Past Columns

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.

Learn how to calculate RC snubber values to eliminate parasitic ringing in power electronics circuits. This step-by-step guide covers measuring ringing frequency, estimating stray inductance and capacitance, and selecting Rs and Cs values to damp resonance and reduce EMI.

Can the hi-pot test and the insulation resistance test be combined into a single measurement? Let’s discuss each of these parameters as circuit parameters and as safety parameters.

Audio rectification is a common EMI problem in which high-frequency RF signals interfere with low-frequency audio circuits, producing audible noise or distortion. This article explains the causes of audio rectification, demonstrates TDMA/GSM effects on speakers, and offers practical EMI mitigation techniques for designers.

For production-line testing, the 25- or 30-amp grounding continuity test is not likely to identify construction anomalies that would not also be identified by a simple low-current test.

High-current grounding impedance tests have been specified in safety standards for many years. There are two, independent sources for these tests.