the circuit only during initial calibration of the system when it may be used to position the cx 12 and or rx 16 coils and or to adjust the parameters of the cx 12 and or rx 16 coils such that the combined signal from the rx and cx due to direct pickup of the tx field is at a minimum this methodology ensures that the calibration analog signal emanating from the cx precisely matches the amplitude and phase of the rx analog signal due to direct pickup of the tx field fig9 shows a two dimensional embodiment of the array conductivity meter acm for the case with three receiver assemblies m 3 case in which the transmitter tx 10 is located at the center of the array hatched ring the three receiver assemblies rx 1 rx 2 and rx 3 80 82 and 84 respectively are disposed symmetrically at the vertices of an equilateral triangle at distances r rx from the transmitter large solid rings and the calibration coil cx 12 is located in proximity to the tx for example at location cx a between the transmitter tx and the receiver assemblies or cx b inside the transmitter fig1 shows a two dimensional embodiment of the acm for the case with four receiver assemblies m 4 case in which the transmitter tx 10 is located at the center of the array hatched ring the four receiver assemblies rx 1 rx 2 rx 3 and rx 4 90 92 94 and 96 respectively are disposed symmetrically at the vertices of a square at distances r.