Whether you're tackling remote 4WD tracks, keeping a convoy together, working a regional job site or heading bush with the family, a UHF CB radio is one of the most reliable ways to stay connected when mobile coverage disappears. But if you're new to two-way radio, the jargon can be a lot: duplex, simplex, CTCSS, gain, repeaters. It's simpler than it looks.
We've pulled together the questions Australians ask us most, with plain-English answers and a few pointers to the right gear for the job. Jump to the section you need, or read the lot and become the most useful person in your convoy.
UHF CB Basics
What is UHF CB radio?
UHF CB (Ultra High Frequency Citizen Band) is a free, licence-free two-way radio service that Australians use to talk to each other over short to medium distances. It runs on the 477 MHz band and is managed by the Australian Communications and Media Authority (ACMA). It's the standard for 4WDers, truckies, farmers, campers and anyone who needs dependable comms where phone signal is patchy or non-existent.
Do I need a licence to use a UHF CB radio?
No. UHF CB operates under an ACMA class licence, which means anyone can use it without applying or paying for an individual licence, provided you use approved equipment and follow the channel rules. Every Oricom UHF CB radio is designed and approved for use in Australia and New Zealand, so you're good to go straight out of the box.
Why do we use UHF CB in Australia?
UHF CB gives clear, crisp local communication without the long-distance interference you get on other bands, and it's free to use. Because it's an open, shared platform governed by Australian standards, radios from different brands all talk to each other, as long as everyone's on the same channel. It's worth knowing that radios approved for Australia generally can't be used legally overseas, as other countries use different frequencies and standards.
What's the difference between UHF CB and 27 MHz CB?
Both are part of the Citizen Band radio service, but they behave very differently. The older 27 MHz band uses AM transmission and is prone to long-distance interference. UHF CB uses FM on the 477 MHz band, delivering clearer, more reliable local communication. For virtually all modern touring, work and recreational use in Australia, UHF CB is the way to go.
Channels: What They Mean and How to Use Them
What are the 80 UHF CB channels for?
Modern UHF CB radios give you 80 channels to work with, so there's almost always a clear one to talk on. Some are set aside for specific purposes, and using them correctly keeps the airwaves clear for everyone:
- Channels 5 and 35 are reserved for emergencies only. Never use these for a chat.
- Channel 11 is the "call channel," used to make contact with someone before you both move to a free channel to talk.
- Channels 22 and 23 are reserved for data and telemetry, so voice transmission isn't allowed.
- Channels 1–8, 41–48 (and 31–38, 71–78) are repeater channels, used in duplex mode.
- Channel 40 is the informal truckies' and highway channel across much of Australia.
- Channel 18 is commonly used by caravanners and campers.
- Channel 10 is widely adopted by 4WD clubs and convoys, particularly in national parks and on popular tracks.
What is simplex and duplex?
This one sounds technical but it's straightforward. Simplex means your radio transmits and receives on the same channel, which is how most direct radio-to-radio conversations work. Duplex means your radio transmits on one channel and listens on another, which is what lets you talk through a repeater to dramatically extend your range.
How does a UHF CB repeater work?
A repeater is a transmitter-receiver combination installed somewhere high, like a hilltop or tall tower. Because of its elevation, it can pick up your signal and rebroadcast it far beyond what two radios could manage on their own. When you select a repeater channel in duplex mode, your radio transmits 30 channels up (for example, you talk on channel 31 but hear the reply on channel 1). The repeater does the rest, catching your signal and pushing it back out to everyone in range. This is how you keep in touch across serious distances in the high country or remote regions.
Range and Performance
How far will a UHF CB radio transmit?
It is a difficult question to answer as there are many variables at play. UHF CB Radio operates on line-of-sight. Whether it be a handheld, or an in-vehicle radio the transmission or the receive distance is affected by the radio’s transmit output power, antenna height, antenna gain and the terrain.
How can I get better range?
Three things make the biggest difference: power, antenna and elevation. Run the maximum legal 5-watt output, mount the right antenna as high as you can, and remember that height is your friend. This is also why a fixed-mount radio with a properly mounted external antenna will almost always outperform a handheld in open country.
Is 5 watts the most power I can have?
Yes. In Australia, UHF CB radios are limited to a maximum of 5 watts transmission power under the ACMA class licence. Any radio advertising more than that for UHF CB isn't legal for the band. All of Oricom's 5-watt radios, like the DTX600 waterproof handheld and the fixed-mount UHF390R, run at that legal maximum for the best possible range.
Choosing the Right Radio
Should I get a handheld or a fixed-mount radio?
It comes down to how you'll use it.
Handheld radios are portable, quick to grab and don't need installation, making them ideal for spotting, hiking, camping, working on foot or as a second unit alongside your vehicle radio. Oricom's handheld range runs from compact low-power units up to the rugged, waterproof 5-watt DTX600.
Fixed-mount radios install permanently in your vehicle, run the full 5 watts, and pair with a proper external antenna for the best range and clarity, which makes them the pick for serious touring, convoys, trucks and work vehicles. Explore the fixed-mount range to see the options.
