DO-160 Section 21 encompasses both conducted and radiated emissions testing. The intereference measuring instrument requirements is less stringent the CISPR 16 and other commercial EMC standards. A precompliant EMC spectrum analyzer will suffice as long as it covers the bandwidth requirements. Peak detection and selectable IF bandwidths are common in most every spectrum analyzer these days.
Section 21 defines limits, test procedures and requirements. In order to properly interpret the procedures and requirements outlined in Section 21, a User’s Guide is provided as an Appendix to Section 21.
The User’s Guide includes rationale, guidance and background information for the environment, test procedures and requirements, guidance in applying the requirements, and lessons learned from aircraft and laboratory experience.