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Discussion Starter #1
I'm about to install a CB on my JK and I'm toying with the antenna placement, one of the options I am considering is the tire carrier, but instead of mounting the antenna to the base on the tailgate I am thinking about using angle iron to raise it above the spare tire. Below is a picture of what I have in mind, the red part would be the metal base, the black line the antenna.
Would this be a good option?
Would a need a NGP antenna? or, a regular one?
 

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I don't think you will have any issues with placement, especially if you have a decent radio. I doubt it would fit in a standard garage if you used a firestick or anything similar. Would stink to have to remove the antenna every time you pulled in.
 

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That looks like a fine location Art. No ground plane antenna doesn't really matter too much for CB however it is important for choosing a VHF ham antenna. Firesticks are really tricky to tune and are very sensitive to placement. I've had the best luck with the Wilson Trucker CB antenna.
 

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Discussion Starter #4
I don't think you will have any issues with placement, especially if you have a decent radio. I doubt it would fit in a standard garage if you used a firestick or anything similar. Would stink to have to remove the antenna every time you pulled in.
Thanks. I'm OK having to remove it, I don't use the CB in town so it will stay off most of the time.

That looks like a fine location Art. No ground plane antenna doesn't really matter too much for CB however it is important for choosing a VHF ham antenna. Firesticks are really tricky to tune and are very sensitive to placement. I've had the best luck with the Wilson Trucker CB antenna.
Thanks John, I just placed the order for the Wilson Trucker. I been meaning to get a HAM license but keep putting it off, I should make it a point o do it after the holidays.
 

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Thanks. I'm OK having to remove it, I don't use the CB in town so it will stay off most of the time.


Thanks John, I just placed the order for the Wilson Trucker. I been meaning to get a HAM license but keep putting it off, I should make it a point o do it after the holidays.
I was told that you don't have to learn morse code anymore. I think that was probably holding a lot of people back LOL. Who want's to learn morse anyway :p
 

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Hmmm - I wonder if I posted this before?

Anyone still curious about antennas?
Here are a couple of links to read written by pretty smart guys.

Jeep antenna placement:
https://www.jk-forum.com/forums/jk-cb-ham-radios-128/here-where-you-should-mount-your-cb-ham-antennas-your-jeep-227276
IMO, for a CB it won't matter too much. For 2 meter/VHF is it more important.
Antenna mounts:
http://www.hamradio.me/antennas/nmo-mobile-antenna-mount-options.html

So, what I use for my CB is nearly exactly like Art’s with a dedicated ground wire to the Jeep chassis. My antenna is a no-name top-coil steel whip. Never found the brand as it came with the Jeep. Works very good with a very low SWR.
For my Ham setup I use a driver’s side NMO fender mount about 2’ from the A pillar and is shown in the link.
PaulW KEOVZC
 

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Discussion Starter #10
I read the article you linked on JK-forum when doing my research, this really stuck:
6 DO NOT PUT YOUR ANTENNA BETWEEN THE TAIL GATE AND THE SPARE TIRE
7 DO NOT PUT YOUR ANTENNA BETWEEN THE TAIL GATE AND THE SPARE TIRE
8 Just to make sure you are reading this correctly DO NOT PUT YOUR ANTENNA BETWEEN THE TAIL GATE AND THE SPARE TIRE. Read below for a more detailed explanation on this.
It is how I thought to mount it high on the carrier. I'm reading a good ground to the mounting point, the aftermarket tire carrier is all metal and bolted directly to the tub trough the hinges, but I have a ground strap on stand by. For the antenna I went with the Wilson Trucker on John's recommendation.
 

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Any mass of metal near an antenna could detune it and/or change its radiation pattern. With our Jeeps it's almost impossible to have an ideal antenna placement, as long as the SWR is 2.0 or less the radio should be happy. Where Art installed his Wilson is about as good as it gets. For an RF ground I used an aluminum strap from my tailgate to the aluminum corner guard (GenRight tub armor.) John, WB5THT.
 

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True, with my vhf antenna 2' from the A pillar I get a bit over 1 SWR at 35 watts and 2+ SWR at 75 watts. My SWR meter tells me the cause is because of degradation of the reflected signal because of being too close to the A pillar.
The mass of metal at the back of the Jeep degrades the signal. This is why my top load coil is so good with my carrier mount. Guys using the generic fiberglass antenna mounted the same way get a resulting less signal strength due to how the antenna works where the radiated signal is distributed over the length rather than the top above the coil. Still not a big deal for a 5 watt CB radio not designed for long range communication.
PaulW KEOVZC
 

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True, with my vhf antenna 2' from the A pillar I get a bit over 1 SWR at 35 watts and 2+ SWR at 75 watts. My SWR meter tells me the cause is because of degradation of the reflected signal because of being too close to the A pillar.
The mass of metal at the back of the Jeep degrades the signal. This is why my top load coil is so good with my carrier mount. Guys using the generic fiberglass antenna mounted the same way get a resulting less signal strength due to how the antenna works where the radiated signal is distributed over the length rather than the top above the coil. Still not a big deal for a 5 watt CB radio not designed for long range communication.
PaulW KEOVZC

Either your SWR meter is malfunctioning or you are interpreting the results incorrectly. SWR is constant at a particular frequency regardless of power. That is unless there is so much power you have voltage breakdown, corona, or whatever. Not likely with 75 Watts. Also, the bulk of the radiation from a top-loaded antenna is from the lower section of the antenna where the current is high and relatively constant along the length up to the loading coil. Current above the coil tapers to zero rapidly and contributes little additional radiation.
 

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Two different antennas one degrades at 75W due to reflect signal and top load does not.
If you think an antenna next to a metal object does not have signal degradation you are mistaken.
 

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My point is that VSWR does not change with power. I flagged this because you said you get close to 1.0:1 at 35 Watts and over 2.0:1 at 75 Watts. This did not make any sense. Apparently you were talking about two different antennas, one which happened to be measured at 35 Watts, and the other at 75 Watts (not that power level makes any difference). You are of course correct that placing the antenna near a metal object (or even a non-metal object in some circumstances) will affect performance.
 
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