demodulating the modulated signal supplied to {HEAD ~ the second electrode} in {TAIL ~ the second liquid container} 
in
demodulating the modulated signal supplied to { HEAD ~ the second electrode } in { TAIL ~ the second liquid container }
OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL