Whitepaper
Making Conducted and Radiated Emissions Measurements
This application note details precompliance testing methodologies for electromagnetic interference (EMI) measurements, focusing on both conducted and radiated emissions. It outlines the importance of precompliance testing as a cost-effective method to identify and resolve EMC issues early in the product development cycle. Conducted emission tests cover the 9 kHz to 30 MHz frequency range, while radiated emissions are typically measured from 30 MHz to 1 GHz (potentially extending to 6 GHz or higher based on device clock speed). The document covers regulatory standards like FCC Part 15 and CISPR 11/22/14, detailing the necessary equipment – including LISNs, transient limiters, signal analyzers (like Keysight N6141C with N9311X-100 probes) – and procedures for accurate precompliance testing. It emphasizes distinctions between Class A and B compliance levels based on intended environment of use (industrial vs residential).