Agilent Technologies 89410A Operator's Manual page 232

What Makes this Analyzer Different?
The difference between swept-tuned and stepped analyzer technology in local oscillator
function
A swept-tuned analyzer
changes the local oscillator
frequency linearly over time
and measures one frequency
point at a time
A stepped analyzer like the HP
89400 series changes the
local oscillator frequency in
sequential steps over time and
measures multiple frequency
points at one time
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