Each transformer 28, in {HEAD ~ association} with {TAIL ~ the link} 18, thus serves to transmit signals between the surface installation 16 and the tool in question 
Each transformer 28 , in { HEAD ~ association } with { TAIL ~ the link } 18 , thus serves to transmit signals between the surface installation 16 and the tool in question
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