EMC Bench Notes

This month's EMC Bench Notes reviews three affordable pre-compliance measurement software options that can simplify and automate the process of conducting in-house radiated emissions testing, saving time and costs compared to manual methods.

Discover pre-compliance testing for automotive and military EMC standards. Learn key differences from commercial testing, setup techniques, and tips for dealing with ambient signals. Save thousands in wasted compliance testing.

Ken Wyatt provides an overview of radiated emissions pre-compliance testing. He covers equipment setup, field strength calculations, and strategies for managing ambient interference. The guide aims to enhance EMC troubleshooting skills and reduce formal testing expenses.

Ken Wyatt's blog explores DIY radiated emissions testing. He breaks down the gear you'll need—think spectrum analyzers and special antennas—and shows how to set up your own test space without breaking the bank. It's all about catching EMC issues before the big, pricey lab tests.

While many designers attempt to perform radiated emissions troubleshooting at an outdoor site or in a semi-anechoic chamber using a third-party test lab facility, I've found a much more efficient method is to perform this using a nearby antenna right on your own work bench.

Ken Wyatt explores a more advanced troubleshooting tool for assessing radiated emission issues, the RF current probe. These are most useful for measuring RF common mode harmonic currents on cables.

Most engineers are familiar with near-field probes and that they are sensitive to E- or H-fields emanating from circuit boards, cables or enclosure seams. They are really the first order of business when evaluating a circuit board or system.

Let's use the basic tools and spectrum analyzer setup described in the last two months and use them to characterize an actual embedded processor board based on the Arduino design.

Spectrum analyzers are usually the tool of choice for troubleshooting CE or RE. In recent years, the cost of a basic analyzer has dropped markedly. However, the more expensive lab-quality analyzers will have advanced measurement features that may be worth considering.

As a product designer, a major issue you'll face is radiated emissions. This month, we'll outline the basic tools to characterize and mitigate radiated emissions at your workbench. This summarizes the fundamental test equipment to identify sources of harmonic noise and characterize radiated emissions.