control means for supplying {TAIL ~ a control signal} varying the inductance of {HEAD ~ the inductive means}, 
control means for supplying { TAIL ~ a control signal } varying the inductance of { HEAD ~ the inductive means } ,
OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH