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Figure 4: Electrical output during bipolar (2-electrode) stimulation
measured across the capacitive element of the AAMI load.
This shows the interaction of the carrier frequency and
adjustable frequency which takes place internal to the
stimulator. The interference frequency is evident as an
“envelope” of stimulation occurring at 100 Hz. This figure
is provided to illustrate interferential stimulation, but does
not correspond exactly to the output which an oscilloscope
would record with a skin load.
Figure 5: A conceptual diagram of quadrapolar (4-electrode) stimulation
with interference taking place within the tissue.