Fullscreen HTML5Med Res (??MB)HTML4

Publisher & Editor-in-Chief Leo Simpson, B.Bus., FAICD Editor Greg Swain, B.Sc.(Hons.) Technical Staff John Clarke, B.E.(Elec.) Robert Flynn Rick Walters Reader Services Ann Jenkinson Advertising Manager Brendon Sheridan Phone (03) 9720 9198 Mobile 0416 009 217 Regular Contributors Brendan Akhurst Garry Cratt, VK2YBX Julian Edgar, Dip.T.(Sec.), B.Ed John Hill Mike Sheriff, B.Sc, VK2YFK Ross Tester Philip Watson, MIREE, VK2ZPW Bob Young Photography Glenn A. Keep SILICON CHIP is published 12 times a year by Silicon Chip Publications Pty Ltd. A.C.N. 003 205 490. All material copyright ©. No part of this publication may be reproduced without the written consent of the publisher. Printing: Macquarie Print, Dubbo, NSW. Distribution: Network Distribution Company. Subscription rates: $54 per year in Australia. For overseas rates, see the subscription page in this issue. Editorial & advertising offices: Unit 34, 1-3 Jubilee Avenue, Warrie­ wood, NSW 2102. Postal address: PO Box 139, Collaroy Beach, NSW 2097. Phone (02) 9979 5644. Fax (02) 9979 6503. PUBLISHER'S LETTER Backing up is not hard to do These days most of us have a computer or have access to a computer and so most people are familiar with the concept of backing up their work. The reasons for doing so are plain common­sense. If you do have a computer failure and you have religiously backed up your files, then you won’t have lost a lot of work. I’m not just thinking about people in business in raising this topic. Many people with computers in their homes use them for quite crucial aspects of their lives. Students use them for writing essay assignments, for keeping track of research work and for writing theses. For an undergraduate to lose most or all of a thesis would be traumatic indeed. Similarly, people might use their computer for club records, for their medical records, financial records, share dealings, hobbies and so on. In every case, the loss of all this information can happen so quickly, in the blink of an eye so to speak, that the event can be emotionally shattering. And finan­cially shattering as well. And since hard discs are becoming larger all the time, the size of the potential data loss is also growing, at an exponential rate. Just recently, one of the machines in the SILICON CHIP office had such an event. One moment the machine was working perfectly normally, as it always had since the day it was pur­chased. The next moment, there was a screen message to say that one of the 1.6GB discs was unreadable. Just like that! As it happened, we were just about to replace that particu­lar disc drive with one of 3.2 gigabytes so the physical loss of the drive was of no particular concern. It turned out not be damaged anyway. But what about the files? Well, running CHKDSK produced many hundreds of files which all had to be renamed and then imported to be checked. Many were OK but some were not. The upshot was that we lost several days of work on this machine. All of this was in spite of the fact that we have backup procedures in place, whereby all working files are copied to the server every day and all those files are then backed up onto a DAT drive. Its capacity is 8GB. In theory, all we should ever lose, even if the server and all our computers were stolen or destroyed in a fire, would be one day’s work. But in practice, who knows? In fact, this one machine and the server’s drives were so full that the backup procedure had become a little loose. We could have lost a lot more work. We often hear of much worse cases, where people have not backed up anything for weeks, months or maybe never. Sooner or later, those people will suffer the consequences. Leo Simpson ISSN 1030-2662 WARNING! SILICON CHIP magazine regularly describes projects which employ a mains power supply or produce high voltage. All such projects should be considered dangerous or even lethal if not used safely. Readers are warned that high voltage wiring should be carried out according to the instructions in the articles. When working on these projects use extreme care to ensure that you do not accidentally come into contact with mains AC voltages or high voltage DC. If you are not confident about working with projects employing mains voltages or other high voltages, you are advised not to attempt work on them. Silicon Chip Publications Pty Ltd disclaims any liability for damages should anyone be killed or injured while working on a project or circuit described in any issue of SILICON CHIP magazine. Devices or circuits described in SILICON CHIP may be covered by patents. SILICON CHIP disclaims any liability for the infringement of such patents by the manufacturing or selling of any such equipment. SILICON CHIP also disclaims any liability for projects which are used in such a way as to infringe relevant government regulations and by-laws. Advertisers are warned that they are responsible for the content of all advertisements and that they must conform to the Trade Practices Act 1974 or as subsequently amended and to any governmental regulations which are applicable. 2  Silicon Chip