The phase locked loop system has a lock frequency range which decreases its width when the level of {HEAD ~ the input angle modulated wave} is below {TAIL ~ a predetermined level} 
is below
The phase locked loop system has a lock frequency range which decreases its width when the level of { HEAD ~ the input angle modulated wave } is below { TAIL ~ a predetermined level }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL