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