Measurement of emissions and immunity on telecommunication lines-a universal ISN concept for unshielded cables

The new editions of CISPR 22/EN 55022 as well as CISPR 24/EN 55024 require testing of emission and immunity on telecommunication ports of information technology equipment (ITE) and telecommunication equipment. Different versions of impedance stabilization networks (ISNs) are required for the different conformance alternatives and cable categories. Since there is a great variety of systems with different pin connections of the Western RJ45 connector, a solution with a basic universal network using a universal interface and a series of adapters has been chosen. A high-performance balun has been developed for verification and calibration. Imperfections of the CISPR 22 standard are discussed together with characteristics and proposed amendments of CISPR 16-1 for ISN characterization and calibration.