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ELECTRONICS ON THE There’s a wealth of information on the Internet for electronics designers and engineers. You can check data sheets on the latest devices, order parts or even market your products via the World Wide Web. By SAMMY ISREB Before you turn the page thinking that this is just another Internet article WAIT! It has no resemblance to the myriad of articles on how to get onto the Internet and use it. In fact, before you can use any of the information in this article you have to be already “hooked up” to the Internet and be familiar with its use. So now that we know what this article is not about it is time to explain what it is about. The Internet contains hundreds of web sites and news groups that are dedicated to electronics. The news groups are made up chiefly of support or help groups, while the web sites are usually commercially orientated. Web sites Fig.1: the National Semiconductor homepage screen. Among other things, it allows the user to search for a component by part number, to browse a library of datasheets and to seek out technical advice and sales information. 4  Silicon Chip Many electronic companies have embraced the World Wide Web with open arms, setting up their own home pages. The most valu­able web sites for designing circuits are those of the IC manufac­ turers. Many companies include datasheets on all ICs that they manufacture, as well as application circuits and pricing and availability data. Some web sites, such as National Semiconductor’s, even allow the user to search for a device name and/ or number to find a datasheet for an un­known device. This service is very handy when you have an unknown IC and want to get more information on it. All datasheets and applica­tion notes are in the *.pdf format and require a reader such as Adobe Acrobat Reader Ver. 2.1 or later. This software can be downloaded from the National Semiconductor or Adobe web sites. It will be compressed in the pkzip format and is easily ex- panded using any pkunzip compatible archiving utility. A feature of some IC manufacturer web sites, such as the Motorola Semiconductor site, is a fax back feature. With this, the user can request that a datasheet be faxed to his/her fax machine by simply selecting the datasheet required and entering the phone number. Failing this, some web sites offer a “snail mail” service which allows the selected information to be mailed to the address entered at the prompt. With the microcontroller industry booming, the Internet can be the best way to select a family of chips to use. Most manufac­turers are represented on the Internet. This allows easy compari­son with opposition systems so that the one that best suits your needs can be selected. After browsing the Parallax web site, I decided that their Basic Stamp looked like a fun toy and ordered one. Be warned – lock away your wallet before browsing web pages! As well as the microcontroller sites that are run by the manufacturers, there are quite a few sites that are conducted by electronics enthusiasts who have fallen “in love” with a particu­lar type of microcontroller. These sites usually have a deluge of circuits using the microcontroller in question, with some of the circuits being quite novel and ingenious. Probably the best feature of these sites, however, is that their owners are usually happy to answer any questions/prob­lems relating to their particular microcontroller. Links to the best of these sites are sometimes also included in the manufacturer’s sites. Fig.2: the National Semiconductor IC data page menu. You can download selected information and even download the Adobe Acrobat reader if you don’t already have a copy. Circuit databases There are also many web sites and ftp (file transfer proto­ col) servers which contain databases of small circuits, along with short descriptions. Many of these circuits are quite novel, while some are downright strange in their uses of standard components. The sites also contain the standard boring building block cir­ cuits such as two trillion uses for a 555 timer and so forth. Along with such sites, which are usually operated by uni­ versities or electronics enthusiasts, are similar sites run by commercial companies, or for commercial companies by workers or private enthusiasts. The Parallax ftp Fig.3: this National Semiconductor data page shows information on the LMX2216 low-noise amplifier/mixer IC. Clicking on the download icon allows the datasheet to be downloaded. site contains quite a few circuits using their microcontrollers, as well as links to simi­lar sites. Shareware Electronic related shareware is available freely on the Internet. Indeed, many ftp and web sites dedicat- ed to electronics will have several directories containing useful programs. These are usually split into various categories such as PC board design and manufacture, schematic plotting and CAD programs, simulation programs of various types, and educational files. All of these files will be archived in August 1996  5 Fig.4: the Parallax homepage. It offers information on the Basic Stamp and PIC microcontrollers, includes quite a few circuits, and has links to various other sites that offer circuits. some way and can be downloaded in the standard fashion. As well as these shareware programs, many commercial soft­ ware manufacturers place demonstration packages of their software on web/ftp sites. This type of software is usually either a “crippled” version of the real thing or a much older superseded version. In either case, this software is good enough for demon­stration purposes and gives the user the opportunity to “try before buying”. Mail order stores As the Internet’s popularity increases, many mail order electronics stores are setting up web sites on which users can browse their goods catalog and even select, order and pay for their goods. While this trend is a bit sluggish taking off in Australia, there are many electronics dealers overseas who sell goods via the World Wide Web. The fact that a price for the same component can be obtained from dozens of shops from around the world in a few minutes really allows for customers to come out on top. A tip to buying goods is to know what you are looking for from the outset and do a web search on the item. If you are uncomfortable giving credit card details to an unknown company halfway around the world, send them a cheque by “snail mail” instead. It is also now possible to consult with several PC board design and production companies on the web. Whilst these business transactions can’t be carried out fully online, it is possible to get some idea of what the various companies have to offer, what type of pricing to expect, and previous examples of their work. Marketing Once your perfect circuit is up and running, the Internet is a great way to get it onto the market. It is possible to obtain quotes on various components in high quantities from specialist wholesale dealers and you can even try negotiating a deal to supply the finished product to one of the web’s electron­ics dealers. An alternative to this is to set up your own web site to advertise your products. If you do decide that your own web page is the way to go, a good way to increase the number of hits it receives is to con­vince an established electronics web site to include your site as one of its links. News groups Fig.5: the Motorola Semiconductor Products homepage. A feature of the Motorola site is a fax-back facilitity. 6  Silicon Chip Those who encounter a brick wall when designing or repair­ ing a circuit should try the electronics news groups. A search of “electronics” will give a list of several different news groups dedicated to divergent disciplines of electronics. Make sure that the one you select is the relevant one for your problem, as not doing so can make the users of the newsgroup you mail quite irate. After selecting the appropriate news group, post a letter stating your problem clearly. Be sure to include your email address so that the solution Web sites To Try The web sites listed below are among my favourites and are invaluable for any electronics work. Note, however, that they represent just a tiny fraction of the web sites that deal with electronics – there are thousands of others. http://www.hitechsurplus.com/ High-tech surplus goods for sale from North America http://www.natsemi.com/ National Semiconductor homepage http://www.parallaxinc.com/ Parallax homepage Fig.6: this screen shows the Motorola datasheet page. You can ask questions by clicking the Tech Support icon and then filling in the on-screen form. to your problem can be forwarded to you. After posting your problem, read through a few other peo­ple’s problems and try to solve them as this keeps the news groups going. Although the advice given on news groups is very helpful, with many electronic professionals giving advice, the advice given should never be taken as gospel. Also, while most conversa­tions that go on in the news groups deal with standard electronic problems and can be very educational, readers should be very wary of some of the topics discussed. On the day I accessed the news ­groups to research this arti­cle, 10 of the postings dealt with a person who wanted to con­struct a 1,000,000V tesla coil in his garage after seeing a tesla coil on a television science show. Most of the advice told him not to attempt it if he valued his life, as it was not the type of experiment to be attempted by a beginner. Another 18 postings dealt with a student who wanted information on constructing an electromagnetic gun to fire metal stakes! quite well supported, with web pages containing information on the elec­ tron­ics involved. There is also a model rocketry newsgroup where problems are quickly solved or, if necessary, forwarded to one of the electronics news groups. Other hobbies that are supported include radio controlled models and SC model trains. http://www.hutch.com.au/~oztech/oztech.htm Oztechnics homepage http://motserv.indirect.com/ Mototola homepage http://www.mot.com Motorola corporate homepage http://www.ee.ualberta.ca/html/ cookbook.html Electronic cookbook Archive Related sites As well as the resources described above, there are many web sits and news groups that deal with the electronics aspects of various hobbies. Model rocketry, a hobby of mine, is Fig.7: Adobe’s Acrobat reader is being used here to display the datasheet on the National Semiconductor LMX2216 0.1-2GHz low noise amplifi­er/mixer. August 1996  7