a plurality of level control lines for sequent realization of {HEAD ~ said level combinations} by actuating {TAIL ~ said coils}, in accordance with sequence of actuated power levels 
by actuating
a plurality of level control lines for sequent realization of { HEAD ~ said level combinations } by actuating { TAIL ~ said coils } , in accordance with sequence of actuated power levels
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH