoff/insulator. They even come in different
lengths.

"Frank Gilliland" wrote in message
news
On Tue, 13 Oct 2009 22:24:06 -0400, "Steve"
wrote in :

Hello,
I want to put an antenna on a -fiberglass- motorhome (class a) and I'm
not
sure about the no gound plane vs the regular mobile antenna choices. I
have
a ladder
rack on the back, and a luggage rack on top, but I'm not sure of how much
ground I can get from that.

I have a 102" whip laying around and I thought about mounting that to
the
back bumber with a homemade plastic 'standoff' at the top of the motorhome
to keep it from swinging.

Good idea, or no? (tree pruner is not what i want) but from the bumper I
can
use most of that 9' before it clears the roof on a fiberglass body.

Strange combo.


Try an electric fence standoff/insulator. They even come in different
lengths.


Hello Frank, yeah something like that would work or something a bit more
flexable for when it bangs off of tree branches and such.
It will be late winter/early spring before I install it so I have time to
ponder on it, I'm sure I'll come up with something.

Do you like the 102" whip, or the 'no ground' antenna mounted to the ladder
for my application?

73
Steve.

On Fri, 6 Nov 2009 18:56:48 -0500, "Steve"
wrote in :


"Frank Gilliland" wrote in message
news
On Tue, 13 Oct 2009 22:24:06 -0400, "Steve"
wrote in :

Hello,
I want to put an antenna on a -fiberglass- motorhome (class a) and I'm
not
sure about the no gound plane vs the regular mobile antenna choices. I
have
a ladder
rack on the back, and a luggage rack on top, but I'm not sure of how much
ground I can get from that.

I have a 102" whip laying around and I thought about mounting that to
the
back bumber with a homemade plastic 'standoff' at the top of the motorhome
to keep it from swinging.

Good idea, or no? (tree pruner is not what i want) but from the bumper I
can
use most of that 9' before it clears the roof on a fiberglass body.

Strange combo.


Try an electric fence standoff/insulator. They even come in different
lengths.


Hello Frank, yeah something like that would work or something a bit more
flexable for when it bangs off of tree branches and such.
It will be late winter/early spring before I install it so I have time to
ponder on it, I'm sure I'll come up with something.

Do you like the 102" whip, or the 'no ground' antenna mounted to the ladder
for my application?


Beats me. The few 9' whips I've seen on RVs were bolted to the front
bumper. But anything you mount is going to hit something eventually.
And almost anything will work for local chatter under a mile, which
covers the vast majority of CB usage on the road. Once you park you
can screw on any stick that can be carried inside the RV and you don't
have to worry about hitting power lines. So it seems to me that a
whip-swapping system would give you the most bang for your buck. Heck,
if I had a two-piece 9' whip I could keep it stashed behind the seat
of my truck..... hmmm.....

"Frank Gilliland" wrote in message
...
On Fri, 6 Nov 2009 18:56:48 -0500, "Steve"
wrote in :
-snip-
Beats me. The few 9' whips I've seen on RVs were bolted to the front
bumper. But anything you mount is going to hit something eventually.
And almost anything will work for local chatter under a mile, which
covers the vast majority of CB usage on the road. Once you park you
can screw on any stick that can be carried inside the RV and you don't
have to worry about hitting power lines. So it seems to me that a
whip-swapping system would give you the most bang for your buck. Heck,
if I had a two-piece 9' whip I could keep it stashed behind the seat
of my truck..... hmmm.....


Hello Frank, you just gave me an idea. The motorhome already has a short CB
antenna on it (sucks) for portable comms so I might try an A-99 mounted to
the ladder rack just for 'parked at the site' comms. They're three sections
so I could store the top two sections inside the home when not in use. Like
you say...hmmm..

Thanks for your input, Frank.

73
Steve.

On Sun, 15 Nov 2009 08:39:44 -0500, "Steve"
wrote in :


"Frank Gilliland" wrote in message
.. .
On Fri, 6 Nov 2009 18:56:48 -0500, "Steve"
wrote in :
-snip-
Beats me. The few 9' whips I've seen on RVs were bolted to the front
bumper. But anything you mount is going to hit something eventually.
And almost anything will work for local chatter under a mile, which
covers the vast majority of CB usage on the road. Once you park you
can screw on any stick that can be carried inside the RV and you don't
have to worry about hitting power lines. So it seems to me that a
whip-swapping system would give you the most bang for your buck. Heck,
if I had a two-piece 9' whip I could keep it stashed behind the seat
of my truck..... hmmm.....


Hello Frank, you just gave me an idea. The motorhome already has a short CB
antenna on it (sucks) for portable comms so I might try an A-99 mounted to
the ladder rack just for 'parked at the site' comms. They're three sections
so I could store the top two sections inside the home when not in use. Like
you say...hmmm..

Thanks for your input, Frank.


Heck of an idea. Kinda wish I had thought of it myself. Just don't
forget that the A99 is a half-wave, so don't expect it to tune like it
does on the roof. You might have to spin those rings quite a ways
before you get a decent match.