a Robertson device coupled to said first count signal and said second count signal, and having as {HEAD ~ an output} {TAIL ~ a correlation signal} 
a Robertson device coupled to said first count signal and said second count signal , and having as { HEAD ~ an output } { TAIL ~ a correlation signal }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD TAIL TAIL TAIL TAIL TAIL TAIL TAIL