For the most versatile setup, many people run both: a fixed-mount in the vehicle for range, plus a handheld for when they're away from it.
What's the difference between a 1 Watt, 2 Watt and 5 Watt handheld?
Power roughly translates to range. A 5-watt handheld gives you the greatest range; a 2-watt typically delivers around half that; and a 1-watt (or 0.5-watt) unit less again. Lower-power radios like the UHF768 twin pack are compact, affordable and perfect for keeping tabs on the kids around camp or on a hike, while a 5-watt unit like the DTX600 is the one to reach for when you're heading properly off-grid.
Do I really need to upgrade from a 40-channel to an 80-channel radio?
Your old 40-channel radio will still work, but there are real benefits to upgrading. You get double the channels, so more room to find a clear conversation, and modern 80-channel narrowband radios deliver cleaner audio. Older 40-channel transmissions can also come through distorted or unexpectedly loud on newer radios because of the difference in bandwidth. If your gear is ageing, an upgrade is well worth it.
Which Oricom radio should I buy?
It depends on your adventure. As a quick guide:
- Just getting started or need a second unit? A handheld twin pack is affordable and instantly useful.
- Serious touring, 4WDing or convoy work? A 5-watt fixed-mount like the UHF390R with a quality antenna is the go.
- Want to monitor two channels at once? The UHF350DR and DTX4200XP offer Dual Receive, ideal for keeping an ear on both the convoy and the highway channel.
- After a complete, ready-to-go kit? The bundle packs pair a radio, antenna and accessories in one.
Every fixed mount Oricom UHF CB radio is backed by a 5-year warranty and local Aussie support. Handheld radios include a 3 year warranty.
Antennas
Where's the best place to mount a UHF antenna?
Because UHF CB is line-of-sight, height is everything. As a rule, the higher you can mount your antenna on the vehicle, the better it'll perform. A bullbar or roof-edge mount that gets the antenna up above the roofline usually gives the best all-round results.
What's the difference between high-gain and low-gain antennas, and do I need both?
Gain describes the shape of the signal your antenna radiates, and different terrain suits different gains.
- The 3dBi antenna has a wide pattern, ideal for undulating terrain.
- 6.5dBi antennas are popular due to their performance over distance on flatter or slightly uneven terrain.
Plenty of serious tourers own one of each and swap depending on where they are. Browse Oricom's antenna range and antenna whips to match your setup to your terrain.
Can I connect a handheld radio to an external antenna?
Some handhelds can connect to an external antenna, which can noticeably improve performance, especially from inside a vehicle. Check the specifications of your specific model to confirm compatibility and the connector type. DTX600 for example, can be connected to an external antenna through the use of an optional connector.
Features Explained
What is CTCSS / DCS?
Both are ways of filtering who you hear. CTCSS (Continuous Tone Coded Squelch System) adds an inaudible tone to your transmission; radios set to the same tone stay quiet until they hear it, so you only hear your own group. DCS (Digital Coded Squelch) does the same thing using a digital code instead of a tone. Neither one is "better," and importantly, neither stops other people from hearing you if they're on the same channel; they just stop you from hearing traffic you don't want. Oricom radios include a generous set of CTCSS and DCS codes to help you cut through the chatter.
What is scanning?
Scanning lets your radio automatically sweep through channels looking for activity, so you don't have to flick through them by hand. When it finds a conversation it pauses so you can listen or join in, then continues. It's handy for finding where the action is or keeping an ear on multiple channels at once.
What is Dual Receive?
Dual Receive lets a radio monitor two channels at the same time, a genuinely useful feature if you want to stay on your convoy's channel while also keeping tabs on the highway or truckies' channel. It's a standout feature on models like the UHF350DR and DTX4200XP.
What is Instant Replay?
Instant Replay records recent incoming transmissions so you can play them back if you missed something, whether it was a track direction, a callout or a hazard warning. It's a feature you'll find on radios like the UHF360R and UHF395P.
Quick Troubleshooting
Why can I hear other people but can't talk to them?
First, check everyone is on the same channel. If you're on a repeater (duplex) channel, make sure your radio is set correctly for it. Also check that a CTCSS or DCS code isn't set differently across radios, as mismatched codes are one of the most common reasons a group can't hear each other.
Why is my reception noisy or cutting out?
Usually it's range or line-of-sight related: terrain, distance or a poorly positioned antenna. Check your antenna connection is secure and mounted as high as practical, and remember that hills, buildings and dense bush all eat into range.
Why am I picking up strangers' conversations?
On a shared, licence-free service, that's normal, as UHF CB channels are open to everyone. If you want to reduce unwanted chatter within your own group, set a common CTCSS or DCS code so your radios stay quiet unless someone in your group is transmitting.
Still Not Sure? We're Here to Help
Choosing the right UHF setup should be easy, and getting it right the first time means clear, reliable comms wherever you're headed. Browse the full Oricom UHF CB range, grab a ready-to-go bundle pack, or get in touch with our Australian support team for a personalised recommendation.
Proudly Australian owned and operated since 2003, and backed by a 5-year warranty on our fixed mount UHF CB radios, Oricom builds gear designed and tested for real Aussie conditions.
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