{HEAD ~ a microprocessor} connected to {TAIL ~ the battery} through a regulator to obtain a suitable DC voltage, the power supply switch and the illumination switch 
connected to
{ HEAD ~ a microprocessor } connected to { TAIL ~ the battery } through a regulator to obtain a suitable DC voltage , the power supply switch and the illumination switch
HEAD HEAD HEAD HEAD HEAD HEAD REL REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH