{HEAD ~ The magnitude} of {TAIL ~ delay} is varied between these two extremes by varying the relative levels of operation of the differential sections D1 and D2 
of
{ HEAD ~ The magnitude } of { TAIL ~ delay } is varied between these two extremes by varying the relative levels of operation of the differential sections D1 and D2
HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH