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A VSWR bridge and a magnetic near field probe (NFP) are very valuable tools to find resonances in RF and EMI/EMC applications as tuning, shielding, etc.

Usually HF filters are designed using inductors with cores. In this way a medium/high inductance value is obtained in small size components. But using cores has a limitation.

The mirror technique is a very old technique to be used with PCBs when failing in radiated EMC tests. An easy solution to avoid changes in layout if the technique can be applied to your product.

Clock signals from 1 to 100MHz are usually responsible for radiated EMC problems in HF/VHF range. Harmonics are the culprits, but think in current, not in voltage.

Inductive loads and interrupted currents are an explosive combination. High voltages, arcing, and HF broadband noise are some typical effects. The phenomena behind these transients is complex, but it is not difficult to understand the fundamentals and how to minimize the effects.

Snubbers are RC networks that are really useful for protecting components (transistors, diodes, etc.) and reducing EMI, especially in switching applications.

RF signals entering in a system and being rectified can interfere seriously. That has been classically the case of audio noise in speakers because of mobile phones using TDMA technology. The problem is now very common in products with wireless RF funcionality in products with audio areas.

Whenever an electronic circuit is first energized, transients occur in current and voltage waveforms. These start-up transients can affect the electrical and thermal behavior of components and circuits with serious reliability, EMI, and random effects. Try to characterize how your circuits start and stop.

Why do cables radiate? Common mode currents are the culprit. Through four practical experiments, learn how return paths, grounding switches, and parasitic capacitances determine whether your current stays differential—or becomes a radiating common mode problem.

When testing EMI performance, substituting real loads with "equivalent" resistors can mislead you by up to 20dB—enough to turn a passing design into a costly failure. This practical guide demonstrates why fans, motors, and other non-linear loads behave dramatically differently than resistors, and why authentic testing matters for accurate results.