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Are we about to make yet another monumental mistake? Let’s face it: Australia has had some really dumb decisions over the years when it comes to communications. Like plonking VHF TV channels in the international FM Radio band many years ago. Like recently shutting off Radio Australia shortwave services so the bush has no viable alternative. Are we about to make yet another one with DAB+? What’s next for Australian Broadcast Radio? by ALAN HUGHES C urrently we have a mish-mash of broadcast radio services in Australia. Depending mainly on topography, the capital cities are relatively well-served with AM, FM and DAB+ Move to regional then to outback areas, the choice quickly reduces to less, to not much, to none at all. But Australians could have truly national radio services and countries such as New Zealand and Indonesia are showing the way with DRM – Digital Radio Mondiale. Currently we have AM, FM and DAB+ digital radio in all mainland State capitals, and AM and FM covering regional areas. But since 31st January this year, when the ABC in its wisdom switched off all shortwave broadcasts, there are no radio services for the 628,000 in the “outback”. Of course, you can listen to literally thousands of radio stations from all around the world, streaming via the mobile phone network or the internet. The former assumes you have mobile phone coverage – there are huge areas of Australia without it – and which costs you a significant amount of money. siliconchip.com.au Typical streaming radio consumes up to 60MB per hour, so depending on your plan, could gobble up your allowance in very short time. Alternatively, you can listen to some radio services (mainly ABC/SBS) in the home via VAST – Viewer Accessed Satellite Television – but you cannot watch TV and listen to radio at the same time. And this is obviously impractical for mobile (vehicle) listening. It hasn’t always been this way; until last January Radio Australia had 50kW shortwave transmitters in Katherine, Tennant Creek and Alice Springs and seven 100kW transmitters in Shepparton, although only three were in use. Now they are all switched off. The ABC claims to be using the money saved from switching off HF broadcasting (reported to be just $1.9 million a year) to pay for the extension of DAB+ transmitters. But even if this happens, the turn-off has left the outback areas without any viable radio service. AM, FM and DAB+ All told, there are 540 AM transmitters in Australia radiating from 50W to 50kW and almost 2,500 FM transmitters in Australia radiating from 1W to 250kW plus there are 73 standby transmitters. Each transmitter carries a single program with some transmitting Radio Data Service (RDS) for the display of a line of text. Some ABC transmitters are not fed with stereo sound, even though they might show a “stereo on” indication on the receiver. By contrast, each DAB+ transmitter carries between 15 – 26 programs. The ABC is transmitting 11 programs and SBS eight programs. All DAB+ sites have three 50 kW(erp) transmitters except Adelaide and Perth which have two each. In addition there are 37 on-channel repeaters. Mobile broadband streaming through the mobile phone network of cellular transceivers is being promoted particularly by AM broadcasters. But while this may work (at a cost) in more populated areas, this is not a solution for remote areas since mobile phone coverage is sporadic, at best. Satellite phones are available but their operating costs are very high compared to cellular (mobile) phones. To cover the bush, a huge number of uneconomic mobile phone transmitters would be required – and unlike a broadcast radio receiver, the phone network must track the movement of September 2017  61 the phone through the network, which drains the phone battery. So currently there is no effective radio coverage for the outback. At the time of writing, a bill is before the Senate to force the ABC to resume shortwave transmissions, but there is no guarantee of success. Does AM/FM radio even have a future? If you live in the major cities or regional areas, you may not care about radio in the outback. But it is possible, even probable, that we may not always have AM and FM in our cities – and that might happen sooner than you may think. The future may mean DAB+ only in the cities and not much in the regions. You might scoff but look at the trends. Currently there are 3.8 million people able to access DAB+ stations out of a licence area covering 14.8 million people. There are also 826,000 vehicles which have DAB+ radios, compared with a total of 10.4 million vehicles. In 2016 more than 33% of new passenger vehicle sales were fitted with DAB+ radios, a huge rise, which will continue because of the widespread adoption of DAB+ in Europe. Many of the AM radio transmitters in Europe (and even many FM) have been permanently switched off. Take Norway, for example: by the end of this year they will have switched off their remaining FM transmitters, leaving only DAB+ radio. 99.5% of the Norwegian population have access to DAB+ and 98% of new vehicles sold there have DAB+ radios factory fitted (DAB+ adaptors are available for older cars). Back here in Australia, receivers for AM radio are becoming harder to buy. As a result in a trip to a major chain store, I found only one receiver/ AV system which would receive AM. Most are either DAB+/FM or FM only. The same applies to receivers available on line – they’re cheaper to make because they don’t have AM. The AM broadcasters can see this trend even if the listeners are unaware. DAB+ expansion Next year, DAB+ broadcasting will start in the regions, as shown in Table 1. One would expect the largest populations would be the first to receive their new transmissions. This matches 62  Silicon Chip Area Population Dwellings/ Ch Power ea (000s) Vehicles (000s) (kWerp) Gold Coast 570 465 9D, 8B 5# Newcastle/Lower Hunter 518 417 Sunshine Coast 347 298 Central Coast 328 260 Illawarra 293 216 Geelong 279 238 Canberra/Queanbeyan 253 198 8D, 9C 5 Cairns 240 186 Townsville 229 181 Hobart 222 168 9A, 9C 20 Darwin 137 105 9A, 9C 20 Data sourced from the 2016 Census. # with possibly 3 repeaters Table 1: planned expansion during 2018 of DAB+ services to major regional population centres. However, with limited transmitter power, the coverage area will also be limited. the multi-broadcaster capability of DAB+ but also has the smallest coverage area of the options available. Some regional areas will be restricted to one transmitter to carry maximum of four commercial broadcasters, two community broadcasters, ABC local Radio and two high-power open network broadcasts such as the TAB, religious and particular language broadcasts. With a capacity of nine broadcasters for each transmitter, there will be unused capacity. Major areas may have a second transmitter, which will carry all other ABC/SBS programs using a single frequency network. This means that the transmitter and all those geographically adjacent to it must use the same channel and have identical programs at the same time. This will cause the ABC problems near state borders, as news bulletins are different. In addition on the NSW/Qld and Vic/SA borders, the time zone changes will result in channel 9C being used on one side of the border and channel 8B on the other. But this has major drawbacks because the proposed DAB+ transmitters are mostly 5kW – and this would mean that their coverage is even less than existing FM transmitters, so that is not going to extend radio coverage in regional or outback areas. DAB+ was initially designed for Europe, which has 500 million people spread over an area of 10 million square kilometres compared to Australia with 24 million people spread over 7.7 million km2. Currently the planning is to use low power DAB+ which will produce an effect like mobile broadband coverage. Both need for large numbers of low powered transmitters which produces an uneven “spotty” coverage. This is mainly caused by the approximately 200MHz transmission frequency of DAB+ and the coverage will be smaller than for the present FM broadcasts (which transmit around 100MHz). DRM: the solution for covering low population density It’s not something that many people have even heard about in Australia but the only real solution is Digital Radio Mondiale Plus (DRM+). This is basically long-distance digital radio, designed to cover large areas at much lower cost than DAB+. Rather than the eight DAB+ channels, there are 119 transmission channels available between 56 – 68MHz (the old analog TV channels 1 and 2). Because their frequency is around a quarter of that used for DAB+, these signals have very much wider coverage and penetrate buildings better. A DRM+ channel could carry ABC local radio at its present 64kbit/s and the pair of current commercial programs at 48kbit/s each, which is common practice, leaving 26kbit/s for pictures and text. The transmitter could be located at the current commercial broadcasters’ FM transmitter site which is close to their audience. So how does DRM work? Jim Rowe SC explains it opposite . . . siliconchip.com.au