Keysight Technologies B1500A Self-Paced Training Manual page 33

Module 2
Basic Measurement
A subordinate sweep variable (VAR2) may be combined with the basic sweep variable (VAR1).
This corresponds to the step knob and sweep knob of a curve tracer. This produces a family of
curves. VAR2 may be called the secondary sweep.
Another useful combination is a synchronous sweep. Here VAR1 and VAR1' are in-step. VAR1'
defaults to a gain of 1, which means it exactly tracks VAR1. You can also vary the initial offset
between VAR1 and VAR1'. These features are useful for bipolar gummel plots, op-amp differential
input tests, etc.
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