I currently have a 2 meter antenna mounted on the 3rd brake light. It works well enough for now. I was wondering if it was possible to have two spare tire mounts so that I can run an antenna on each side of the spare. WIll they interfere with each other? I want one for 2 meter and the other for a CB that I am planning on getting soon.

Has anyone tried this? Does it work?

As always, TIA for any help.

 

My general understanding is that is may be good for long-haul truckers, but not great in off-road situations. The dual antenna design is great for signals to travel perpendicular to the plane created between the antennas (in other words, ahead of you and behind you), but not as great radiating along the plane (to either side)

Here is a article I found about it, with notes on proper setup:

h**p://www.cbradiomagazine.com/May%202007/Dual%20Antennas%20-%20looks%20aren%27t%20everything.htm

 

Many have put antennas pretty close to each other, like you speak of, and "say" they have no problem. As far as I'm concerned ANY metal, weather it be an antenna or not, if it's too close it will react.

People put dual antennas on either side of the cab in hopes that they are, what they call, "Phased" antennas. And yes, on a big rig, when there is enough "proper" space between them then yes, they will be phased. But usually on a car or any small vehicle there isn't enough distance for them to properly be phased. Some antenna companies dispute this but I'd have to see it to believe it.

As far as being too close on your tire mount. If you are talking about a foot or less I personally don't think I would do it. Guys have reported having swr problems just from the frame of the soft top being too close. I would feel much more comfortable with one on each end of the bumper instead. I'm sure people will jump in here and say no problem putting them that close, but in my opinion, I don't think it's a good idea.

Of course when it comes to antennas, many times things look good on paper, but until you try it you really never know. There are just too many variables. It just depends on how much effort you want to put into something to see "if" it will work. For the most part tho, a sign of if you put the antennas together too close is that you usually won't be able to get the swrs dialed in. That could be your first indication.

 

For what it's worth:

I run my CB antenna (Wilson 4 foot "flex") on a cooltech "gatemount" on the passenger side of my stock spare tire carrier. I run my VHF/UHF (CA-2X4 SR) on the same sort of mount on the driver's side of the stock tire carrier. This means that I have spacing of almost exactly 18 inches between them.

I haven't done enough in the way of actual tests to tell you if there's any real interference that occurs, but I can say that both my VHF and CB mountings seem to perform at least as well as most people's mobile rigs, and substantially better than many. I've been able to get the SWR on my CB down to 1.2

If you look closely at the pic (I know, not the best) you can see both the CB and the VHF/UHF.

 

I doubt you will have any issues as they will be running different bands, just make sure they don't touch while in use.

 

Tried it: No. Will it work: Yes.

As AK4Dave sais they should be farther apart. They will both work and you will be able to receive and transmit. The CB antenna mounted close to the VHF antenna will affect the radiation pattern of the VHF antenna. And vice versa. Will you notice a null spot? Probably not.

I personally would mount them as far apart as possible. Would you ever install a HF antenna? I have a HF on the driver side, CB in the center and VHF/UHF on the passenger side. I feel pangs of guilt about those. I think about the other two antennas anytime I am getting ready to use any one of them.

Any radio install on a JK is about compromises. Try an install/configuration. If you aren't happy with it, move one or both.

 

and use it to do everything!

thats my thought right now, but they are soooo big, and I can see some butt-clown hitting me in the parking lot (happened before jacked up ym tire carrier) and now I'm out several hundred bucks in antenna as well as whatever else they caused...

 

Currently running a metz off of the 3rd brake light, which I would have to move. Any one have any luck with a hood lip mount instead then? That should give them enough separation if the 2 meter is a wavelength away or so. With the CB antenna, I don't guess there's any mounting solution that would do that for it. I want to keep the 2 meter as far away from the cab as possible, since it puts out 75 watts as opposed to the CB's 4.

I'd hate to start another thread just for that, so I am waiting for replies here.

 

Can you turn the 2m power down? I hit repeaters 30 miles away with 10W. I can't imagine 75W.

There are lip mounts and Jeep under hood mounts. The hood mount is just an example. It says for 1997 and newer but I don't have any experience with it. You get the idea though.

walcottcb.com/diamond-k412c-trunk-lip-mount-p-1831.html

walcottcb.com/firestik-mkj4r-jeep-wrangler-hoodfender-channel-antenna-mou-p-602.html?cPath=28_353_430

 

Yes......did not "seem to" is the point. Until you've tried it both ways, far apart and close together, AND had the test equipment to test the radiation pattern, then how would you know? "Close" is a relative term anyway. If they are "too close" they WILL react to each other....it's a matter of physics. But weather it is doable or not, all a person can do is try it. All antennas, and ALL applications will be different.