Thread: One for all the experts

GME4700 series and whack it on the front bar

you can get a nice benelec independant ground high mount that comes with 3db and 6db heads if my memory serves me correctly. nice units in my experience...

I think that incisor meant "ground independent".

For your information, the higher the dB rating of an aerial, the more focussed is the signal, meaning less suitability in hilly terrain. Therefore, I suggest that a 3 or 4dB ground independent aerial would be better for your needs.

Best Wishes,
Peter

Interms of power the difference between 3 db and 6 db is 50% or 200% depending on which you use for a reference either way it is 2:1. All that the higher gain antennas are doing is pushing/receiving less power to/from higher angles eg, not pushing power out directly overhead. Unless you have mountains that are at an angle higher than 45 degrees above the horizon you will not suffer from the reduced power sent/received from overhead. If anything you will be able to push further into the valleys as you either bounce or refract of the hill walls of the valleys/canyons. As long as you don't go 10 db and higher I don't belive it will make a difference between a 3 and 6 db whether you are in mountains or out on the flat the 6 db should out perform the 3 db in both cases. But then again what is 3db in amongst friends (1/2 power)

Actually the gain on an antenna is based around the shape of the radiation lobes. Imagine a lobe being a big doughnut wrapped around the antenna, increasing the gain flattens the doughnut out. It makes it more powerful/sensitive in the horizontal direction at the expense of the vertical direction. Since the UHF band more line-of-sight and less bending around objects, in hilly country the extra horizontal range isn't going to give you any benefit. More to the point if you are travelling along a flat road and some one is at the top of the hill above you, the higher gain antenna may actually reduce the signal.

mate

3db, east cape there are plenty of repeaters as well as around taupo and tamranui etc. taupo to napier in the hills is dead that’s why the cops are still allowed to follow ( read chase). piction to nelson after havlock is dead as is hast. all of the west cost is patchy. but any repeters are high so just stick with the 3 db on as longer whip as you can afford

Most of the above comments are valid - some unique ways of describing RF propagation theory there.

A ground independent antenna ( the one with the shiny chrome tube at the bottom ) mounted as high as you can get it is the way to go. If you can mount it up on a roof bar or something, so much the better. Otherwise on the bullbar. Far back near the A pillar not so good. Use a 1/4 wave whip ( the short one about 6" long.) - you'll be sweet as bro.

Originally Posted by waynep

Most of the above comments are valid - some unique ways of describing RF propagation theory there.

A ground independent antenna ( the one with the shiny chrome tube at the bottom ) mounted as high as you can get it is the way to go. If you can mount it up on a roof bar or something, so much the better. Otherwise on the bullbar. Far back near the A pillar not so good. Use a 1/4 wave whip ( the short one about 6" long.) - you'll be sweet as bro.

LOL no therory just what works, i used one of ths shiny ones mounted on a small fiberglass boat mast glued to the bull bar. and i know about the napier road, coz the pigs blower said so when he was reading the charges eh and all the bros cracked up when he got to the bit about blowing up the 253 V8 and the B$W mizi that fell off the road