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SET is a unit or units and the assemblies, subassemblies, and parts connected or associated together
to perform a specific function.
GROUP is a collection of units, assemblies, subassemblies, and parts. It is a subdivision of a set or
system but is not capable of performing a complete operational function.
UNIT is an assembly or any combination of parts, subassemblies, and assemblies mounted together.
Normally capable of independent operation.
ASSEMBLY is a number of parts or subassemblies, or any combination thereof, joined together to
perform a specific function.
SUBASSEMBLY consists of two or more parts that form a portion of an assembly or a unit.
PART is one component or two or more components joined together. It is not normally subject to
disassembly without destruction.
EXTREMELY LOW FREQUENCY is the band of frequencies up to 300 hertz.
VERY LOW FREQUENCY is the band of frequencies from 3 kilohertz to 30 kilohertz.
LOW FREQUENCY is the band of frequencies from 30 kilohertz to 300 kilohertz.
MEDIUM FREQUENCY is the band of frequencies from 300 kilohertz to 3 megahertz.
HIGH FREQUENCY is the band of frequencies from 3 megahertz to 30 megahertz.
VERY HIGH FREQUENCY is the band of frequencies from 30 megahertz to 300 megahertz.
ULTRAHIGH FREQUENCY is the band of frequencies from 300 megahertz to 3 gigahertz.
SUPERHIGH FREQUENCY is the band of frequencies from 3 gigahertz to 30 gigahertz.
EXTREMELY HIGH FREQUENCY is the band of frequencies from 30 gigahertz to 300
gigahertz.
