At R&D Haaga Oy, we see it all the time: a great product idea gets delayed or nearly killed because of electromagnetic compatibility (EMC) issues that could have been avoided with a few early design choices.

Henry Ott’s classic Electromagnetic Compatibility Engineering puts it simply — the later you fix EMC problems, the more expensive they get. A trace reroute during layout might cost nothing; failing at a certification lab can cost thousands and weeks of delay.

In practice, most EMC problems aren’t mysterious. They come from fast edges, poor return paths, and shared grounds between noisy and sensitive circuits. For example, when switching a MOSFET too aggressively, the dV/dt spikes can radiate strongly into nearby traces. Slowing the transition slightly, or optimizing the gate resistor value, often makes the emissions drop dramatically without hurting performance.

Another common issue we see is noise coupling through microcontroller GPIO pins — especially when long cables or high-current loads are nearby. A few small ferrite beads or series resistors right at the MCU pins can make the difference between a clean design and a failed radiated emissions test.

Right now, we focus on near-field probing, schematic and layout reviews, and actual design work to help customers identify and eliminate these issues before the expensive test stage. Our measurements show exactly where the noise originates, and our design input ensures it doesn’t come back.

In the near future, we’re expanding our pre-compliance EMC capabilities in Helsinki, allowing local teams to measure, debug, and verify their products faster — without waiting for an accredited lab slot.

The lesson from Ott’s book still holds: treat EMC as part of design, not an afterthought. A little attention early saves a lot of pain later.

If you’re designing new electronics and want to build it right the first time, get in touch with us at R&D Haaga Oy