Chapter 19 – Regulatory Issues

Governments have long considered electromagnetic interference (EMI)/electromagnetic compatibility (EMC) to be among their functions, and as such have issued a number of standards and regulations. The technical vocabulary of EMI/EMC is given in a document called IEC-50. It has definitions given in three languages. In the case of radio transmitters, there is a method for complying with the law, and that is approval by the British Approvals Boards for Telecommunications (BABT). The BABT is also the approval unit for telecommunications terminal equipment connected to telephone lines. For straight EMI/EMC testing, the OATS is sufficient because reflections do not bother EMI/EMC tests as much as they do antenna patterns. A decent job of EMI/EMC testing can be done inside a screened room, rather than an anechoic chamber. The screened room is basically a Faraday cage.