UHF radio - unit and antenna mounting locations

Thanks for the advice Rally. The US charger isn't really an issue as I already have interchangeable charging gear from overseas travel but I don't want anything that isn't approved for use here. The gps locator seemed like a good safety feature if I ever needed to give my location to emergency services.

I found a GME unit (GME TX3100 PLUG N PLAY UHF 5W 80 CHANNEL UHF RADIO ANTENNA PACK PORTABLE) that is portable though I think this might mean it can be moved from one vehicle to another rather than being used as a hand-held. Would this do the job seeing I'm not planning on any outback travel, just day/weekend trips around Brisbane?
 
What's the issue with plug and play?
 
Don’t know about plug and play. A normal 3100 should be fine. The aerial should be ground independent and the top of the aerial needs to be the highest point on the car.
 
What do you mean by "ground independent"?
 
A ground independent aerial means that it doesn’t matter where on the car you mount the it, the signal will radiate out pretty much equally in all directions. This is assuming the aerial is tall enough to clear all obstacles such as the roof and anything on the roof. A ground dependant aerial is different. Say you mount a ground dependent aerial on the centre of the bull bar. The signal will mostly radiate to the back of the car, so those behind you will hear you further away, but those the same distance in front won’t hear you.

When I was running HF radios, I had twin 9 foot whip aerials, one mounted on the bull bar, the other on the tow bar. If I was at the back of the group, I would use a switch and use the rear aerial, or if I was in the front I would switch to the front aerial. The difference was significant if you were on the wrong aerial. If you wanted ideal performance from a single ground dependent aerial, you would need to mount it in the centre of the roof.

Ground independent aerials are so common it’s best to go with them for most people. These days they tend to be the default option, but you just need to make sure. And with aerials of either type, height rules. They need to clear all obstacles.

The other point to keep in mind with UHF is irrespective of aerial or it’s height, any signal at this frequency is pretty much line of sight. Whereas with HF and VHF to a lesser extent where the signal can deviate around hills and the curvature of the earth, UHF won’t. So if there is a hill between you and whoever you talk to, they probably won’t hear you. Which is why UHF has range limitations due to the curvature of the earth, and why it performs poorly in hilly terrain. Signal quality, when you get it, is significantly better. Which is why UHF is so popular and hardly anyone, at least in Australia, uses HF anymore. As a result, all the newer technology and features are found in UHF.

HF has it’s advantages but for most people they are not enough to outweigh getting UHF.
 
Not withstanding the above, with uhf aerials some are better for hilly terrain than others. At one end you can have an aerial which is best for hilly terrain but with less overall range, and at the other end you have an aerial which is best for optimum range but performs poorest in hilly terrain. Or you can get one in the middle.
 
I've got a GME 3100 in the Triton and a GME 6150 hand held in the Foz, both are 5W. I have an external antenna, external speaker, which is not really necessary, and separate mic set up for the hand held so it acts just like an in-car unit. Both work very well indeed. Using a CB mic when traveling is no big issue at all. When I'm out and about in the Triton the 6150 comes along as well.
 
Beachworm said:
The gps locator seemed like a good safety feature if I ever needed to give my location to emergency services.
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Get yourself a PLB in addition to a radio. I hope I never need to use mine, but I don't go bush without it. plus, it goes via satellite, so you can be found if nobody can hear you.
Plus, it will work even if your car is busted up to the point where the two-way no longer works.

Rally said:
Not withstanding the above, with uhf aerials some are better for hilly terrain than others. At one end you can have an aerial which is best for hilly terrain but with less overall range, and at the other end you have an aerial which is best for optimum range but performs poorest in hilly terrain. Or you can get one in the middle.
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I'm surprised no-ones developed a combination aerial yet. from my understanding, a lot of it comes down to length. Wouldn't it be possible to combine the two (say have the 2.1db towards the top of the arial, and a switch to change between the two)? Not that I know anything about antennas.
 
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Kevin said:
I've got a GME 3100 in the Triton and a GME 6150 hand held in the Foz, both are 5W. I have an external antenna, external speaker, which is not really necessary, and separate mic set up for the hand held so it acts just like an in-car unit. Both work very well indeed. Using a CB mic when traveling is no big issue at all. When I'm out and about in the Triton the 6150 comes along as well.
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So - if I'm understanding this correctly, and there's some doubt about that, it doesn't make much difference whether the unit is in-car or hand held as far as performance goes. It all depends on the antenna. So a 5W hand-held with a roof mounted antenna would do the job. (not sure how the antenna would connect to the hand-held?????
 
Correct. Assuming both are 5w
 
Beachworm said:
So - if I'm understanding this correctly, and there's some doubt about that, it doesn't make much difference whether the unit is in-car or hand held as far as performance goes. It all depends on the antenna. So a 5W hand-held with a roof mounted antenna would do the job. (not sure how the antenna would connect to the hand-held?????
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Some hand helds have an antenna input. couldn't tell you which ones though.
 
I've sent a message to GME to see if they have one that can connect to an external antenna.
 
Beachworm said:
I've sent a message to GME to see if they have one that can connect to an external antenna.
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Hopefully their response and the information I supplied above will allow you to find the set up you need
 
Ben Up North said:
I looked at getting that but the on-going costs seemed a bit extreme for the ability to send messages (which is pretty much the only real advantage from what I can tell).

[MENTION=114]Kevin[/MENTION] should this be a different thread?
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Probably - I'll sort it later
 
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