FutureWave Energy Saver gave a major project saving
I would like to offer a comment on the suggestion of using the MEMS accelerometer for measuring “aircraft bank”, raised by Pete Mundy in the Mailbag pages of the September 2011 issue.
Some years ago, I was working on the Flightship ground-effect vehicle project in Cairns and we were trying to find a cost-effective solution to measure what we termed “pitch and roll”. MEMS accelerometers were a bit new then but we thought it was worth a try.
At its cruising speed of around 75 knots we found that when making a turn, the craft would roll to about 15°. At this angle, as far as the accelerometer was concerned, it was still perfectly level and if it was not for seeing the horizon the occupants thought so too. So how did we determine we were in fact at 15°? We spent $10,000 on a vertical gyro, which at that time was the only thing that could deal with the problem.
I would also like to comment on the Future Wave Energy Saver. We recently finished installing a large hydroponics system in a building on the Sunshine Coast. It features 22kW of LED lighting, which is another story, but it also used a pair of large pool pumps running in tandem to circulate nutrient. The problem was that one pump was a bit small and two was too much and caused considerable cavitation.
I happened to read the FutureWave review in the June 2011 issue of SILICON CHIP a couple of weeks earlier and the project owner contacted them. They had the prototype dual-pump version on hand and attended the site to make a temporary connection for evaluation. A couple of small adjustments and the pumps worked perfectly and we were even saving about 30% of the running cost.
The normal cure would have been to install a large 3-phase pump and a VSD, so FutureWave saved us far more than the cost of their product.
Gary Smith,Montrose, Tas.
DAB+ is not the same as DAB in the UK
I am writing regarding the Mailbag letter from Kevin Poulter, Dingley, Vic in the September 2011 issue of SILICON CHIP, featured and highlighted with the heading “Digital radio – the future or just a pipe dream?”
It’s hard to know where to start with so much misinformation in one letter. Let me try and correct the glaring errors. Firstly, attempting to link digital radio research in the UK with what is happening with digital radio in Australia is misguided. Digital radio in the UK uses the less spectrum efficient DAB standard, has no slide show capability, is based on a completely different business model, and has only in the last two years implemented an all of industry approach to awareness and marketing.
Mr Poulter writes, “Commercial Radio Australia is claiming that over 500,000 digital radios have been sold since the service was launched two years ago”. Commercial Radio Australia (CRA) is not claiming it, digital radio sales are compiled in the GFK Marketscope report where data is collected directly from retailers. The actual number of digital radios is in fact even higher, as the GFK figure doesn’t include all categories, all retailers or all online sales.
There is no switch-off date of analogue AM and FM radio services in Australia. Mr Poulter is wrong and is using a 2015 target from the UK, which has no relevance to Australia. Although digital radio is available in Sydney, Melbourne, Brisbane, Adelaide and Perth and covers nearly 60% of the population, the service is not yet available to all Australians. The industry is working with the Federal Government on planning for the roll out of DAB+ digital radio for regional areas.
Again, Mr Poulter writes incorrectly “. . . digital radio has dipped into our taxpayer’s money with little result”. The metropolitan commercial radio broadcasters have funded the transmission infrastructure for digital radio. As professional broadcasters they believe this is the radio of the future and that it offers their listeners a chance to experience new content and digital quality sound.
Another sweeping unsubstantiated comment by your reader is, “Portable receivers with almost no exceptions are expensive and can only be heard in mono from an atrocious tiny speaker”.
There are more than 100 different DAB+ digital radio models available to purchase in Australia, starting in price from as low as $49. Manufacturers recognise that not everyone wants high-end products that have pause and rewind, pictures, stereo, Wi-Fi and iPod docks and have produced a range of portable, kitchen-top, personal, hifi, clock radio and adaptors that listeners can choose from.
But the most inaccurate information in Mr Poulter’s letter is this statement, “Then there are the reception problems. You can listen to AM radio station 3AW right into Gippsland (country Victoria) but not DAB+. 3AW AM consistently wins the ratings”.
Your reader is obviously unaware that radio broadcasters are licenced in a specific licence area. 3AW is licensed to broadcast in the Melbourne metropolitan area only. Analogue AM/FM and DAB+ digital radio may in some instances broadcast outside the licence area in what we call “overspill” but the broadcast is not designed or licenced to broadcast outside the licence area.
The reason digital radio is not heard in country Victoria is not a reception issue because there are no digital radio broadcasts in country areas yet. As previously mentioned, the industry is working together with the Federal Government on spectrum planning, to enable all Australians to try digital radio.
It’s really disappointing when inaccurate information is printed, whether it’s in a letter to the editor or in a story. I would appreciate you publishing my response in full to ensure your SILICON CHIP readers and Mr Poulter have the correct information about digital radio in Australia.
Joan Warner,Chief Executive Officer,Commercial Radio Australia.
Kevin Poulter replies: No doubt some of Ms Warner’s comments are correct, however rather than a long exchange of views, here are the relevant points that affect most SILICON CHIP readers. Ms Warner says “There is no switch-off date of analogue AM and FM radio services in Australia” but was quoted in a recent article in “The Age” as saying that eventually there would be a mandatory switch-over: “Our view is that there would have to be 80 percent or upwards of listening to DAB+ for the industry to agree to switch off analogue. My personal view is that getting to 80 percent will take another five to seven years”. Further – “That’s 50 million radios that need replacing”.
No plans to oust AM? I do have a very recent article that states, quote “The federal government has been a keen supporter of the (digital radio) industry as it seeks to switch analogue users over to digital, in a bid to free up radio spectrum for auction”. This would be a red flag to the millions who own multiple AM radio sets in their home and car, especially as it appears to be the intention in the UK.
Choice said earlier in the year that “you’d be better off buying an analogue radio for a fraction of the price” (see the Choice website for much more). In, Melbourne, “The Age” ran a feature: “Listeners give digital radio a poor reception”, by Stephen Cauchi on September 4, 2011. See: http://www.theage.com.au/technology/technology-news/listeners-give-digital-radio-a-poor-reception-20110903-1jrcg.html
Nearly every digital radio has a tiny speaker, even those priced up to $700. They just don’t deliver the digital quality. I can purchase a superb secondhand Panasonic or other leading brand AM/FM transistor radio or cassette portable radio for $20-$80 and the big speakers deliver excellent sound. Car audio manufacturers expected great things from DAB+ but soon found patchy reception.
I also received comments from other readers, however they are too close to the industry to add their names to this discussion. For example: “I share your concerns regarding the poor audio quality of DAB+; this is a deliberate choice where multi-channel has been chosen above audio fidelity. Unfortunately the younger generation are used to low-fidelity digital audio and know no better”!
One big plus for DAB+ is that it is “green” technology. One 5kW DAB+ transmitter transmits the ABC/SBS ensemble from Mt Dandenong. Compare this to the 50kW output from each of the two AM stations on 621kHz and 774kHz!
The best thing that can be done for consumers is for manufacturers to install bigger speakers. I wish digital radio well but not at the expense of AM.