Thread: UHF Radio Advice Please

Re the aerial, a lower gain might be better for the desert. If you run GME, its easy to have a couple & swap between hi & low gain depending on the conditions. More info on their site

http://www.gme.net.au/public/pdf/brochures/land_b.pdf

And you can unscrew it if you're really worried about corrugations - just don't use the radio.

And ground plane independent are easier to install too.

Regards
Max P

Thanks for that.

Are you suggesting lower gain to get over and into the next trough(s) of the dunes?

I was assuming that a higher gain would be better for distance across the dunes and assumed that the low gain aeriels would be used for more mountainous areas - at least that was my reading of pg12 of the GME brochure thought Id be the first to admit Im sort of guessing!

As there are a few vehciles going on the trip I cant unscrew it on the corrugated bits as I cant then communicate, and 90% of the trip will be corrugated anyway!

It is a valid point though about unscrewing to change antenna. Do people actually do this? Does it make that much difference? I know many people have 2 aerials but do they both get used?

Thx
Jon

The GME TX3340 would be the equivalent of the iCom IC-440. They are user upgradable to the 80 channels (just need to add a code when the licence issues are resolved in the next month or so). Most people I have spoken to report that they have found GME radios more reliable than Uniden.

As for antenna gain, unless your group are strung out over a long way, you will probably achieve little from a high gain antenna. I would expect you will typically travel in a relatively close convoy not more than a few hundred meters apart. Will you really need to communicate with some one 10-20+ km away. Also small gain antennas tend to be smaller and are probably less prone to fatigue from corrugations. I suspect if your aerial is going to breakdown from the corrugations, you have far more important issues with the rest of the vehicle to worry about.

Hi Jon,

Before I bought my IC-440 for the Defender I had a basic Uniden unit in the Disco and it worked without a problem for the 10 years that I owned it. It's a bit like the Engel versus Waeco debate....some good experiences some not so good.

I have a RFI antenna with two aerials..a 6 dBa and a short 3 dBa. The latter I use in hilly country as the signal is better distributed. The 6 dBa signal shape is like a flattened donut and has a longer range in flat country and the 3 dBa is more spherical and has a shorter range in the horizontal plane.

Your response from Prestige suggests that the IC 440 cannot be reprogrammed unlke the 400.

Originally Posted by KarlB

The GME TX3340 would be the equivalent of the iCom IC-440. They are user upgradable to the 80 channels (just need to add a code when the licence issues are resolved in the next month or so). Most people I have spoken to report that they have found GME radios more reliable than Uniden.

As for antenna gain, unless your group are strung out over a long way, you will probably achieve little from a high gain antenna. I would expect you will typically travel in a relatively close convoy not more than a few hundred meters apart. Will you really need to communicate with some one 10-20+ km away. Also small gain antennas tend to be smaller and are probably less prone to fatigue from corrugations. I suspect if your aerial is going to breakdown from the corrugations, you have far more important issues with the rest of the vehicle to worry about.

The GME unit does not have the speaker in the handset, thats why I discounted that model some while back. Interesting point about reliability though.

As for the "convoy", you are of course correct, however i dont envisage the vehicles being close together at all. I want to be well out of the way of other peoples dust and so could expect the vehicles to be a km or two appart at any time, then coming together again at various meet points / campsites, or when someone gets stuck

Originally Posted by one_iota

Hi Jon,

Before I bought my IC-440 for the Defender I had a basic Uniden unit in the Disco and it worked without a problem for the 10 years that I owned it. It's a bit like the Engel versus Waeco debate....some good experiences some not so good.

I have a RFI antenna with two aerials..a 6 dBa and a short 3 dBa. The latter I use in hilly country as the signal is better distributed. The 6 dBa signal shape is like a flattened donut and has a longer range in flat country and the 3 dBa is more spherical and has a shorter range in the horizontal plane.

Your response from Prestige suggests that the IC 440 cannot be reprogrammed unlke the 400.

Thanks Mahn,
The IC-440 can not be re-programmed. You need the 400 for that.

Do you know what your RFI model numbers are? Ideally Id like something I can unscrew and swap. The model suggested by presteige doesnt give me that ability, but does give (apparently) a much stronger, reliable unit.

Jon,

This is what I have:

Prestigecom.net.au 3 & 6.5db Ground Independant 4WD Antenna Package - $119.00

Speaker in the microphone can be a good thing but benefits are often limited unless you have the microphone in your hand and near your face. Better, I think, is either to have an aux speaker near you ear (eg just behind your right ear on the roof) or the CB out-put to the vehicle's radio speakers. This latter option would be particularly good for a Puma which is quieter in the cabin than in other Defenders.