Fitting UHF antenna NM

[buckster]

Does anyone have any thoughts on where to fit an antenna for a UHF CB on a NM?

The shop i bought the CB from stated the best position for a 6db GI antenna is on the roof. I was going to fit it to the bull bar but they said I would get far better reception with it mounted on the roof. They tech screw it to the roof gutter and hide the cable the under the windscreen rubber, to come into the cab through the firewall. I have looked at the windscreen and cant see how you could get the coax under it?

[Rusty]

Buckster
Our NM had the aerial fitted to the nudge bar and reception was great. Must admit though that i don't recall what power rating it had. Best we ever recorded was over 30km around Wolf Creek Crater last year

[AdrianLR]

On the NP, I've got mine mounted on a Z bracket between the bonnet and the guard on the driver's side. Works well in front of and behind the vehicle. Also a useful guide to clearance - the tip is a few inches higher than the roof bars - so for getting into carparks if the antenna does touch then neither will the bars!. "Tec srewws into gutters" sounds a bit crude.

Adrian

[gp339gm339]

The centre of the roof of any vehicle is the best location for an antenna.

I would be concerned about the TEC screws as they will cause rust eventually.

Also being on the gutter if you hit anything as the 6 db antennas are usually tall you could cause damage to the gutter.

I prefer the bull bar position as its lower and less prone to be broken from trees on the side of the track. Although I have replaced heaps of antennas on bull bars that have been snapped off. You do have some reduction of coverage behind the vehicle.

I use a 3 db RFI GPI antenna that has a flexable whip (its nearly impossible to brake off. The other consideration is that the higher the gain the flatter is the radiation donnut, its great for where you are driving in the desert. But in the hills I have seen guys with high gain antennas haveing no coverage from the bottom to the top of a hill.

Harold

[Wal]

I did quite a bit of research on this before I fitted my GME TX3400 last year to my new Paj. Yes, mounting your aerial in the middle of your roof will give you the best coverage but it's not very practical. Side gutter mounting is the next best but also has a number of logistical problems as already mentioned. The next best place is the LHS upper bullbar mount. Not so far left that it gets caught up in foliage but far enough to improve signal reception from behind your vehicle. This is what I chose as all the other options are worse.

I easily managed to communicate over sand dunes in the Simpson using the 6dB whip to monitor oncoming traffic. Reception coming from behind was nowhere near as good but that wasn't a concern as they'd see me before they hit me.

My best range? Traveling out of Kings Canyon I had to go 80 kmh to get out of the NP to collect firewood yet I could still hear the resort staff communicating via their handhelds. Yes, direct line of sight but still impressive.

My aerial is a GME AE409L. It has a replacement whip which is rated for 9dB but I stick with the 6dB as it does the job.

[buckster]

Thanks to all those that have replied. I think i will now mount mine on the bull bar.

cheers

[Aussie]

Hi,

I also have my antenna mounted on a Z bracket. Passenger side upper corner of the bonnet. No need to drill any holds in the care, just remove the bolt holding the panel on, drill out the Z bracket to fit bolt though. Cut the rubber seal along the panel so you can slip the bracket between it and the rubber.

Here's some pics for you to look at





Had to put this one in for fun but you can see the base of the antenna.



Cheers,
Ben.

[buckster]

thanks, the track looks quite challenging. The bracket looks good too....

[Adza]

Yes you will get best reception in the middle of the roof.

But in practical terms, the general user won't really be able to tell the difference. Not many people put them on the roof because (a) you have to drill a hole and (b) it adds to the height of the vehicle.

Just put it next to the bonnet or on the bullbar. It will be fine.