Thursday, July 30, 2009

A glowing future

Ever since I was young, I have always liked taking things apart, and my father, being a mechanical engineer, was only too willing to encourage me in my endeavors. And so in 1979 when his expensive, wooden cabinet-sized tube-based stereo system failed, I decided to attempt to repair it.


After my brother and I lifted the cabinet to the center of the living room, I unscrewed the stiff card backing of the machine and peered inside. There, in a large metal chassis was an array of valves that stood proudly in shiny round sockets.


I instructed my brother to turn the equipment on while I watched to see what happened. During the next few moments, theglass valves began to warm up and emit their eerie orange glow. That is, of course, all but one. This, I thought must be the culprit so, after turning off the stereo system and letting it cool down for ten minutes, I removed the valve in question.


Being a member of the press, I then tried to leverage my contacts at Philips to obtain a free sample of the Mullard valve in question. After being informed that Philips had not made the product for more than ten years, I was told that they could be obtained from a small company in India. My contact generously offered to obtain the product for me and ship it to my dad's house. I was delighted.


Several weeks later, a package arrived at the door from Philips. Excitedly, I opened the package and gazed upon the shiny newdevice. Following the same procedure as before, I located the socket of the defunct tube and placed in the new one.


To my delight, after switching the stereo system on, the voice of a BBC newscaster sprang from the speakers. Without engineering drawings, signal generators, or oscilloscopes, I had brought the stereo back from the dead. Even my old man could not believe it. In the decades that followed, valves were replaced by discrete transistors, transistors by TTL logic, and TTL logic by microprocessors, VLSI devices, and gate arrays. And, of course, everything is now smaller. In the machine-vision industry, for example, system integrators can now purchase a smart camera replete with sensor, CPU/DSP, memory, interface, and on-board software for less than $2,500.


System integration par excellence
Nowhere, however, has this level of integration been more significant than in the development of consumer products. To develop products such as mobile telephones, MP3 players, and portable televisions, engineers use sophisticated electronic and mechanical CAD packages rather than data sheets and drawing boards.


Using these packages, it is possible to cram more technology into a single square inch than ever before. And, if well designed, these products are less expensive, more reliable, and longer lasting than any valve-based system could ever expect to be. For those tasked with repairing such devices the task is more complex. More than likely, should the devices fail under warranty, they are replaced free of charge by the manufacturer.


Today, it has become more expensive to repair these devices than replace them with new ones. Although this is not yet the case in much of the machine-vision industry, those developing products for this market are also concerned with reducing cost and size.


To gain an advantage in this area, inquisitive engineers may want to take a look at what their counterparts have accomplished in the consumer market. Although purchasing every latest miniature device, tearing it apart, and characterizing each design may not be a wise idea, companies such as Portelligent (Austin, TX, USA; www.teardown.com) have emerged that can provide this data for you.


Replete with external and internal photographs, parts lists, component counts, and a manufacturing cost analysis, the reportscould provide you with just the edge you need when developing your next product. And you will not need a screwdriver, signal generator, or an oscilloscope -- just a check or credit card.