This standard establishes mandatory Radio Frequency/Intermediate Frequency (RF/IF) and associated interface requirements applicable to Satellite Communications (SATCOM) Earth Terminals (ET) operating over military X band and Ka band Super High Frequency (SHF) channels. Military unique requirements for ETs that may operate over commercial C-band, Ku-band, and Ka-band are included. Equipment developers may exceed the requirements herein to satisfy specific program requirements, provided that interoperability is maintained. Thus, incorporating additional standard and nonstandard capabilities and interfaces is not precluded. Existing certified SHF SATCOM terminals which predate this revision may not need to conform to this MIL-STD unless they undergo modernization or modifications which alter performance for requirements listed herein.