CB antenna: Hard mount vs. magnetic?

[mbeach]

This is one of my professional areas of expertise, so here goes:

1.) We do not use Wilson products. They have failed under some (very) extreme conditions, and their support was minimal after the failure. We use Maxrad antennas exclusively (VHF, UHF and cellular). Quality and durability are excellent, and if any failures occur, they stand behind their products 100%. They were recently purchased by PCTel, and their service has continued to be excellent. They make a 49" loaded whip (3 dB gain) for the 27-31MHz CB band that is outstanding. I can dig up the model number tomorrow (we order these things by the dozen, for less than $30 a piece).

2.) We use NMO style mounts. These require a 3/4" hole to be drilled in the roof. A clean hole saw, or sharp unibit will handle this. We use Maxrad "Motorola Style" mounts, these are two piece, low profile mounts that use an O-ring seal to keep out moisture. The mounts are purchased with 17' of RG-58 cable attached. They can be preterminated with the connector of your choosing (most CBs take a PL-259).
A metal screw-on cap can be installed over the antenna mount whenever the antenna is removed.

3.) If you choose to mount the antenna anywhere other than the very dead center of the roof, performance will be compromised. The antenna (all antennas, despite manufacturers' claims) require a ground plane. The more metal you have in every direction, the better the wave propogation.

4.) A mag mount antenna, placed in the center of the roof will outperform any permanent mount that is placed poorly. Ensure that you don't kink or crush the coax cable in a door, this will change the impedance of the cable and degrade performance.

I hope that this information helps any decision that you make -quality parts and installation are a lot cheaper than a radio failure or lost comms due to a broken antenna.

I should mention that our installations handle the beating of the Trans-Alaska Pipeline's "haul road" with ease, even at -60*F. No leaks, no loosening, no failures after installation and testing. In rolling terrain, our CBs (Uniden 510 Pro Xls -cheapies) routinely reach out 12 miles or more.

[WyldWeasel]

Thanks to everybody who responded to this post so far. This is all good stuff to know, as not only will I be using my truck out at Moab but I plan on using it regularly at a ranch where cellphone coverage is nonexistant and having a CB for convenience and to communicate in times of emergency would be a great thing. If I do mount the antenna on the roof, then how will the addition of a rack/basket such as the Load Warrior compromise the antenna?

[mbeach]

If the basket is steel, it'll increase the ground plane. This would be good.

[Jolly Roger VX'er]

I liked his (Tonka) setup alot:

http://www.vehicross.info/gallery/sh...php?photo=1817

[dynofan]

Just a thought....... I've used a hide-away antenna that plugs into the radio antenna from JC Whitney. It is tuneable; granted, not as powerful as a whip...... but doesn't advertise the cb when parking places I don't trust!

[mdwyer]

This post is ancient, but I just came across it and wanted to add some of my notes to it.

I installed a permanent mounted antenna in the roof of my VX. I'm using 2m/70cm ham antennas instead of 11m CB antennas, so the sizes are different. Still, most of the idea still holds. For best results, use quality parts and mount the antenna in the center of a mass of metal with a clear 'view' to the horizon.

Someone mentioned an NMO mount. This is a great idea, because it also allows you to swap out antennas when you want. So, you could have a coil-loaded short antenna for day-to-day driving, and swap it for a monster whip antenna when you're playing in the hills.

I'm not sure how that will work for CB antennas, though. They are typically longer, so roof-mount might not be a possibility at all for you. You'll probably have to mount it lower, and your performace will suffer somewhat because of it. You might need to look into some sort of flexible mounting to limit damage if you hit something. (And a tennis ball. ) My antenna is about the same height as the stock radio antenna, so it is relatively safe. I've got a better (longer!) antenna, but I couldn't park in my own garage if I left it installed.

Make sure you remove some paint around the edgest of the hole you drill, to allow your antenna to ground to the roof well.

Putting your antenna near the stock radio antenna would be nice, but keep in mind the ridges of the roof. They are too narrow to hold an NMO. This makes most of the roof totally off-limits. Instead, I put mine just in front of where the center ridge ends -- the rear-center of the flat part of the roof. This lines up just forward of the dome light, which makes it really easy to run cables. They follow the dome light cables towards the passenger door and down the A-pillar.

There are also trunk-lip antennas (which you could also put on your hood) or antennas that go on the luggage rack. The license plate frame isn't a bad idea, either. Check out the ham radio field for other ideas -- amateur radio "10-meter" antennas are really close to CB antennas, so the technology is comparable. If you've got Tone's hitch installed, the receiver hitch antenna mount might fit your needs.

I used an NMO mount from Larsen. Keep in mind that the difference between cell phones (at 900-1800MHz) and CB (at 27MHz) is large enough that the NMO connectors aren't necessarily interchangable. That is, the mount for a cell antenna won't perform as well as a mount for a CB antenna.

Larsen also makes antennas, but I went with Diamond Antenna because they had one that was not much longer than the stock radio antenna. It looked nicer. If I want a better-performing antenna (which is longer and uglier), I can just unscrew one and screw on the other.

Spend money on a good antenna even if you aren't ready to drill holes in your VX. Get a mag-mount with an NMO on it, and it will work adequately until you get up the guts to install a permanent NMO mount. It will also give you an option if you want to use your radio in a different car.

I did my shopping at Ham Radio Outlet, but you might also be able to pick up something at Amateur Electronic Supply. Ham operators are probably going to look down upon you for using a lowly CB, but they know their products, well. For example, this site has a LOT to say about the relative quality of various antenna mounts.