Revision F of ED-73, MOPS (Minimum Operational Performance Standard) for Secondary Surveillance Radar Mode S Transponders. The document has been updated to include changes coming from field experience and from new functionalities linked to the new ADS-B version and ACAS X. As compared with the previous version, the main changes are: -Reduction of minimum level 2 transponder capabilities to surveillance and GICB capabilities, -New requirement to limit RF output power transmitted before, between and after the pulses of a reply, -Introduction of Mode Reply Rate Limiting function, -Air/ground status determination clarification, -ACAS X capability reporting and messages, -Alignment of register 2016 management on register 0816, -New transponder register formats, -Cleaning of EHS tests, -Phase overlay modulation and messages over long Mode S replies option, -Basic dataflash capability and removal of old dataflash capability option, -Interrogation and reply monitoring measurement and messages option.