When {TAIL ~ an input signal} of a low level is outside of the lock range characteristic of the phase locked {HEAD ~ loop}, a voltage controlled oscillator of the phase locked loop oscillates at a predetermined frequency 
When { TAIL ~ an input signal } of a low level is outside of the lock range characteristic of the phase locked { HEAD ~ loop } , a voltage controlled oscillator of the phase locked loop oscillates at a predetermined frequency
OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH