CB Antenna Placement

I am going to be installing a 4' fire stik and was wondering were the best place would be?

I don’t have flairs, this is my DD so I don’t go wheeling on trails were I am going to be tarring things off.

I was thinking of the front pass fender on the side (about 12" lower then the stock antenna so it would be the same height). But I am afraid that the fender it self is not as strong as the rear. So if go through a car wash I don’t have my antenna ripped off. Or have my fender bent out. X

[FONT=&quot]How much more performance / range do you get when you run two antenna’s?[/FONT]

The best place to put a CB antenna is the center of the roof. Your CB signal will radiate equally in all directions. The farther away from any sort of signal interference, the better. If you need to put the antenna lower to use a garage or to avoid trail damage, the hood or tailgate are other common locations. Use an antenna spring to allow more flex.


The Firestik hood bracket is strong enough for a 3 - 4 foot antenna and use on the trails. Remove the antenna for car wash use.

Co-phased antennas are for big trucks. You will actually loose some range if you use two antennas on a Cherokee.

How do the antennas know they are on an XJ and not a big rig?

the best place is on the roof w/an egg mount. the draw back is overhead clearance (parking garages, drive-thru's and such).

I run a wilson silverload flexi on a magnet mount. not as stable at high speeds (in rare instances, a strong gust from passing trucks at highway speeds will knock it off). but other than that i have had exellent luck.

rule of thumb...the higher the antenna is mounted on the rig, the farther it will transmit.

How do the antennas know they are on an XJ and not a big rig?

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Because they will be too close to each other.

one on front one on back would be further apart than the width of any big rig.

razdrvr said:

How do the antennas know they are on an XJ and not a big rig?

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Because they are smarter than the XJ driver ?

razdrvr said:

one on front one on back would be further apart than the width of any big rig.

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GOOGLE co-phased CB antenna, do some research, and then tell us why two CB antennas on a Cherokee is pointless.

I never said that they were or were not pointless. I was just stating the 2 antennas could be place just as far apart on an XJ as a big rig. Is it pointless to have 2 on a big rig? I'm just asking questions, not trying to prove you wrong.

The only reason you would need two antennas is if you were pumping out over 150 watts and the power output would be shared by both low power (cheap) antennas, as well as attempting to get a better signal coverage without sticking an antenna high from on top of the roof. But you would have to use eight foot, full phase antennas at each side, which contradicts the purose of not wanting a single antenna on the roof hitting every low clearance location you go.

I have used a 300 watt pushbox using a single big Wilson mag mount whip and over powered anybody because not only did I have the lanier, I increased my modulation enough so it didn't squeel. Modulation is the volume at which your voice is broadcasted but is carried by the power output (watts) to get the distance coverage. A CB with good modulation settings can overpower (step on) another CB that has more watts but low modulation. The louder one always wins side by side.

Here is a good read on co phase antennas: http://www.signalengineering.com/ultimate/mobile_antennas.html

So getting back to the first post, you really don't want to place the CB antenna next to the radio antenna. That would cause too much swr (signal wave return) and can damage the CB's circuit finals, and maybe even the radio itself. CB antennas should always be placed at least three feet from other antennas if output is around 5 watts, and further if CB has more watts. Note this, some CBs have upper and lower side band channels which on some CBs are transmitted at 12- 25 watts compared to the legal 4 or 5 watts on the regular channels. So IMHO, the further from other antennas the better, along with the higher on the Jeep the better.

I use a Wilson Lil' Wil mag mount on my XJ's roof and a tweaked Cobra CB without a lanier (pushbox/signal amplifier) and it has never failed me for distance. So far I have been able to get heard as far as about a hundred miles parked near the top of Telescope Peak in Death Valley NP, and got response from a trucker with a heavily modded CB traveling on the 15 freeway. Now that is reasuring, with the thought of "what if" when I really need help, and alone, I know I could be heard from somebody who can contact the cavelry for me even if they can't reach me with their radios, but they can hear me.

