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Lucky7
New member
Username: Lucky7

Post Number: 4
Registered: 10-2005
Posted on Wednesday, October 29, 2008 - 10:01 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

I have a Wilson 5000 thru the roof mount, and I just purchased a 91 chevy hightop. Can I mount the wilson in the fiberglass roof and then just run a grounding strap to it or should I find another antenna and location?
Tomorrow will be yesterday two days from now!
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Tech237
Moderator
Username: Tech237

Post Number: 1078
Registered: 4-2004
Posted on Wednesday, October 29, 2008 - 6:04 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

FInd another location for any thru roof antenna. Not only will it cuase stress on the fibreglass that may lead to failure. but unless you actually place a 3ft x 3ft sheet of aluminium or similar metal under the roof at the mounting point you are going to have groundplane issues that can cause bad antenna matching and efficiency.
Simon
Tech237
N7AUS

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Hyperno_1979
Advanced Member
Username: Hyperno_1979

Post Number: 772
Registered: 12-2005


Posted on Friday, October 31, 2008 - 4:25 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Simon, maybe you can fill in the blanks here. Why not use a 27mhz marine antenna? I have seen some of them advertised that are supposed to work on fibreglass boats without a groundplane. So in theory should work on a fibreglass car. As i don't own a boat of any description i can only offer this as a possible solution. Help Simon.
CEFFFCEF
Bob
CEF703/CVC26
703 New South Wales
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Tech237
Moderator
Username: Tech237

Post Number: 1079
Registered: 4-2004
Posted on Friday, October 31, 2008 - 9:33 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Several reasons Bob.

Firstly they are cutt to resonate around 27,88Mhz so would be short on CB frequencies. Yes at a pinch they would work.

2)Height - the smallest 27Mhz marine antenna is 9ft tall. Mount that on a roof and you come up with problems on bridges, drive thrus etc. The don't give like a 9ft stainless will.

3) Thickness of the fibreglass roof. Boat hulls are several times thicker than the average truck bed roof, and therefore many times stronger.

4) as there is no 27MHz Marine here in the USA availability becomes and issue too.


n theory, yes you could make it work, but may have some problems to overcome. If anyone wants to experiment I do have plans of a 27MHz Marine antenna (that canand was home made) that I used to make and sell. PM me and I'll email them to you.
Simon
Tech237
N7AUS

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Hyperno_1979
Advanced Member
Username: Hyperno_1979

Post Number: 779
Registered: 12-2005


Posted on Saturday, November 01, 2008 - 10:43 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Thanks mate,
As i said i have never owned a boat but just offering a suggestion. Also didn't know you guys don't have 27 mhz marine.
Regards,
Bob.
CEFFFCEF
Bob
CEF703/CVC26
703 New South Wales
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Lucky7
New member
Username: Lucky7

Post Number: 7
Registered: 10-2005
Posted on Monday, November 03, 2008 - 7:39 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Thanks for all the info, I have decided to go with the Predator 10K off the rear of the body at the roof line. I think it will do the job just right!
Tomorrow will be yesterday two days from now!

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