A practical comparison of cabling effects on radiated emissions

External cables are one of the major sources of radiated emissions. Theoretical and practical effects of cable shielding, and the use of ferrites have been analyzed in previous studies under test conditions such as noise source, cable, termination setup´s etc. We have looked at cabling effects from a practical point of view. We measured radiated emissions of a typical IT device with Ethernet and RS232 connections under a variety of conditions. We varied cable shielding, shield grounding, used ferrites at different locations and compared the results. The results show that shield type and grounding have a more significant impact on radiated emissions than use of ferrites, with the exception of internal components (filtered connectors)