The voltage comparator produces a first signal when {HEAD ~ the detected signal} is below {TAIL ~ the squelch level} and produces a second signal when the detected signal is above the squelch level 
is below
The voltage comparator produces a first signal when { HEAD ~ the detected signal } is below { TAIL ~ the squelch level } and produces a second signal when the detected signal is above the squelch level
OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH