The amplitude of {HEAD ~ the output} of {TAIL ~ receiver} 24 is sampled by sample/hold circuit 171 
The amplitude of { HEAD ~ the output } of { TAIL ~ receiver } 24 is sampled by sample / hold circuit 171
OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH