UHF radio in a D-Max

G'day William.
Just my experience with UHF over quite a number of years. Having the aerial up the highest you can get to on your vehicle is the best position. I use the option of two aerials ( not close together) for two radios. One for highway monitoring and the other for local use, calling caravan drivers not on 40. Aerial on bullbar is not the optimal position by a long chalk. Twice for life saving reasons, accidents encountered, the radio has performed well , with 70km transmit and receive quite common in both cases. Always disputed of course.
I also have two GME hand helds, with a 280mm approx, flex aerial which has been used and From Kyabram Vic to Bendigo Vic repeater, I can talk to the repeater. With a recent addition of a GME TX6150, it has a short aerial and is handy for contacting the vehicle from a distance. Used with an aerial adapter to feed a magnetic base aerial on roof of any vehicle is also convenient without an installation of gear. While wattage is important, the actual setup, ie aerial combination and position and type, which works, is equally important. Conditions and terrain play a role too in performance. There is a recent thread/posts discussing similar concepts.

Hi William

Hope you are enjoying your new D Max, they are a great vehicle and you should be very happy with it.

I was in the same boat as you, as I have not fitted a bull bar, so I went for a good quality 5w hand held unit and went with the Icom.

I was going to go with GME, but when I spoke to a specialist store in Adelaide they recommended the Japanese made Icom 5w, they said they were very reliable unit compared to the cheaper Chinese made GME which were prone to nagging issues.

GME do make a 5w Australian made handheld at almost double the price of the Icom, but they were honest enough to say it was not worth the extra dollars.

By going the handheld, you don’t have to worry about concealing the main unit under the consul and positioning the microphone and antenna.

Happy and Safe Motoring.

I have a hand held 5W Icom unit in the back of the OKA.. It is fitted with a power supply and external antennae which makes its performance identical to an installed unit. BUT I can take it out, fit the original antennae and go for a walk with it.
The antennae position is the most important feature determining performance.
Cheers,
Peter
OKA196 motorhome

We have a D-Max with a UHF fitted in the pocket under the steering wheel. We have another D-Max that has a UHF fitted under the console, in front of the shifter. We also have two 5w Uniden hand held we use for
communication with people outside of the utes. ie when winching or bushwalking.

Fitted UHF is available always as long as the vehicles battery is charged. Better range.

Handheld. More flexible but you have to keep charging them

Hi William B,

The choice between fixed or handheld really comes down to your personal choice. I have both a fixed 5 watt in car unit and a pair of 2 watt handheld units. The fixed in car unit is paired with a 6 dBi antenna. The handheld units we use for comms when manoeuvring the car and caravan into tight spaces, or when out bush walking. Of course as they are only 2 watt, their range is limited.

The most important thing with a UHF radio when travelling is to have it switched on and monitoring the highway channels (40 for the majority of highways, or 29 on the Pacific Motorway). These are the channels that the majority of trucks, and Pilot vehicles use. Whilst many caravaners use channel 18, you will not hear important information regarding oversize loads coming towards you from either direction, or potential hazard information. I have found that the majority of foul language or the abusive idiots who just like to try and have an argument with anyone are usually around the major cities. Once out on the open highway, it tends to disappear.

The next important thing to remember with any UHF Radio is the choice of antenna and more importantly it’s position relative to the centre line of the vehicle. Even the best UHF Radio will not perform as well as it could if you have a poor quality antenna.

Ideally the best position for the antenna is the centre of the vehicle at its highest point. Not always possible or practical especially with roof racks, or low hanging obstacles. You can get adjustable antenna bases that can be attached to the side of a roof rack, and can be adjusted so that they lay flat, or on an angle when negotiating low lying obstacles such as underground carparks etc. However these can be inconvenient as you have to get out and make the adjustment manually. Of course you lose transmission range by having it in the lowered position.

The next best position, in my opinion, would be the centre of the Bull bar. I have chosen to have mine mounted to the passenger side of the Bull bar utilising an existing mounting bracket on the Bull bar. Not the most ideal position, but I have a light bar fitted to the centre of the Bull bar, so it was the next best position. If you do not have a Bull bar, you can get a “Z” bracket to attach it to the top of the mudguard where the bonnet comes down. Not ideal, but it is an option.

Macca.

I have the new BT50 and went with the 5w GME handheld with the in car adapter kit. Works just fine. UHF is more for convenience these days rather than worrying about ultimate performance.

When I bought the GX 200 series new in 2018 I swore I would never have another bulbar because I don't drive at night much anymore so installed the CB with the aerial on a Z mount. works really well, Did fit a bull bar in April 2023 as we are travelling the East coast and there are many wild animals over here !
The aerial is still on the Z mount; the executive director of housekeeping likes the better vision.

MU-X instead of DMAX but close enough. I use a GME XRS-370 with an on-glass AE5002 antenna. It is mounted high up on the front windscreen out of the way. Coax is hidden behind the pillar cover and the excess cable shortened and re-terminated. Works very well. The GME CP50 5W handhelds are just used out of the vehicle.

I use UHFs but they are very limited and get used as such. Don't ever consider them as a reliable form of emergency communication.
Don't waste money on big heavy "look at me" antennas, a 150mm on a elevated feed ground independant base with no spring will do all you will want and not destroy itself from excessive movement like the heavy ones. 12 years in mining and rail construction keeping UHFs working as reliably as possible had proven this to me.
If you want a little more range from time to time unscrew the 150mm whip and screw on a longer stainless antenna.

Installed or handheld?
Answer to that is both.
Handhelds work well but an installed set is always there, not the battery is flat or its in the van or the glove box or anywhere else other than in arms reach. I use both but while driving there is only one "best" choice.

Antenna position?
It has been proven that as high and smack in the centre of the ground plane (metal structure of the vehicle) IS the best but rarely practical. But once you accept the fact that reliable long range operation isnt the nature of this band then spending too much time trying to achieve perfection is just a waste of time, cover the basics, free space for 300mm around the antenna and your good to go. The performance difference from poor antenna position is most often caused by the radio derating because of a poor SWR because of surrounding metal objects close to the antenna.
If you can reliably get 10km in all directions out of your in car it will do everything this class of radio is designed to do in a legal mobile application.

If your going bush and need reliable comms take a sat phone or at least an airband handheld. The sat phone will also transmit your exact co ordinantes in an emergency.

Antenna debates always boil down to the practical side and the theoretical side.
Which is right?
Answer both, and neither.
Only theoretical antennas can be the same.
There are too many variables in practice for any two antenna systems to be the same. Even the same antenna on different days will perform differently.
Debating in forums is pointless because most of the time those that say the most only know what they repeat off the net.
This come up around a campfire one night and as a test I asked a simple question and none of the "experts" had Google to fall back on. The most basic principle of gain and nobody had a clue but they were all convinced that their choice of antenna was the best.
Antennas are a science and what most of us, including myself, know is like comparing a fire cracker under a baked bean tin to the launching of the voyages spacecraft's.

William.
Are you know confused and can't make a decision.
If a recognised quality unit or a high end, high price unit is purchased, both will work the same with a decent aerial. You decision as the the outlay. Not sure if most who have replied have actually used one over a large distance or relatively short distance. Hard to sort out reality.

Thank you every one for their replies.
I don't need the radio for emergency comms and am aware of antenna placement.
UHF for me is while travelling to be able to hear from oversize convoy drivers and such and in the deserts to broadcast and listen for other vehicles. ( even though some desert travellers seem unaware of the need for this).
I am interested in the hand held option with a fixed antenna or magnetic mount.
Once again thank you every one for sharing their thoughts on this subject.
If I am missing something obvious please post your thoughts, I'm not going to discount any thing.
William