Ground Independent Antennas Question

Your installer is not entirely correct. The radiation pattern from a GI antenna isn't affected by the presence or absence of a ground, BUT metal will affect the radiation pattern. e.g. if you have it mounted on the bullbar, expect it not to work as well behind you as in front. The door pillars, doors, roof, cargo barrier, rear doors, canopy etc. will all affect the signal.
Up high and clear of obstructions is the best place for any antenna, GI or not.

G'day Michael

Your right of course. The top of mine pokes just a little above the vehicle roof so general allround send/recieve is okay. It does work better to the front though.

Regards

Paul

The presence of a large metal surface to the rear (front mount), will cause the signal to lobe to the rear ie. stronger. But because a lot of the signal is obstructed by the roof line, the end result is a weaker signal to the rear. There is no substitute to having the antenna as close as possible in length to the wave length being transmitted, and being located in the middle of an unobstructed ground plane.

Bazza,

If you bought the "kit", not just the antenna, it will come with a base and cable that will need to be mounted through a hole. I had to ream out the 12mm hole in my bullbar to suit (probably closer to 15 mm). If you intend to mount this in your roof, be prepared to make a large hole in your roof and pull all the lining off to hide the cable. I think you will still end up with an unsightly lump in your roof lining (unless you have a console to hide it). The mounting kit is designed for bullbar mount and only the top thread protrudes above the hole. I would recommend bullbar mounting it if you have one. The 9db assembly is quite long and would make height clearance a real problem in urban areas.