Benefits of HF Radio

HF Radio has been around since Marconi established transatlantic communications in 1901, and without his radios the Titanic tragedy almost exactly 100 years ago would have been even worse.

HF radio occupies the spectrum from 3 to 30 MHz and it’s still very popular today and with good reason. HF signals can carry effectively over huge distances, from hundreds to thousands of km, and occasionally around the world.

It was the low cost and simplicity of HF radio that provided the backbone for School of the Air communications services for more than 50 years and it still does for the Royal Flying Doctor Service, and outback travellers emergency networks.

CB radios and mobile phones cannot provide the same outback communications capability although CB’s are useful in short range (eg convoy) situations and the Telstra NextG service is very useful near towns and major highways.

RADIOS, ANCIENT AND MODERN

Modern radios can now provide a variety of communications services, such as email, SMS, telephone connections, Selcall and GPS position reporting, but the original principles of an HF radio are still embodied in radios from companies such as Codan and Barrett, with designs and technology that lead the world in HF communications.

If your radio doesn’t have provision for GPS position reporting, or just for increased peace of mind, taking an EPIRB with you will ensure automatic initiation of search and rescue services should you ever find yourself in “grave and imminent danger”.

New HF radios can cost up to $3,500 but since the principles of operation have not changed in 50 years, even secondhand radios up to 30 years old are still a very viable alternative. They are simple and reliable, and with the addition of a Selcall microphone, they can replicate many of the features of more modern radios.

A Codan 7727 of the 70’s and 80’s still doing sterling service

A Codan 8727, a later version but technically similar

A Codan 7727 with a remote control box

Current radios are microcomputer controlled with 100’s of channels programmed into them and a plethora of features, but fundamentally they do the same job now, and with the same transmitter power and communications range, as a 1970’s radio.

The HF-Radio.com.au store is a useful source of new and refurbished radios and information. Just ensure any radio bought has Selcall facilities.

MAKING CONTACT

A satellite phone, just like a home phone or mobile, can generally only be used to call a single recipient, whereas a call made on an HF radio can be heard by almost anyone whose radio is tuned to that frequency. And since there are just a few well established contact frequencies offered by various outback radio clubs (see table below), the chances are high that a call would be heard, probably by several listeners.

While this might not be considered very private, in an emergency situation, or if you need roadside advice, or to pass on a message to folks back home, this can be a blessing.

Few listeners would pass up a call for assistance or a request to relay a message or even just to chat with someone whose been traveling in a remote and lonely location for days.

Recently, the RFDS ceased monitoring the red Emergency Button fitted on the front panel of most radios and now only responds to Selcalls, so it’s important that any radio used in the outback has Selcall capability, which most radios from the 90‘s onwards do have. RFDS Selcall and emergency telephone numbers are on the Flying Doctor website here and the RFDS has a close association with the VKS737 Australian National 4WD Radio network.


Useful articles on HF radio Communications are on the Exploroz website here and the Beadell Tours website here.

FAMILIARITY IS THE KEY

Using an HF radio regularly is a good way of keeping in touch with other people who are out there doing much the same as you are, but importantly, it also confirms, that your radio is working and will be ready if or when you have an emergency.

And because it might be you that needs help, ensure that all other members of your group, especially the younger members, are familiar with operating the radio, including erecting and connecting the antenna, choosing the right channel and making a Selcall.

Making the first call can be a bit daunting but base operators are always happy to offer advice to people new to HF radio and it soon becomes second nature to them.


Outback HF Radio Clubs


VKS737 7 Channels, 14 Bases, some in RFDS bases.
HF Radio Club 9 Channels, 4 Bases
HFOZ 5 Channels, 3 Bases
Bush Telegraph 5 Channels, 4 Bases

Safety and Emergency Equipment on our Oka

Important Note:

If you have an HF Radio, first read this document regarding current (2011) changes to the RFDS emergency call procedure using an HF radio on the VKS-737 network.

If you have a Satphone read this document for accessing the RFDS.

If you don’t have either an HF Radio or Satphone in your vehicle (or travel group) you are putting yourselves at unnecessary risk when away from major towns or highways.

Refer also to these outback safety documents:

• RFDS Safe Outback Travel (straight forward stuff from people who should know),
• WA Police Bushcraft and Survival Guide (120 pages of very useful stuff, download and read before travelling, and put a copy in your Emergency Rucksack).
• Suzi and Ruedi’s insight into safe traveling in their Oka.

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Safety and Emergency Equipment in our Oka:

Apart from the usual recovery gear (jacks, towropes, hub adaptor, spade, sand mats etc, see our separate post on our Recovery and Maintenance Gear) we also carry the following range of safety gear and emergency equipment in our Oka.

Electronic/Electrical Equipment:

1) 406MHz EPIRB (this should preferably be one that includes a GPS (MT406G) for faster and more accurate positional location, (minutes, not hours, and to 100 m accuracy, down from 5 km), but these were unavailable at the time we bought ours).

• The EPIRB should be tested regularly, but activated only in cases of grave and imminent danger. Also ensure that emergency contact (next of kin) details are registered with ASAR and up to date as they will be contacted before any SAR activities are mounted, to avoid false alarms. You can also upload your planned trip route to assist with verifying an emergency call. Both can be done via the Beacons page following registration.

2) Strobe/Flare Flashlight (orange) for attracting attention at night.

Strobe/Flare flashlight and EPIRB on quick-release mountings

The strobe/flare emits a powerful orange flash which can be seen for many km after dark. Test it regularly. [Eflare EF300 Safety Beacon, available from Exploroz].

3) HF Radio plus a range of antennas:

• Tapped whip for all VKS-737 and RFDS frequencies,
• Super Rod 9m whip for 8022 kHz, (see here) plus a 4.5 m extension cable to tune it to 5455 kHz (and most RFDS channels which are around 5 mHz),
• Long wire emergency antennas for 8022 and 5455 kHz, (for 8022kHz, length 8.88 metres/29.17 feet, for 5455kHz, length 13.06 metres/42.90 feet, thick insulated wire such as used for garden lighting).

[Important: Regarding the Red Emergency Button on your radio, from December 2010 (ie from NOW on), use of the Emergency Call Button facility has been phased out by the RFDS and will no longer be monitored, (see the press release here and the VKS-737 media release here).

So if you have a Selcall facility use that, but you’ll need to know the numbers. Otherwise call a VKS base during sked times, or make a broadcast call, someone will likely be listening and can forward a message to the authorities. If you have a Satphone call the RDFS direct on these numbers. If that fails, in a real emergency, activate your EPIRB.]


Note: Call in (don’t just listen) regularly at sked times for a radio check. This will provide confidence that your radio will transmit effectively when needed. It’s also very important that all party members, especially your spouse and kids, know how to use the radio, including erecting and connecting the emergency antenna.

9m SuperRod antenna erected

4) Moving map computer based navigation system (Oziexplorer pc software with 250,000:1 scale maps of the whole country (NatMap series from Exploroz here). These plus a GPS will give you local positional and terrain information to a few metres resolution, depending on the age of the maps. (If you are a Mac person, Oziexplorer runs well on a MacBook under VirtualBox/XP),

• If you know the route you are taking, it’s possible, but a bit awkward, to pre-record your track on Google Earth for later replay. It might be useful to actually see what is just beyond the next hill or sand dune, or if the track you are on actually leads anywhere useful, but bear in mind Google Earth images may be out of date (eg summer vs winter) or poor resolution.

5) GPS x 2, a USB module (Globalsat BU-353 Mouse GPS) for connecting to our moving map computer system and a hand-held one (Garmin Extex Venture) for use when walking (can also be connected to the computer).

6) Telstra NextG phone. T100, effective and cheap ($49 from Dick Smith or Telstra shops), so you can afford 2 of them, with modem facilities (T100 works well as a modem using Telstra’s JoinMe application, but is fairly slow), plus 2 external antennas (a whip and a Yagi).

• The Telstra NextG network provides the widest coverage of all networks, but not all the country is covered.
• A NextG phone with the Telstra Blue Tick and provision for an external antenna connection is necessary for best coverage.
• Note: not classed as emergency equipment but surprisingly useful in many remote areas and with a longer range than a hand-held CB. (But see note below),

7) Hand-held CB radios (GME 610 x 2). Note: not classed as emergency equipment but useful for convoys or when walking in groups. Always take one with you if you wander off alone but ensure both are turned ON, obviously. I’ve modified ours to enable a full size, roof/bull bar mounted CB antenna to be connected, for longer range.

• Useless for long range emergency communications. (See note below).

Note: CB Radios and Mobile phones cannot be relied upon in all situations, especially away from major towns and highways. Always carry an HF radio or Satphone as well as CB/phone.

8) Emergency Engine Stop Button. If you (or quite possibly your passenger after an incident) need to stop the engine quickly, or if you break off the ignition key or can’t access it, an Emergency Stop Button can be useful.

• We have a switch in the centre of the dashboard which simply cuts off the 12v supply to the fuel cut off solenoid on the injector pump. I sometime use it if the turbo time won’t switch off. It can double as an immobiliser as well, as the engine can’t start unless the solenoid is energised. It’s also useful for spinning the engine without it starting, such as building up oil pressure after an oil change before applying a load to the bearings.

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Mechanical/Non Electrical Items:

1) Fire Extinguisher x 2, a larger 2 kg plus a 1 kg powder extinguisher. Two is safer than one in case one doesn’t work when needed.

• They should be shaken up at least annually to avoid the powder packing down hard though vehicle vibration. We keep them just inside the door so they can be easily accessed from outside as well as inside. Ideally, one should really be nearer the cooker.

2) Fire Blanket. We have one located near the cooker.

• We had to use it once when a plastic mat got stuck unnoticed to the bottom of a saucepan which was then put back on the stove. Flames took hold and black acrid smoke filled the Oka surprisingly quickly. The blanket effectively stifled the flames but we had to evacuate while the vent fans removed the smoke. We had acesss to the fire extinguisher but luckily it wasn’t needed, they can make an awful mess. The smoke alarm also went off adding to the drama.

3) Smoke Alarm. Ours has a light inside as well since it can be very dark at night when camped in remote locations.

• However, in the confines of a motorhome, false alarms while cooking can be a real but unavoidable nuisance, even with an extractor fan. I have fitted our alarm with an electronic inhibit function which times out after around 40 minutes, long enough to cook a meal, or it can be manually reset earlier. (See this electronics article, and scroll down to “Temporarily silencing a smoke alarm”. As far as I know this is not available commercially, I built by own).
• The non-recomended alternatives are to cover it up (shower cap) or take the batteries out of the alarm, but both options are a serious safety risk until they are returned to normal operation. Chubb/Quell sell smoke alarms with a 10-15 minute “hush” function but that is not long enough and anyway they still activate if the smoke density subsequently increases.

4) Drinking Water Filter


Clean purified drinking water can prevent many of the annoying stomach upsets caused by drinking water from dubious sources. Even clear running water can harbour dangerous microbes.

• A 0.5 micron water filter will filter out most of the nasty chemicals and bacteria which can cause digestive tract infections.
• When bush walking we also carry water bottles fitted with small outlet filters. This allows us to refill them from any source if we really had to. But don’t use cordial or similar in these bottles, it will clog up the filters immediately.
• We also carry water purification tablets available from camping and outback stores.

In an emergency, water can be purified using SODIS, a cheap Solar Water Disinfection method, pioneered by the Swiss. See this site for simple instructions. I was put on to this method from Suzi and Reudi’s website but their link is dead.

• Fill one or several clear PET plastic  or clear glass bottles with contaminated water (filtered to remove as much cloudiness/turbidity as possible),
• Leave (lying down is best) in full sun for at least 6 hours, protected from wind and kept as hot as possible to aid the process.
• This will kill the bacteria in the water, see these FAQ’s.
• Drink direct from the bottle to avoid re-contamination.
• Algae can grow during and afer this process but are apparently NOT harmful.
• Purified water can be kept for long periods in sealed bottles without re-contamination.

5) Snake Bite treatment. In remote locations, a serious snake bite can prove fatal.

• Taking supplies and instructions for snake bite treatment (using the vital Pressure Immobilisation Bandaging procedure) can be a life-saver.
• Refer to a separate Snake Bite Discussion Notes page here).

6) Lifebuoy. If you regularly swim, or camp with children near water, a Lifebuoy or similar would be essential.

• We don’t have one but we would have floating items (eg foam cushions) we could throw in. A simple “throw bag” device with a rope attached would seem a good investment and are available here or here.

7) Comprehensive First Aid kit and manuals, (see here for outback First Aid Kit suggestions),

     7.1) These are the first aid/medical items in our kit, roughly in the order we most use them:

• Prescription medications
• Vitamin B1 to reduce the effect of mosquito bites
• Insect repellant
• Antiseptic Cream
• Lots of Band Aids (larger cloth types stick on better and last longer than the small thin plastic bandaids which don’t stick to sweaty skin)
• Insect bite/sting cream/spray
• Antihistamine (Zyrtec) tablets to reduce the itchiness of sand fly bites
• Sunblock/sunburn cream
• Headache tablets
• Cold/Flu tablets
• Anti-fungal cream
• Indigestion tablets
• Deep Heat for muscular pain

     7.2) These are items we also carry but seldom use:

• Antibiotics (only for emergency infections like toothache and inflammation of small wounds, seek medical advice for more serious infections)
• Immodium for stomach upsets/diarrhoea (our water filter prevents most of these)
• Ural tablets for urinary tract infections
• Bonjela for sore gums
• Throat lozenges
• Eye wash
• Ear drops
• Bandages
• Wound closures
• Ankle/Wrist/Knee straps
• Water purification tablets

8) Orange “V”-sheet for daytime visibility and also weather protection (available from marine suppliers, eg Whitworths, Bias Boating),

9) 4.5 M Fibreglass Sand Flag Pole. The base is permanently mounted on the front bullbar and the pole installed to provide a visual warning to oncoming vehicles when climbing steep sanddunes crests, or when it’s essential for us to be seen such, as a breakdown at a dangerous location. Can also be used for hoisting radio aerials and emergency flags.

10) Emergency Rucksack, pre-packed, or which can be quickly packed with emergency supplies in case of fire, or major accident where we had to abandon or escape from the Oka quickly. We keep seldom used items in the rucksack all the time for a quicker getaway.

Contents:

• EPIRB, strobe/flare flashlight, hand-held GPS, hand-held CB radios, phone, spare (charged) batteries,
• Headlight/torch, reading glasses, compass, maps, whistle, mirror, “V”-sheet,
• First aid stuff, insect repellant, sterilisation tablets, emergency blanket/shade cover,
• Matches/lighter, collapsible plastic bucket, rope, Swiss Army knife,
• Water bottles (2 x 2 litres min., with filter elements), dry food (sweets/biscuits/dried fruit),
• Hats, jackets, ponchos, sneakers,
• Keys, money and cards (wallet/purse), paper and pen, survival checklist, sundry items.

Note: In any eventuality, stay close to the vehicle where you can more easily be found.

10) Lethal Flying Objects. Although not actual safety equipment, we do ensure that everything is securely fixed down and can’t easily break loose in an accident to become lethal flying objects. This makes sense for travel over rough tracks anyway.

• There are bulkheads behind both seats to protect our heads and large items (eg fridge, cooker, water tanks (including the toilet), gas bottles, fire extinguishers, HF radio) are kept low down and have steel frames bolted to the vehicle sub-chassis and/or side frames, and they have never moved. Steel frames may be heavy but weight=strength=safety. [Note: Small bolts (anything under M6) and pop rivets can be points of failure, and also stainless steel should be avoided as it’s much weaker than normal high tensile steel].

• Smaller items (bottles, cans, utensils, and tools-which can be very heavy) are kept in compartments that only open sideways, so they can’t fly forwards. Our rear tailgate section contains heavy tools but has a fixed bulkhead fitted in front of it. In other types of vehicles a cargo barrier and/or tie down straps would be a must.

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Things we don’t carry in our Oka:

Satphone (expensive, inflexible (can’t broadcast widely), would duplicate the HF radio for some applications), would be useful to call the RFDS,

Winch (heavy to carry around and would seldom be useful, except to pull other people out).

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Nice to Haves:

Programmable HF radio (our existing radio is old and reliable but only has 6 channels and no Selcall facilities). Yes, it does now. We have recently fitted a Jenal SC2 Selcall microphone to our radio, so we can now directly contact any RDFS base via selcalls through any VKS base.
I have also modified the radio so we can receive ABC and BBC shortwave broadcasts (amongst others).

SuperRod 9 Metre Whip Antenna for HF

We use the VKS737 HF radio network to keep in contact with the world while we are camped in remote locations.

I have previously used a fairly short (2m) tapped whip antenna but recently installed a 9m fibreglass whip antenna which, at a 1/4 wavelength, is the optimum length for using Channel 2 on 8022 KHz.

The 9m SuperRod in operation on our Oka

The antenna is based on a 9m, 9 section, telescopic fibreglass fishing pole, but with a wire inserted up the middle. They are called SuperRod Antennas and I got mine from The Electric Bug in Adelaide for around $200 without any mounting hardware, but a cheaper alternative could be to make one using a fishing pole from angling shops. (See here where you can buy 9m bare poles for around $40 plus freight, and fit the wire yourself, see here for some assembly ideas).

The wire doesn’t have to run up inside the antenna, it will work just as well if the wire is wrapped around the pole, or if it is just attached to the tip and the pole used as means of getting it vertically into the air. It just looks neater inside. The pole doesn’t even have to be 9m long either, only the wire has to be that long.

Whilst the antenna works well, there are a few of challenges to its installation and operation:

• Mounting: It needs a sturdy mounting point on the bull bar or similar because, although it’s not heavy, as it moves around in the breeze it places a considerable strain on its mount. It should not be used on a moving vehicle while raised.

• Antenna Wire: When collapsed, the 9m of wire needs to be coiled or wound up to keep it straight and tidy. A kinked wire won’t run up or down the antenna smoothly.

• Erecting: (Important: first read the Power Line warning at point 7 below. Note this sobering story from the ABC). The sections must be extended tightly and “screwed” into each other as the antenna is being erected, or they can slide down inside each other, either during operation as the wind blows or as you are lowering the antenna, trapping the wire and loosing their telescopic sequence.

• Lowering: The wire must be pulled gently and continuously out of the bottom of the antenna as each section is separated, or it will get trapped and kinked in the bottom section which is frustrating to unravel and the wire can break.

• Connecting: The antenna needs connections made to the radio lead. It doesn’t just plug on.

• Frequencies: It primarily intended for Channel 2 (8022 KHz) and needs some mods to work on Channel 1 (5455 KHz) or RFDS frequencies.

• Power Lines and Lightning: It’s so tall it’s a power-line and/or lightning risk.

I have experienced all of the above problems and modified the antenna and mounting arrangements to minimise them.

1) Mounting the Antenna

To mount the antenna, I fitted a length of 50mm PVC pipe, to hold the lower section of the antenna, to an aluminium frame which then slides into a holder, made from aluminium rope track, mounted on the bullbar using 50mm U-bolts. The pipe has a cap on the bottom to hold the antenna but with a hole in it for the wire to slide through. The whole assembly can be removed, with the wire wound up on an attached reel, for storage inside the Oka.

The mounting using aluminium rope track on the bullbar.

The SuperRod stored safely in the Oka.

 

 

2) Keeping the Wire Tidy

After lowering the antenna and extracting the wire, you are left with a 9m tangle of wire on the ground (actually only 8m since 1m is always inside the antenna).

To tidy this up I fitted a cheap hand fishing reel to an aluminium plate with a simple handle to wind up the wire as it is being pulled out, which is a lot easier with 2 people. A notch/slot in the reel holds the connector in place as the wire is wound up.

The SuperRod mounted on the bullbar, with a hand fishing reel for winding up the wire.

The SuperRod lowered and the wire neatly wound up on the hand reel.

You could also wind it around any other kind of former, such as those designed to tidy up extension cables, but it is essential that the wire is not bent too sharply or kinked in the process, or erection and lowering of the antenna will be made more difficult.

3) Telescoping Sections

The smaller sections can drop down inside the larger ones and get jammed, also trapping the wire inside. This will require a complete disassembly of the antenna to disentangle. A simple solution is to fit a nylon string to the tip of the smallest section and to tie a ping-pong ball or similar sized plastic object (I use the top off a deodorant can) about 50cm from the tip. Then, none of the smaller sections can disappear very far inside the larger ones, and you can pull them out using the nylon string. A bead to hold the nylon string in place.
4) Preventing the Wire from Breaking or Pulling Out The wire jammed and broke (actually it pulled out of the top section) while I was experimenting with erecting the antenna. 9m of antenna is a bit of a handful to hold and I must have pulled too hard on the wire, and you certainly don’t want this to happen in a remote location. So I disassembled all 9 sections to get at the top section. The red insulated wire as supplied is joined to a fairly thin solid copper wire part way up the thinnest section, since the red wire is too thick to go through the centre hole in the fibreglass. The solid wire is pushed through the tip of the section and presumably glued or crimped in place, but not very securely. This is what failed so I discarded the thin copper wire. To improve this aspect I drilled a 1mm hole down the tip of the section, just deeper than the crimping band, and securely soldered a 50cm piece of thicker copper wire to the red insulated wire. Then I inserted it through the top section until it protruded from the tip. I soldered a round terminal to the wire sticking out of the end, to prevent it ever slipping inside the rod again. Bending a 6mm loop in the wire would work as well and either method will also provide a means of attaching a nylon string to the top section. A small bead was used to secure the string to the terminal so it all still nests together neatly. A bigger object was then attached to the string as mentioned above, to prevent any of the sections from sliding too far in. A terminal soldered to a thicker copper centre wire after drilling a 1mm hole in the tip.
In retrospect, I found disassembly of the antenna and replacing the wire to be a very useful exercise because I now know how to replace the wire if it ever breaks again while travelling. 5) Connection the Antenna to the Radio A PL259 socket (or whatever connector you need to match the one on your antenna lead) needs to be mounted near the bottom of the antenna for connecting the coax cable from the radio. You might need to extend the radio antenna lead if it no longer reaches the new bullbar mount. The centre connection of the socket can be fitted with a short wire with a male bullet connector crimped on, to connect to female bullet connector on the antenna wire. The ground (outer) section of the connector needs to be connected to the chassis of the vehicle using a ground cable which is as short as possible. The bull bar frame might be OK as long as that itself is well grounded to the vehicle chassis. Fit a ground cable from the socket to the vehicle chassis just in case. You can tell how effective the grounding is buy turning on the radio, with the antenna erected and connected, and listening to the level of background noise received. It will change in volume as the grounding is improved or made worse. Maximum noise volume (ie best match with the radio) indicates the improved grounding. This doesn’t take the place of proper antenna tuning and matching tests but unlike tapped whip antenna bases, the SuperRod has no matching components, only a centre wire, so some experimenting is necessary. With a tapped whip antenna mounted as well as the SuperRod, I was able to switch the radio lead from one to the other and confirmed that the SuperRod certainly had better reception (higher signal strength) on 8022 KHz than the tapped whip. As to be expected it also received background noise better as well. 6) Using the SuperRod on Channel 1 (5455 KHz) The 9m SuperRod can also be used directly on VKS737 Channel 1 on 5455 KHz, with some loss of performance since it’s not matched to the transmission frequency. It really should be 13.75m long to be a 1/4 wavelength at that frequency. Channel 1 performance can be improved by fitting a loading coil so it looks to the radio as if it were a 13.75m antenna, but they cost around $40-50 commercially, but one could be wound much more economically. I found that a simpler solution was to attach about 4.5m of additional wire between the radio antenna lead centre wire and the SuperRod wire connection and to droop this loosely over a nearby bush/tree branch. It will work better there than just lying on the ground, but keep people away from the wire when transmitting to avoid radiation burns. This is not as good as a tuned loading coil but is adequate as a fallback.
A better but more tricky alternative is to connect the extra wire to the top of the antenna, using the solder terminal fitted at the tip, and to extend that wire out sideways and/or upwards as far as possible, using a piece of nylon string attached to the end and fixed to a tree/bush etc. It will now be the correct length and nice and high, although the antenna will bend a fair bit and its radiation pattern won’t be optimum. Note that similar bent antennae, called Near Vertical Incidence Skywave (NVIS) systems, are available from Codan, Barrett etc, as in the sketch here. This system optimises the skywave signal path for short range communications (inside the normal skip distance) by directing some of the transmitted energy upwards at an angle, rather than horizontally, which reflects off the ionosphere to closer destinations. The Royal Flying Doctor Service (RFDS) uses frequencies in the 5 MHz range (5145, 5110, 5300, 5360, 5410 KHz depending on location of their bases) which are similar enough to the VKS737 Channel 1 frequency of 5455 KHz that the SuperRod with the additional 4.5m of wire should be capable of using them effectively. Some tuning of the exact length could be done as required using the formula (300/Frq MHz)/4. For Frq=5.3 MHz (5300 KHz), for example, an additional wire length of 4.8m would required.
See the RFDS frequency usage chart here. The wire I use is the type sold in hardware stores for use with low voltage garden lighting systems. I has a 10 amp current carrying capacity and nice thick insulation since it’s intended for outdoor applications, so it’s ideal for laying on the ground or throwing up trees. It’s usually twin conductor but is easily split into single conductors. 7) Power-Line and Lightning Warning
Be very aware of overhead power lines, see this recent sobering story.
Before raising a SuperRod, first look upwards to ensure there are no power-lines within range (which maybe only 6 m above ground level and well within the reach of a 9 m antenna), especially in populated areas such as caravan parks, national park camping areas, roadside rest areas or boat ramps. It’s too easy to just raise the antenna, section by section from bullbar level, without first checking upwards. You could get a very nasty (and fatal) surprise, and in any case, your radio won’t work very well in the proximity (~100m) of power lines due to the noise induced from the power transmission. Transmitting probably won’t be affected but reception certainly will. A tall antenna such as the 9m SuperRod will also be very attractive to lightning, so be very careful about using it when there are thunderstorms about. In particular, don’t rely on lightning protection devices and don’t leave it up at night if there is the slightest chance of strong winds or thunderstorms springing up unannounced.
Remember, in a thunderstorm you don’t want to be the tallest thing around.
References:

 

 

The WANSARC radio club has a useful review of the SuperRod on page 5 of this issue.