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