Thread: Antennas - please explain

In tassie a 4 or 6db is the go, better for hilly terrain. 6db is a good around, 9db for big flat country. Yours will do the job, most common is 6db. Buy a little stailess bracket that mounts on the mud guard and fits out the slot between the bonnet and guard
cheer
blaze

There's been a bit of discussion in the past about antennas so you could try a search.

In brief thought (IMHO) the best all round antenna for your D1 would be the elevated feed/ground plane indepedent style. These have the advantage that they do not need to be mounted on a ground "plane" or flat piece of metal to work properly. Also they come pre tuned so no worries there. You'll normally get a couple of whips ( the top bit ) with them - a gained one and a shorter unity gain one.


Here's a link so you can see what they look like : ( there's three or four different makes available )




http://www.polarelectronicindustries.com/model.php'model_id=466

You can get them with or without the spring - I'd recommend one with the spring. Mount it as high as you can without it becoming a nuisance. Mine's mounted on my roof rails with an L bracket - but that doesn't suit everyone. Whatever you do it, the upright part should be physically separated from any metal on your car and from any other antennas by at least half a metre.

Oh BTW the antenna whip you have there sounds like what is known as a "5/8th" antenna. It has a bit of gain but does need to be mounted on a ground plane. ( or an idependent ground plane base as above ).

Give Icefyre a pm, he has a good setup mounted off his spare wheel carrier. An extendable pole allows him to raise or lower it as terrain dictates.

Definitely go with an independent ground plane type antenna, they are worth the extra $$$

Also, there's nothing at all wrong with the aerial that you have got.

I used to run those cheap wire ones on my work vehicles, usually mounted either on a gutter mount bracket, or on a roof rack, and often found them to give better performance than some of the more expensive units.

If you are in a convoy strung out in the flat desert, a long 1metre or so antenna of say 6Db gain is helpful, as it sends out a long narrow( from top to bottom eg <) radiation of energy.

In hills this is not so good as sometimes the other cars can be above or below the radiation, so you can hear others but they cannot hear you.

A shorter lower Db antenna (eg 4Db) sends out a wide beam and can be heard by people over hills etc better than the high Db gain, but has a shorter range.
In most convoy situations the low Db antenna is quite adequate.

In any case you can relay through someone half way along the convoy.
Regards Philip A

Originally Posted by PhilipA

If you are in a convoy strung out in the flat desert, a long 1metre or so antenna of say 6Db gain is helpful, as it sends out a long narrow( from top to bottom eg <) radiation of energy.

In hills this is not so good as sometimes the other cars can be above or below the radiation, so you can hear others but they cannot hear you.

A shorter lower Db antenna (eg 4Db) sends out a wide beam and can be heard by people over hills etc better than the high Db gain, but has a shorter range.
In most convoy situations the low Db antenna is quite adequate.

In any case you can relay through someone half way along the convoy.
Regards Philip A

That's where the GME interchangable aerials are good. Stubby for round town/hilly stuff, bigger mast type for the desert.

Plus the service guys can unscrew it easily when your car goes up on the hoist.

Regards
Max P