first encoder means for binary encoding {HEAD ~ a signal} obtained from said first means with {TAIL ~ a predetermined voltage level} 
first encoder means for binary encoding { HEAD ~ a signal } obtained from said first means with { TAIL ~ a predetermined voltage level }
OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL