Bias for transistor 168 is provided by {HEAD ~ current} via {TAIL ~ return resistor} 174 coupled between the base thereof and the voltage source A 
Bias for transistor 168 is provided by { HEAD ~ current } via { TAIL ~ return resistor } 174 coupled between the base thereof and the voltage source A
OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH