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Looking at the datasheets, SSA3015X Plus and SVA1015X have identical 1.5 GHz spectrum analyser specs however the SVA instrument has one additional option as listed below.
Common to both:
EMI activation license
Advanced measurement activation license
Digital modulation analysis (ASK/FSK) activation license
Analog modulation analysis (AM/FM) activation license
Specific to SSA3015X Plus:
VSWR/Return Loss activation license (this capability is standard/free in the SVA1015X VNA mode)
Specific to SVA1015X:
Distance-to-fault activation license
Interesting exercise.
