fourth detector means electrically coupled to said second coil means for amplitude detecting {HEAD ~ changes} in RF signals generated across {TAIL ~ a down sensor segment} of said second coil means, and for generating a down output pulse 
fourth detector means electrically coupled to said second coil means for amplitude detecting { HEAD ~ changes } in RF signals generated across { TAIL ~ a down sensor segment } of said second coil means , and for generating a down output pulse
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH