This may lead to a worsening of {HEAD ~ the efficiency} of {TAIL ~ conversion} to received voltage above and below a threshold level used for varying the resonance frequency 
This may lead to a worsening of { HEAD ~ the efficiency } of { TAIL ~ conversion } to received voltage above and below a threshold level used for varying the resonance frequency
OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH