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Scanner / Receiver Antennas For discussion of any type of receiving antenna used by a scanner or receiver base, mobile or handheld.

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Old 01-22-2011, 3:44 PM
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Default CB antenna mounted deep inside pickup bed

I have my CB antenna mounted inside my truck like this.

I'm curious as to how much the signal weakens as a result to being half inside the bed?

I also have a 4 foot antenna to use. Would that be better?
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Old 01-22-2011, 9:50 PM
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Quote:
Originally Posted by BonziBuddy View Post
I have my CB antenna mounted inside my truck like this.

I'm curious as to how much the signal weakens as a result to being half inside the bed?

I also have a 4 foot antenna to use. Would that be better?
Hello BonziBuddy

I'd have to say that the mount you have in the picture should not affect your signal too much. IF you can I'd get a longer antenna but what you have now should work.

73

Ermin
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Old 01-22-2011, 10:47 PM
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I agree. That should be fine.
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Old 01-22-2011, 11:44 PM
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I have to disagree.
With part of the antenna being 'shielded' by it's 'other half', the metal of the vehicle, there will be a distinct loss in performance, and efficiency. You are also taking a chance of of that antenna 'shorting' out to the bed of the truck since the spring will allow it to beat against the side of the bed. Mounting it higher so that the base of the antenna is above the side of the bed will definitely make things 'better'.
I'm not a fan of helically wound antennas. So keeping that in mind, and if you can put up with the clatter and hitting things part, a longer and non-helically wound antenna would do better in my opinion.
- 'Doc
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Old 01-23-2011, 3:42 AM
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I agree a differnt location would indeed be better, but I doubt the signal that is lost from the current mount is so drastic that it is worth moving.

Just my 2 cents.
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Old 01-23-2011, 12:24 PM
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Mount it in CENTER of the roof.
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Old 01-23-2011, 1:27 PM
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The best mounting location for any antenna, no matter what frequency range is always dead center on the roof. The roof is clear of any obstructions. The body can be an attenuator when any antenna is mounted on the side of a vehicle. You will notice many of the newest automobile models are sporting roof mounted antennas and they are moved to the rear so as to avoid engine generated static. But it appears you park in a garage, the antenna should be mounted as high as possible on the bed and I would recommend using a spring at it's base if at all possible.
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Old 01-23-2011, 2:20 PM
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There WILL be some degradation with that mount. There will be capacitive coupling to ground at the high current end of the antenna. That would impact tuning, vswr, and antenna efficiency.
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Old 01-23-2011, 5:05 PM
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Of course the top, center of the roof is ideal, BUT i don't believe the current instal will pose too great of a problem.
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Old 01-23-2011, 11:14 PM
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Quote:
Originally Posted by ermin View Post
Hello BonziBuddy

I'd have to say that the mount you have in the picture should not affect your signal too much. IF you can I'd get a longer antenna but what you have now should work.

73

Ermin
I have a 4 foot version that I might switch back to.
Quote:
Originally Posted by LtDoc View Post
I have to disagree.
With part of the antenna being 'shielded' by it's 'other half', the metal of the vehicle, there will be a distinct loss in performance, and efficiency. You are also taking a chance of of that antenna 'shorting' out to the bed of the truck since the spring will allow it to beat against the side of the bed. Mounting it higher so that the base of the antenna is above the side of the bed will definitely make things 'better'.
I'm not a fan of helically wound antennas. So keeping that in mind, and if you can put up with the clatter and hitting things part, a longer and non-helically wound antenna would do better in my opinion.
- 'Doc
I figured that the CB frequency range wouldn't have a problem getting through the bed of the truck. It's also mostly compost plastic.

Quote:
Originally Posted by gewecke View Post
Mount it in CENTER of the roof.
n9zas

Quote:
Originally Posted by N1BHH View Post
The best mounting location for any antenna, no matter what frequency range is always dead center on the roof. The roof is clear of any obstructions. The body can be an attenuator when any antenna is mounted on the side of a vehicle. You will notice many of the newest automobile models are sporting roof mounted antennas and they are moved to the rear so as to avoid engine generated static. But it appears you park in a garage, the antenna should be mounted as high as possible on the bed and I would recommend using a spring at it's base if at all possible.

Quote:
Originally Posted by vinzep491 View Post
Of course the top, center of the roof is ideal, BUT i don't believe the current instal will pose too great of a problem.
I would love to but I already have 3 antennas in my roof!
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Old 01-24-2011, 12:15 AM
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Seeing your other antennas, I believe your current location is best to aviod interference
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Old 01-24-2011, 12:16 AM
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Nice and clean install by the way - do you have any pictures of the inside of your setup??
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Old 01-24-2011, 12:36 AM
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Awesome truck, awesome install. What's that middle antenna on the roof? Another VHF?

Lol, can't take the title of the thread seriously though... "mounted deep inside" Hmm...
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Old 01-24-2011, 5:00 AM
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I'd switch to a NMO CB antenna. Gave up on fiberglass a few years ago. Good luck whatever you do.
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Old 01-24-2011, 9:56 AM
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Those firestiks have been around forever and are ok performers-I would just raise the mount up to the top of the bed-the pattern of your transmit signal from that corner of the truck is already biased I think to the direction of the opposite front corner of the truck so you want that whole antenna to clear the metal bed -like zz0468 pointed out. If I had my way-102" steel whip springmounted at the bedside for the win
By the way-don't forget to provide a ground for that antenna via maybe a #6 groundwire to the metal of the bed (if you haven't already) as you said that the mountpoint is composite plastic.
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Last edited by ridgescan; 01-24-2011 at 10:00 AM..
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Old 01-24-2011, 11:15 AM
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On the subject of CB antennas, with over 40 yrs exp, your signal to wave ratio cannot be good with a mount in that position. In my exp antenna at least needs to be flush with the vehicle for best range, esp on transmit. If Shakesphere still makes antennas, their top loaded 48 incher was the bomb.
For just talking locally, on road, etc that location may be fine tho. Hope this helps, DC
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