During consulting assignments, I constantly see engineers struggle to achieve EMC compliance, either emissions or immunity. This not only includes regulatory approval and functionality but also managing an in-house system that may not have been designed to include EMC and safety approvals. They are left on their own to experiment using trail-and-error techniques because management refuses to spend a little amount of money by bringing in a consultant or to send their engineers to a training class on both theory and applied application engineering directly related to their work.
The more senior one is at in design engineering, such as digital circuitry and printed circuit board layout, there is the tendency to do things in a manner that is familiar to them. What has been known to work in the past no longer applies due to advances in semiconductor technology and speed of operation, along with required packaging in a lightweight plastic enclosure instead of metal box. Time, money and extended effort is required, sometimes now with several engineers instead of one to solve what is probably a simple design or layout problem. These problems may be easy to visualize not only on the actual printed circuit board itself but also by looking at a schematic to find a design flaw such as a resistor used instead of a ferrite bead. If one had knowledge related to advances in high-speed signal integrity along with design concerns, our job of achieving compliance becomes easier.
Most EMC engineers use only a spectrum analyzer to find problem areas on a PCB. After spending lots of time using a sniffer probe to locate where energy is coming from, if even successful, what do they do next? They now go again into a trial and error mode of trying fixing the problem. Whenever I get called to troubleshoot an EMI problem (frequency domain) as a consultant at the printed circuit board level, I use an oscilloscope to locate the source in the time domain. A spectrum analyzer only tells us there is an RF field present, not what created the undesired RF energy. RF energy is created due to losses within a transmission line, which is commonly referred to as a trace. It is impossible to isolate losses with a spectrum due to many second order effects that occur during layout on a physical structure; core and prepreg.
In order to understand advances in circuit analysis and transmission line theory, continued education is required. There are many places to learn that includes seminars (even at your own expense if the company does not want to pay), attendance at conferences, reading technical papers that are free on-line and networking with others. The manner in how you obtain continued education is up to you, as long as you stay current with technology and are willing to learn and accept new ideas that may sound bizarre. If you are not willing to pay for training out of your own pocket to ensure job security and to make your life easier at work with quicker success, then do you deserve to be employed by a company that is willing to replace you with someone else, usually at lower cost, to increase their revenue by not providing support to them employees such as continued education?
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