{HEAD ~ The emitter follower pair} is operative to receive an input differential voltage signal for shifting {TAIL ~ the input differential voltage signal} to develop a shifted differential voltage signal 
{ HEAD ~ The emitter follower pair } is operative to receive an input differential voltage signal for shifting { TAIL ~ the input differential voltage signal } to develop a shifted differential voltage signal
HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH