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