Why use an HF Radio?

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An HF radio is primarily designed to enable long distance communication in areas of Australia where the telephone network is not available. Not only is it inexpensive to operate, it also provides access to free-to-air network broadcasts and services and most obvious of all, instant connection to the Royal Flying Doctor Service (RFDS).

Your use of the airwaves is governed by Australian Communications and Media Authority. The ACMA assigns transmission rights to frequencies and can issue certain types of licences to groups or individuals that authorise transmission on these frequencies, however anyone can listen to frequencies without a license provided they do not transmit.

HF Radios have long been an obvious consideration if you intend to travel throughout remote regions of Australia or if you are interested in receiving any of the following services:

• RFDS emergency contact


• To communicate over long distances (from as little as a couple of kilometres, or from one side of the country to the other)


• Making telephone calls direct from your vehicle to any phone line


• "Free to air", and Network operated radio broadcast and transmissions


• To find someone who is near you who can pick up a spare or assist you on your way (if used in conjunction with an optional Radio Network Service)

If however, you only need close distance communication, or vehicle to vehicle communication a UHF radio is better.

Emergency Transmission

To assist in an emergency, an HF radio will enable you to connect you to all the RFDS frequencies to seek medical aid (provided either by an operator over the airwaves or if necessary to coordinate a rescue). As a minimum you will be able to use the Emergency Alarm Call Button on your radio to make contact with the base station nearest to you. Operating hours vary depending on the base, although a 24 hour emergency call watch is maintained.

Some Radio Networks, such as the 4WD Radio Network VKS737 may also be available to assist in coordination of other members in search/recoveries who might be nearby a person in distress.

Joining a Network

You need to be licensed by the ACMA for the frequencies you intend to use. You may elect to join a Radio Network which carries inbuilt licensing for their own frequencies. You do not have a specific license yourself, but are authorised to use the license of the network through your membership.

The most relevant radio network for outback travellers is the Australian National 4WD Radio Network Inc. (VKS737). The primary role of this network is to provide safety orientated HF radio communications for travellers in remote areas. To join the Australian National 4WD Radio Network Inc. (VKS737) you will need to purchase a 12 month Member Subscription.

If you are a member of this network then you will know what channels and frequencies you can listen in to hear member-base operator discussions. Some people find this very entertaining and you may often pick up relevant track information and safety warnings. The Network will also run scheduled broadcasts at specific times of day for members to listen to relevant reports (weather etc) and offer many other related services.

Receiving Radio Broadcasts

The HF spectrum covers the range 1.7 to 30 MHz, which means that you can receive numerous broadcasts including Radio Australia, BBC World, School of the Air, even Voice of America and of most relevance to outback travellers you can listen to across the various frequencies to member and base operator communications on the VKS737 4WD Radio Network.

Radio Telephone

Your HF radio unit, can also be used to make telephone calls, for which you will need to subscribe to a direct dial service. There are a couple of Direct Dial HF Radio Telephone Network Services in Australia, offering a range of call plans to suit your particular needs. Yearly access fees are often bundled with pre-paid calls. Look for a network with sufficient base stations around Australia allowing you to make telephone calls directly from your HF radio to any telephone or mobile phone in Australia. Some call plans also include free RFDS and Police direct selcall contact and free emergency assistance by 24hr operator. Note that these calls are still made over the radio network, but connect into the telephone/mobile network.

A couple of things to consider when deciding if you really need to make phone calls:

• A "phone" call from a radio is broadcast over radio waves. Anyone with a radio tuned to (or scanning) that frequency can listen to the conversation


• Telstra still provides public phone booths throughout all towns and service centres


• Some HF radio networks offer a message relay service, which you may consider a suitable alternative

Email, Fax, Data and GPS tracking

Recent advances in technology have enabled email, fax, data and even GPS tracking functions to be possible via HF radio. Older HF units will need modification or additional hardware and/or service agreements to enable usage and cover costs. However many modern HF radios have Global Positioning System (GPS) software installed by the maker as a standard feature. HF - GPS interface means that in theory your location coordinates can be transmitted by your HF, to a remote, suitably equipped station.

