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  SILICON CHIP www.siliconchip.com.au Publisher & Editor-in-Chief Leo Simpson, B.Bus., FAICD Production Manager Greg Swain, B.Sc. (Hons.) Technical Editor John Clarke, B.E.(Elec.) Technical Staff Ross Tester Jim Rowe, B.A., B.Sc Mauro Grassi, B.Sc. (Hons), Ph.D Nicholas Vinen Photography Ross Tester Reader Services Ann Morris Advertising Enquiries Glyn Smith Phone (02) 9939 3295 Mobile 0431 792 293 glyn<at>siliconchip.com.au Regular Contributors Brendan Akhurst Rodney Champness, VK3UG Kevin Poulter Stan Swan SILICON CHIP is published 12 times a year by Silicon Chip Publications Pty Ltd. ACN 003 205 490. ABN 49 003 205 490. All material is copyright ©. No part of this publication may be reproduced without the written consent of the publisher. Printing: Hannanprint, Noble Park, Victoria. Distribution: Network Distribution Company. Subscription rates: $97.50 per year in Australia. For overseas rates, see the order form in this issue. Editorial office: Unit 1, 234 Harbord Rd, Brookvale, NSW 2100. Postal address: PO Box 139, Collaroy Beach, NSW 2097. Phone (02) 9939 3295. Fax (02) 9939 2648. E-mail: silicon<at>siliconchip.com.au ISSN 1030-2662 Recommended and maximum price only. 2  Silicon Chip Publisher’s Letter Power factor correction gizmos do not save power The first week of February caused a certain amount of excitement in the SILICON CHIP offices. This was triggered off by the Seven Network’s Today Tonight feature item on the Earthwise Power Saver on Monday January 31st. This was immediately followed by a number of emails from concerned readers, suggesting that we do a thorough debunking of this product as we had with other power factor correctors (SILICON CHIP, November 2007 & May 2008). However, I had not had a chance to respond to those emails when I was approached by Today Tonight for an interview on the topic. Apparently, a number of viewers had phoned the station to state that the product was “a load of rubbish” (or words to that effect) and that Seven should contact SILICON CHIP to find out the real story. “Would you mind doing an interview on the topic?” asked the Channel Seven researcher. How could I say “No’? And thanks to those readers for making the suggestion. Today Tonight immediately sent out a crew and I prepared a demo to show what the product was supposed to do and how it could not save consumers money. The interview was done in great haste, with reporter Rodney Lohse in Brisbane via mobile phone while I was in our editorial offices. Being asked not to look at the camera but at a point on a bookshelf (to simulate talking to the interviewer) was distinctly odd, I can tell you. As it turned out, probably due to programming constraints, Today Tonight did not run the whole interview but I was glad to get across the message that any device based on power factor correction could not save power and would result in no saving for the consumer. You can read the transcript at: http:// au.todaytonight.yahoo.com/article/8756894/consumer/power-saving-ideas The matter did not end there though because Channel Nine’s A Current Affair had run a segment on a very similar product on the same night as Today Tonight’s feature item. They also had received trenchant criticism from viewers and presumably, having seen my debunking of the concept on Tuesday, 2nd February, had decided to investigate further. They then asked the promoter to run through the demo again but this time showing readings in watts (power) rather than amps (current). This time the result was very different and the promoter was depicted in his self-induced destruction. Having obtained such a damaging video, reporter Damian Murphy also visited our offices for an interview and a somewhat more detailed demonstration of power factor correction. This was supposed to go to air on Friday, February 6th but again, extended reporting on the aftermath of Cyclone Yasi meant that it was not featured. They duly apologised. However, A Current Affair did include a brief quote from an Emeritus Professor of Electrical Engineering and his words effectively administered the coup-de-grace to the product concept. Well done. Several concerns still remain though. For example, on the Earthwise Power Savers’s site it is possible to read an “independent report” which endorses the Powersaver product: http://www.earthwisepowersavers.com.au/public/pdf/ INDEPENDENT.pdf It compares the energy consumption at different times of the year and makes no attempt to show differences with the device switched in or out. As such, the report is simply invalid. Secondly, promoters of these sorts of products make outrageous claims about the quality of the electrical supply to homes. On the Earthwise Power Saver site you can see such drivel as: “up to 30% of the billable electricity consumed in homes and businesses is non-productive and unusable. What this means is continued on page 111 siliconchip.com.au Battery Packs & Chargers Siomar Battery Engineering www.batterybook.com Phone (08) 9302 5444 Issues Getting Dog-Eared? Keep your copies safe with these handy binders Price: $A14.95 plus $10.00 p&p per order (includes GST). Buy five & get them postage free! Just fill in and mail the handy order form in this issue; or fax (02) 9939 2648; or phone (02) 9939 3295 and quote your credit card number. Available in Australia only. South Croydon, Melbourne. Phone (03) 9723 3860. sales<at>electronicworld. com.au PRODUCT IDEAS WANTED: we are a distributor of automotive electrical accessories and are currently looking for new items to add to our range of Australian-made products. We are interested in products at all stages of development; whether an idea, partially or fully developed. We can provide assistance and funding for development and testing of suitable products. If you have a product which you think may be suitable, please send information to auto_elec_ideas<at>bigpond. com All enquiries and submissions will be treated confidentially. All enquiries will receive a reply. siliconchip.com.au Publisher’s Letter – continued from page 2 that even though you pay for all of your energy, you only use around 70% of it. This un-used, non-productive energy wastes money and also shortens the life of inductive equipment such as motors, HVAC equipment, pumps, and major appliances”. The energy retailers would rightly be peeved at this because firstly, the claims are rubbish and second, they are conscientious in ensuring that the harmonic content of the mains waveform is kept below defined limits. Nor can the installation of capacitors do anything to clean up the mains waveform. Thirdly, the energy retailers might also be very concerned with the concept of installing large capacitors across the consumer mains supply. Such capacitors could cause undue loading on their tone signalling systems. In fact, I would not be surprised that if they found it was a problem, they would immediately disconnect the offending premises until said capacitors were removed at the owners’ expense. As I said on the Today Tonight segment, “There are no easy ways to save power”. If there were, we would be doing it. Leo Simpson Ask SILICON CHIP – continued from page 107 remove the main board from the case to do the latter but I think it’s best to rule out these joints as possible problems before doing anything like removing the radio module shield. Editor’s note: feedback from the reader has confirmed that the fault was in the pins on the Venice 7 module. Confusion between Dolby Digital and DTS Recently, I dusted off my Denon DVD 3300 player and connected it to my hifi system and tried to play DTS and Dolby Digital at the same time. I noticed that on the disc menus it has them separate. I was hoping to have both DTS and Dolby Digital on the player’s display at the same time but this doesn’t seem possible. Why? The Denon DVD 3300 player was reviewed as a player for the audio­ phile and it was very pricey at the time I bought it. It is still much better than most medium-priced players of today. With the Denon player, Dolby Digital sounds much better than DTS; more hifi. Is it possible to purchase a DVD these days so that DTS and Dolby Digital can be played at the same time or is Dolby Digital separate for those who don’t have DTS? (D. S., via email). •  DTS (formerly Digital Theater Systems) and Dolby Digital are two competing and incompatible surround sound systems. It is not possible to have both systems operating simultaneously, even if a DVD was encoded with both systems. There’s a lot more information on this topic on Wikipedia. iPod feed for 12V amplifier I run a 12V bus in my house and am interested in the 12V Stereo Amplifier described in May 2010. Would it be possible to adapt the project so that it would accept an input from an iPod or equivalent? Modern car radios have such a facility as a Line input. (I. C., Longwood East, Vic). •  To connect an iPod to the 12V Stereo Amplifier you need a cable with a stereo 3.5mm phono plug on one end and two RCA plugs on the other. You also need a 10kΩ resistor to ground for each channel, to provide a DC load. The phono plug goes into your iPod’s headphone output, while the RCA plugs go into the corresponding input sockets on the amplifier. SC March 2011  111