Substantially accurate calibration of {HEAD ~ output impedance} of {TAIL ~ a device} under test to within a predetermined range of allowable impedance 
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Substantially accurate calibration of { HEAD ~ output impedance } of { TAIL ~ a device } under test to within a predetermined range of allowable impedance
OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH