{TAIL ~ The signal} at {HEAD ~ the collector} of transistor 168 is then applied to the base of a current drive NPN transistor 186 via a diode 178 
{ TAIL ~ The signal } at { HEAD ~ the collector } of transistor 168 is then applied to the base of a current drive NPN transistor 186 via a diode 178
TAIL TAIL TAIL TAIL TAIL TAIL OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH