Many thanks to SWLing Post contributor, Nigel Holmes––formerly of Radio Australia––for the following op ed.
The Shepparton transmitter site of ABC/Radio Australia
Developments in the Australian domestic HF broadcasting scene
by Nigel Holmes
Radio broadcast on HF (high frequency or shortwave) has a solid role to play in the pantheon of media in the Australian and pan-Pacific context. It might be off the radar for the urban masses, but HF radio is the proven, economical alternative to satellite and cable for communication over continental or oceanic distances. Our commercial airlines use HF radio every day. So do our mining companies and emergency services. People holidaying in our remote areas buy or rent HF transceivers for their cars. Australia has the largest number of civilian users of HF radio in the world.
For thirty years a simple system of three HF transmitters quietly provided Australian Broadcasting Corporation (ABC) radio to remote populations across inland Australia, the Northern Territory (NT). Centered on Alice Springs, Tennant Creek and Katherine each transmitter reached out nominally 450 km, covering an area of nearly 2 million square kilometres. In practice the area serviced was larger, extending into Queensland and Western Australia. Such is the utility of this versatile medium. The audience was small, only a couple of hundred thousand, living or moving through the most remote places in Australia, but this was their lifeline.
During the cyclone season, storm alerts and flood warnings would reach people in the inland beyond the call of AM and FM networks. Yes, such people do exist in Australia and elsewhere in the Pacific.
Like many marginalised communities the HF radio listeners of the outback struggled to make urban elites understand their very real world. So in 2016 when the ABC announced the closure of the domestic HF transmitters in order to fund its DAB+ radio rollout in Canberra and Hobart, the backlash from the remote communities was shrugged off and the closures proceeded in 2017. ABC pointed at its satellite as an alternative, but had no answer when asked how to equip a jillaroo’s horse, a dusty 4WD or an offshore tinnie with a fragile satellite dish, an expensive receiver and the power point to run it all.
People who are used to an effective service tend to take its loss badly. So it has been in the NT. Politicians were pursued by the inland listeners wanting a better deal. The matter has culminated with the main opposition Australian Labor Party pledging to restore the HF distribution of ABC within Australia if it wins the forthcoming the federal election.
Let’s hope political expediency at the federal government level and within ABC doesn’t foul this up. We don’t want a half-baked resurrection as a sop to fend off critics of the ABC or to let politicians grandstand.
The three domestic HF sites in the NT cost a lot more than AUD$1.9 million p.a. to run. That was a figure bandied about by ABC after criticism of its DAB+ expansion costs. But for a sum in the order of half that, plus re-establishment costs, a service can be implemented which would have greater coverage, better reliability and lower outgoings. What’s not to like? The key is the former Radio Australia HF station at Shepparton, Victoria.
The cost of electricity at the NT sites was horrendous. Apart from feeding three thirsty 50 kW tx, huge air conditioning plant was required at each site to pull out waste heat and combat 50°C summer temperatures. Maintenance costs were savage. On-air availability was lousy (worst in the ABC network) because of environmental challenges and long maintenance travel times.
So here’s a plan: re-locate a near-new Continental 418G HF 100 kW transmitter from Tennant Creek to Shepparton. Electricity is much cheaper and more reliable at Shepparton. It’s a cooler site and has permanent, trained staff. The consolidation of spares and expertise with the other Continental transmitters at Shepparton makes engineering and economic sense. Re-locate the two small 6-12 MHz HR2/2/0.4 and HR2/2/0.6 aerials from the former RA station at Brandon. Erect them both as AHR2/2/0.4, align one on a boresight of 000°T and the other one on a boresight of 320°T. Feed both aerials from the transmitter via a splitter, run the transmitter at 80 kW so each array receives 40 kW. Run a 5.9 MHz channel at night and a 9 or 11 MHz channel during daylight. Bingo. You now have a two-frequency network covering the sector between 020° & 300° at a range of 1500 km -> 3000+ km. What a great conduit for cyclone/flood alerts, quality news and entertainment and if the ABC can manage that then it might just get back to meeting its charter obligations to all Australians.
Nigel Holmes
November 2018
Sorry for the double post, my very slow internet is the problem. It has also omitted my original post.
Nigel,
I should add the following.