[FONT=Arial, Helvetica, sans-serif]Here's a quote from the link above that "proves" the pointlessness of two sticks on our Jeeps:
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[FONT=Arial, Helvetica, sans-serif] Co-Phasing antennas simply means taking two identical antennas, mounting them on the vehicle and feeding them in-phase. One of the biggest misconception of radio operators is what kind of effect this has on the radiation pattern. Most people think that after you Co-Phase two mobile antennas, your signal will be strongest in line with the vehicle body (meaning the signal is strongest down the road straight in front of you and straight behind you also. This is the theoretical effect that you would get from co-phasing two omnidirectional antennas. However, to realize this effect you need to satisfy a couple of requirements. For one, a good earth ground with long (over a wavelength or so) radial wires is required. Secondly, at CB frequencies the closest you would be able to place these antennas are about 18 feet apart. Since it is impossible to satisfy these requirements, the effect of co-phasing is seriously diminished. Unfortunately, even the "Radio Shack Antenna Book" states that co-phasing two mobile antennas will produce a two directional signal. [/FONT]
[FONT=Arial, Helvetica, sans-serif] So then, is there any advantage to co-phasing two mobile antennas? Why yes, there is. Before we noted that the radiation pattern of a single antenna is "pulled" where there is the most metal vehicle body. You can see the pattern is not perfectly omnidirectional like we would expect it be. As we travel down the road, you will notice signal fade ("flutter" or "waver") from this uneven radiation pattern. Co-phasing two antennas will even out the pattern irregularities. Instead of making the pattern more two directional, it will make it more omnidirectional. Do not expect more "gain" from two antennas. Figure 3 shows how co-phased antennas clean up the radiation pattern. Read the section "Co-Phasing" for instructions on how to make a harness to feed your co-phased antennas. It best to get them as far apart as possible. The best way would be to mount one on the front bumper in the center and one on the back bumper in the center also. Most people think this looks silly (me included!) and mount one on each side of the vehicle.


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Am I totally misunderstanding something, that looks like proof that there is an advantage to having 2 sticks on an XJ or any car.

i have a single 5 foot firestick mounted on my rear bumper on the driver side...along with my cobra 29 LTD i get some pretty damn good range

razdrvr said:

Am I totally misunderstanding something, that looks like proof that there is an advantage to having 2 sticks on an XJ or any car.

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The pic only proves two antennas fixes the direction of the signal. But you would have to use full phase whips that are eight feet long. Also the power output is diminished by the two antennas being closer than the eighteen feet they need to be to be an improvement over the single antenna

Magus2727 said:

^^^^do you have problems going in and out of parking structures? What kind of lift do you have and what is the height from the ground to the top of the Antenna?

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i catch alot of tree's out on trails but other then that no i havent caught much other things...

just measured...92 inches to the top with 3 inches of lift and 31 inch swampers

Mine is on a bracket between the hood and fender on the left side.







I have yet to get my entenna from my storage unit in Vancouver, but in time it will arrive.....(my dad is coming up this weekend, if I bribe him with free booze, he might just bring it up.....)

I made a mount at the front of the Heep so it would lay down on the hood when going through trees. It looks redneck but works great. I can see it get whacked and it makes a good "tree feeler". I get super low SWR's, around 1.0.

Why did you choose to put it right in front of the driver. That thing would drive me nuts.

razdrvr said:

Why did you choose to put it right in front of the driver. That thing would drive me nuts.

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Just a conveinent spot, and I was in a hurry to get ready for a ride! I was going to change it later to the center or even the right but I ended up liking that set-up. My original intention was to put it in the stock radio antenna spot but couldn't work out a strong enough mounting system. I like the way it lays flat on the hood when pulled all the way over, almost no way to break it. I'm running the Firestick light duty spring.

Mine is mounted between the right side taillight and the rear quarter. Which I have recently found to be a bad idea considering I cracked my hard to find waggy taillights when the antenna caught a tree one night.