Start here: Electromagnetic compatibility means equipment can operate in its intended environment without causing or suffering unacceptable electromagnetic interference.
Why this changes a real station
EMC is a system property involving emissions, immunity, cable routing, shielding, filtering, bonding, grounding, software states, and antenna placement.
What it looks like in practice
A radio can pass a laboratory test yet still interfere with a nearby device through an installation-specific cable acting as an antenna.
What to do next
Reproduce the problem, identify the coupling path, change one variable at a time, and suppress noise or RF at the source and entry point.
Evidence boundary
Keep frequency, reference plane, antenna geometry, losses, measurement method, and safety conditions attached to the conclusion. A match, a DC check, or one field symptom does not prove efficiency or identify the complete RF path.