The latest census shows that there is 600,000 people who live in remote Australia. Whilst many of these people can receive radio whilst at home from VAST or a town transmitter. However, when they leave home or town driving riding or boating there is no radio at all,
The ABC also closed the 50 kW HF Pilbara and the 50 kW HF Kimberley services in January 1994. Just like the NT, use the time when the population is least due to the monsoon and parliament is in recess. The WA services came from Hamersley (Perth), Qld from Brisbane, Shepparton and even VLI in Sydney for NSW Central Coast/Illawarra.
The Broadcast Australia has deleted the Katherine and Tennant Creek HF sites from their site finder.
The is no mention of the 11 year old Tennant Creek and one of the Shepparton transmitters are DRM capable. When in the DRM mode is used the electricity consumption drops by 67 % and the electricity used by the cooling is less as well. In addition it could also transmit the Emergency Warning System. This means that in the event of a cyclone, bushfire, flood, the radio will wake up, increase the volume, display a map of the affected area and has instructions on the blocked roads in text etc.
I should also mention that all Darwin (137,00 people) radio including the new DAB+ and TV is radiated from the same tower. This could be blown down in another Cyclone Tracy. There is only a 2 kW MF AM Radio National transmitter in Ludmilla which is close to the coast and has a very low altitude so could be subject to storm surge or tsunami.
I should add that the dismissed ABC CEO claimed that remote listeners could listen to broadcasts on their phones. The coverage area of mobile (cell) phones is a radius of around 10 km from those villages who have them. This is the same coverage area provided by the VAST fed low powered FM transmitters.
The ABC did not acknowledge that satellite phones are $Au 3.00 per minute and cannot stream data. They also don’t work in heavy rain or within vehicles unless an external antenna is used. This is why there is two manufacturers of HF two way radios in Australia which will work in these conditions. These two way radios can dial phone numbers and could receive the discontinued ABC broadcasts.
I should add the dismissed ABC CEO claimed that remote listeners could listen to podcasts (which are not live!) and streaming. The mobile (cell) phone coverage is a radius of 10 km from a tower and with the exception of Darwin, Alice Springs, the coverage area of low power VAST feed low powered FM transmitters is the same coverage area.
Satellite phones cost $Au 3.00 minute, cannot stream data and will not work in heavy rain was not acknowledged by ABC management.
NIgel,
I would like to add the following;
The latest Australian Bureau of Statistics census shows 600,000 people living in remote Australia. Whilst many of these people can listen to the radio in towns and villages or at home on VAST they cannot get any radio outside of those location whilst driving or boating.
You have concentrated on the NT coverage. On 24th Jan 1994 the ABC closed the 50 kW Pilbara and 50 kW Kimberley HF services from Hamersley, on the site of 50 kW Local Radio, 25 kW Radio National and 10 kW Newsradio. http://watvhistory.com/2012/08/the-6wf-story-part-2-of-3/ . Program content consisted of a mix of Regional radio and Radio National. Even earlier HF broadcasts also came from Brisbane, Shepparton and even VLI which was for the NSW central coast and the Illawarra.
So why should residents, tourists and itinerant workers in WA, SA, Qld, West Tas, Western NSW should miss out? Instead of NT only coverage the transmitter network should be changed to national coverage.
https://www.acma.gov.au/Citizen/TV-Radio/Television/Lists-of-broadcasters/list-of-licensed-broadcasting-transmitters lists all TV and radio broadcast transmitters except HF transmitters but including DAB+ digital radio.
The NT HF transmitters are using frequencies just above the MF band, where as long distance reception uses higher frequencies and these were used for the Pilbara and Kimberley from Perth.
You also have not mentioned the Tennant Creek transmitter along with one at Shepparton are DRM capable. When operating in this mode the electricity consumption by the transmitter drops by 65 % let alone the drop in electricity by the air conditioning. DRM is also capable of transmitting the Emergency Warning System which will wake up a radio, increase the volume, show maps of the cyclone/bush fire/flood warnings along with text instructions on road closures etc. In non emergency times, the news feed on the ABC website could be transmitted including the pictures.
I notice that the Broadcast Australia Site finder no longer lists the Katherine and Tennant Creek HF sites. Roe Creek and Shepparton HF are still there.
Lastly, all radio including DAB+ and TV in Darwin is radiated from the same tower, so if Cyclone Tracy was to be repeated, there will be no warnings. The only exception is Radio National AM at Ludmilla which is close to the coast and almost at sea level. Cyclones generally produces a storm surge.
So typical to look to shut down a vital HF service in favour of DAB for the townies when they already probably have high speed internet through which they could stream broadcast stations. Nigel has presented a viable solution which I can only hope is seriously considered by the powers that be.
Any one who cares to learn about the dispersion of MF & VHF radio broadcast transmitters (commercial, community & national broadcaster) across Australia can find details here:
https://www.radioinfo.com.au/am-radio-stations-australia
https://www.radioinfo.com.au/fm-radio-stations-australia
Put it on full screen, drag & zoom in as required & click on a site to retrieve technical details.
Note low power of the FM services in the NT – 0.2 W – 100 W into masts 10-20 m agl hence the limited range confined to the small communities. Note that MF is next to useless in the NT – 100 W – 1 kW into ~ 30 m – 100 m masts & using low freqs.
Laurence: Follow the link “within Australia” Read & listen. Then read the submissions to the Senate review held last year.
ABC has privately admitted to me it was stunned by the strength & range of critical responses received after closing the HF services. ABC did no on-the-ground surveys prior to making the decision, but it did intentionally degrade the services by wilful frequency management of several transmitters, e.g. running the “day” frequency (4835 kHz) from Roe Ck 24/7 which put a 400 km hole in the target area at night (and put a massive signal in to Melbourne & Sydney 2000 km away…)
Your guess on MF & VHF coverage is … wrong. NT is huge, QLD & WA are larger. The notion of Mum & Dad small MF tx doesn’t work there. Small MF tx typically have shorter radiators which means poorer night reception within ranges 50-200 km due to destructive interference between groundwave and skywave propagation. No one is going to fund 190° anti-fade radiators for several dozen 5 kW MF tx which is what you would require to cover NT. In Australia the highest powered MF services are allowed 50 kW carrier – the same as the domestic HF tx, with the exactly the same problems of electricity costs, air con. costs & remote area maintenance, but with the disadvantage of a range of only 250 km if equipped with that massive anti-fade radiator. In short a lousy alternative to HF. In any case MF reception in the “Top End” is badly impacted for six months of the year by static crashes from millions of lightning strikes generated by the thousands of tropical storms that roll continuously through the tropics.
VHF coverage is a joke for remote area coverage – a radial coverage of maybe 40-50 km per site, a nightmare of maintenance issues, reliance on mains power which is severely limited in distribution or on solar PV which is more expensive (& attractive to the light-fingered brigade), in short a capital investment black hole. VHF does avoid the tropical noise problem and works for a population centre > 1000 and guess what? – those towns have got it already.
I’ve been listening to cricket and rugby every summer since I was a kid – and still don’t know the rules. But its s a fun thing to tune into a later summer evening or early morning!
This has become a major problem for swling post readers, it seems. I don’t get it. I did enjoy picking up ABC on shortwave once in a while, although reception is really hard where I am, but I think it’s important to realize that none of us are being targeted by ABC’s operation. So perhaps we should ask to what extent these HF transmissions were being used by those who were actually the audience in mind at the ABC headquarters. The first question I’d have is how many people in Australia itself used those to receive their ABC content; there are a lot of AM transmitters there that cover wide areas and are more stable, and the availability of satellite equipment has been rather comprehensive. So what parts are not covered by those? We know that satellite is available everywhere, but I’ll admit that it doesn’t work so well on mobile vehicles. But how much of Australia lacks an available AM or FM transmitter? I would guess that it’s not a ton of it. Wouldn’t it be more efficient just to install another one of those to cover any dead spots?
Now for the international radio use in the Pacific. We would have to go to those islands and ask the people what they do to get news. Simply pointing out that they could have been using ABC’s shortwave service is not enough; if they did not use it, or if they listen to ABC through other means, then the ABC would be entirely justified in dropping it. I do not see this covered here in the many articles posted by people seemingly nostalgic for a large quantity of broadcasters on the bands. People talk about emergency coverage and international use as if these were already fully proven assertions. Until I see something to contest the ABC’s request for complaint that did not receive very much at all, I cannot be bothered to care that Australia has shut down their equipment.
Fascinating solution, Nigel. Weaning people from dependency is often difficult whether drugs or some other service. Much forethought needs to be given to such matters BEFORE acting which apparently ABC didn’t do. I’m sure an equitable solution such as your proposal can be found by Australians for Australians while concomitantly reducing costs.