this I feel is a typical troubleshooting scenario. many a times lack of understanding of the topology of the circuit , component charactetistics may result in this. for example an opamp based schmitt trigger may appear like a non inverting amplifier ( first impression on circuit topology) and if one has to torubleshoot a problem , lack of understandign of the topolgy may create more errors than a possilble solution.
Rob, it may be more cynically stated that "the customer always lies." Or, at least, "the customer never tells the whole truth." Troubleshooting such problems almost always means you have to be a Missourian: "Show me" or it didn't really happen.
Here's another good example of why it's important to dig down to the real problem. What appears to be the problem at first may not actually be the problem. We're seeing this again and again in the Sherlock Ohms posts.
Altair has released an update of its HyperWorks computer-aided engineering simulation suite that includes new features focusing on four key areas of product design: performance optimization, lightweight design, lead-time reduction, and new technologies.
At IMTS last week, Stratasys introduced two new multi-materials PolyJet 3D printers, plus a new UV-resistant material for its FDM production 3D printers. They can be used in making jigs and fixtures, as well as prototypes and small runs of production parts.
In a line of ultra-futuristic projects, DARPA is developing a brain microchip that will help heal the bodies and minds of soldiers. A final product is far off, but preliminary chips are already being tested.
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