Jeep Roof Rack antenna mount?

[Riptyd]

Hello all,

Complete new guy here and hoping to gain some quick knowledge. I have a 2008 Jeep wrangler 4dr. The top is removeable and spends about 40% of the time topless, as you can see in the attached link I have a complete roof rack. It is all steel and bolted to the body of the jeep. I would like to use a mirror bracket to attach my antenna to the rack giving me clear line of sight in att directions and at the highest point on the jeep. I have a Wouxum KG-UV3D handheld but will probably be adding a proper mobile unit in the future. Does anybody see any problems or have any tips before I purchase an antenna and bracket? I am still confused to the groud/ground plane difference and am still trying to learn. Oh and one more thing I will be predominately in the 2m range when using this set up, but would still like to be dual band if possible.

Thanks for all constructive advise you guys/gals may have.

73's
KJ6TJR (Rick) Out

[tjboomer]

Hey Rick,

Recieved an email from a fellow Operator about your question. I'm a jeep enthusiast as well and he thought I might be able to help with your questions. So here goes:

Ground vs Ground Plane - A ground plane allows an object to act as a reflector or director (when transmitting or receiving) for an antenna like the earth or the ocean. In this case the object/vehicle (Jeep) can also act as a reflector or director for the antenna. If the antenna is placed at the rear of the vehicle then most of the reflection and direction is toward the front of the vehicle and vice versa if the antenna is mounted on the front of the vehicle. This is why most people will try to install an antenna in the center of the vehicle (on top of the vehicle). It provides the best front to rear ratio reflection when receiving and direction when transmitting and also places the antenna as high as possible.

In order to have a good ground plane one must make sure that the antenna and radio are well grounded for maximum ground plane and antenna SWR. Most problems that people have when the seem to get weak reception or transmission are due to bad grounding. So you will always hear "ground, ground, ground".

As far as the Jeep goes, just make sure the rack is well grounded to the Jeep and the antenna is well grounded to the rack. Placement is as you desire with the above in mind. Currently I'm running dual band (VHF/UHF) antenna located at the back of the vehicle (making it forward directional). It is mounted on the tailgate hinge for garage door clearance since I garage my jeep every day. I have no problems communicating with repeaters or symplex.

A web site you may want to check out is Stu Olsons site ( http://www.stu-offroad.com/ ) It is a web site for Jeepers like you and me and contains all kinds of info. Stu is also a ham radio operator and there is a section just for jeeps and ham radios that could possibly answer any questions you might have. Stu is a great guy to chat with and is always very helpful. I also have a few write-ups hosted on his web site so check it out.

This was all said with symplicity in mind. I'm sure others out there will chime in as well. Hope this was helpful and if you have any further questions please feel free to PM me.

From one Ham Radio Jeeper to another here is a big Jeep Wave to ya. 73 Good luck
Dave
AKA TJBoomer
AF5IB

[5B4AJB]

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