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steveG
9th December 2008, 08:01 PM
Hi,

I've picked up my first UHF (an old Uniden UH100) for my D1.
I dont have a bullbar, so after a search here I'm tossing up between mounting the antenna on a bracket in front of the bonnet, or on a bracket on one of the front guards.
Any comments on pros/cons of those locations.

Can anyone suggest an inexpensive antenna that will be OK for convoy comms? I had a look at Dick Smith at lunchtime today and a 4.5db ground independent antenna was around $100. I'm hoping there is a cheaper solution.

Do I need to get one of the heavy spring mounts for the antenna, or is that only required for the bigger antennas?

SteveG

waynep
9th December 2008, 08:15 PM
$100 sounds about right for an elevated feed antenna ( the one with the shiny tube at the bottom.)

You can go with a standard base and a 1/4 wave or 5/8 whip that will cost you around $30, but these should really be mounted on a ground plane to make them work properly. ( a ground plane is a horizontal sheet metal or grid at least half metre square ) The centre of your roof is technically the best position on your vehicle to mount an antenna, ( height and good ground plane ) but it's not often used for obvious reasons. The elevated feed antenna has its own ground plane "built in" so can be mounted anywhere.

A spring base is a good idea as it wil deflect if it strikes branches etc.

Do you have roof bars ? The trick with a UHF antenna is to get it as high as possible. This solution is not for everyone but suits me very well. I mounted my elevated feed antenna on the roof bars with a couple of u clamps and a right angle bracket, and ran the cable down the a pillar gutter. It has a spring base so I just tie it down against the roof bar with a cable tie when I want to garage the car. I only use the UHF when offroading so it stays tied down for much of it's life.

steveG
9th December 2008, 09:03 PM
Thanks Wayne - that's a mounting option I hadn't come across in my searching.
I hadn't noticed that there is actually a gutter in that A pillar molding. Looks like a great place to run an antenna cable. I'll have a better look in the daylight tomorrow.

From the base of the gutter did you just run the cable down into the engine bay and through the main firewall grommet?

waynep
9th December 2008, 09:10 PM
Mine just runs down through the door seal but through the grommet would be better.

to keep it in the gutter put a couple of dollops of silicone over it.

Treads
9th December 2008, 09:36 PM
If Icefyre (http://www.aulro.com/afvb/members/icefyre.html) is around he might post a pick of his setup. It's mounted to the spare wheel carrier on the back door. He's used an elevated feed on an extendable tent pole so it can be lowered when driving in wooded areas.

It's also a great spot to mount a rear worklight as well :)

steveG
11th December 2008, 10:07 PM
Mine just runs down through the door seal but through the grommet would be better.

to keep it in the gutter put a couple of dollops of silicone over it.

I was in a hurry tonight to get it working before the weekend, so I ended up doing the same thing and running it through the door seal.
I bought a Benelec 3+6db elevated antenna kit from Dick Smiths, along with a mirror mount plate and mounted it on the roof bar.

Got it all wired up and working tonight (albeit with the radio not actually mounted anywhere and just sitting on the passenger seat).
With the 3db antenna fitted it seemed to get pretty clear reception and I listened to a chat between 2 truckies for about 10 mins before they dropped out of range.
Will see how it goes this weekend on the Wombat trip.

SteveG