Additional information on Bio-feedback module
Added 2023-11-22 17:14:57 +0000 UTCHere is a photo and schematic PDF and a supplemental video of the common mode noise.
Common mode noise is noise that flows from sources other than the GND line.
The linked video shows how noise increases when touching the wall. That noise is the 60 Hz household power frequency.
The household power supply noise flows from the TENS pad through the body and through the wall to the module.
