CB mounting

[BSH]

This is really more radio tech than Jeep tech, but I'm someone here is knowledgeable. If I mount my antenna toward the front of the roof of my XJ, will the antenna derive good ground plane from the hood?

I know the "ideal" location is the middle of the roof, but naturally I want to also make use of that nice rack up there for stowing gear. So if I mount the antenna more towards the front, will I still have good signal, better than those bumper mounts or taillight mounts?

 

[PAXJ]

By rack do you mean one other than the factory rack? If so just mount it to that. The ground plane really refers to what the antenna is mounted to, not where. Thats why the center is ideal, then the ground plane becomes the whole roof all the way around.

 

[Captain Ron]

Ground plane is technically the other "half" of your antenna system. While not exactly a vertical "dipole", a vertical requires a "counterpoise" to be effective. Where it is, is just as important as what it is.

By far and away, the best match for a mag mount is the center of the roof, without any rack, on a XJ. As you move it out from the center, the reactance of the ground plane portion of your antenna will change, and not for the better.

A mag mount will perform reasonably well though with a stock rack, mounted forward of the rack. Your signal will be directional towards the front.

With an aftermarket rack, it gets tougher to get a match. Quite a few factors come into play. Grounding the rack, rack affecting the "Q" of base loaded coils, location, and so on.

--ron

 

[casm]

What I did was to keep a permanently-wired magmount under the driver's seat, then stick it on the roof (as close to dead-centre as possible) when I needed it. The antenna was pre-tuned and stashed under the back seat squab, and screwed into the base as necessary. It worked great.

One thing that I find mildly annoying in CB threads (and this isn't a personal attack, just a general observation) : people seem to be obsessed with getting as close to a perfect SWR as possible. For trail use, as long as you can get down to around 1.2 or so on whatever channel you normally use you'll be fine.

 

[creeperjeep]

For trail use, as long as you can get down to around 1.2 or so on whatever channel you normally use you'll be fine.

sh.it if I could get that normally Id give ya $100