Keep in mind that these functions will be limited by the HF spectrum so don't expect the same speeds and capability that you're used to from LAN/WAN telecommunications.

 How does an HF Radio work?

An HF radio is a high powered radio transmission and reception system designed to cover large distances. It is a high frequency single side-band communications system. Unlike CB and UHF radios, which have an effective working range of up to 5km, the HF radio will operate over many thousands of kilometres.

 How much will it cost?

Equipment Purchase and Installation

The capital cost of purchasing and installing an HF radio system is a once off investment. A new HF radio will cost close to $3000 and since they've been used for a few decades now, there are many second-hand systems on the market varying in value depending on the functions and age of the unit. There have been many changes in technology made to the newer models such as auto-tuning antennas, GPS interfaces and modems enabling email/fax capabilities so be sure to check out what you're buying. There are three main brands of HF radio used in Australia, namely Barrett, Codan and Q-mac. All are Australian made by Australian companies, in fact it may surprise you to learn that Australia is the world leader in HF communications!

An HF radio purchased for the application of using in a vehicle requires installation similar to your stereo. A complete HF radio system includes a number of units - an antenna and aerial (can be mounted at the front or rear of the vehicle); a receiver which needs to be fixed in a dry, secure position receiving power from the vehicle's battery and correctly wired to ensure operation in an emergency situation (noting that they use high current when transmitting); and a handset with microphone that needs to be secured to the dash, or a roof console for ease of operation by either driver or passenger. The costs of a professional installation need to be checked - normally this is done at the place of purchase for an additional fee that includes some basic training. The installation should be done by someone who knows what they're doing to ensure safety, and effective operation. If you are happy to install it yourself, you might like to read our Installation Tips & Photos.

Call Costs

Probably the most attractive feature of owning an HF radio is that calls are free! However, before you get too excited over that, remember these are not calls in the sense of telephone calls. Radio calls are transmissions made over the HF radio spectrum on channels that are programmed into your set (Channels are assigned to frequencies, as they are with your television set). To change or add new frequencies you need to pay to have a programmer re-set your HF Radio - they usually have special equipment to do this. Any frequency may be added to a radio for listening purposes however you must be licenced (user-pays) to use the frequency before you can legally transmit or talk. For this reason, joining a network such as VKS737 enables you to transmit on the frequencies owned by them - this is covered by the fee you pay to join the network.

Optional Services

You can purchase various hardware and subscribe to other services to enable additional functions to be possible via your HF radio. These features include direct dialling to a phone line, sending emails and faxes, and using GPS functions. Be aware that each service will have additional costs associated with using these features.

 Disadvantages & Limitations

Ease of Operation - the trade-off for gaining the ability to obtain free calls from your HF radio is learning how to use it. And for some people, it just isn't easy. The most obvious issue is that you cannot talk and listen at the same time, unlike talking on a telephone. This takes some practise and getting used to. However the most complex thing to learn when using an HF radio is how to use the various features such as Making a Voice Call, Selcall, Beacon Call and Scanning - basically you have to learn how to use the buttons and knobs and many of them will be multi-purpose buttons so you are going to have to get out the user manual and read it, practise it, and even getting so organised as to prepare a cheat-sheet in your vehicle for ready reference.

Similarly, anyone who attempts to call you on the HF radio will need to learn certain protocols and calling tips to get the call through. For vehicle to vehicle calls using HF you use the Selcall feature - you need to know the Selcall number of the person you are dialling. Networks such as VKS737 will normally make the member list available.


Another important note is that long social radio discussions are infact a highly inappropriate use of this service, particularly if using one of the assigned frequencies to a club or network. Take note of the protocols if you join a network - they will have guidelines for your use of the airwaves. Bear in mind that suitable frequencies are usually limited for the number of people trying to use them so clogging up the airwaves with unnecessary banter is irresponsible.

 Where to get help

For people that are new to using an HF Radio, there is plenty of information available to help you overcome the most common operational issues. You can: see related posts in the Forum; view the various websites of related network services and even manufacturers; or purchase the HF Radio Guide for Travellers (a booklet produced by members from the VKS737 4WD Radio Network and sold via ExplorOz - see below).

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