The SC contact runs at a constant 100Hz, .5 microsecond pulse at high voltage. While it CAN be used alone, I am not sure what effectiveness it would have.
Remote targets the cell already, so it doesn't need help getting inside the cell.
Two contact pairs is never recommended, so I don't see an applicability to use the SC Contact on its own, without other frequency input to either the Plasma or the Ultrasound wand.
PEMF and Contact can both be run from the Central unit by just connecting power to Central and switching on the power switch and the PEMF / Contact switch.
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