AN IMPROVED METAL DETECTOR

Abstract A method for detecting a target using a metal detector, including: transmitting a transmit magnetic field using a transmitter; receiving a receive magnetic field due to the transmit magnetic field to produce a receive signal using a receiver and receive electronics; processing the receive signal using at least one function to produce an indicator output, wherein the at least one function is controllable such that the properties of the indicator output is controllable in terms of: (a) an amount of cancellation of signals due to soil; wherein the amount of cancellation of signals due to soil is higher than an amount of cancellation of signals due to the target; and (b) a sensitivity of the indicator output to the target and broadband electromagnetic interference (EMI); wherein controlling the at least one function in a particular direction changes the at least one function from a first state more suitable for high ground response environments to a second state more suitable for medium ground response environments; and controlling the at least one function again in the particular direction changes the at least one function from the second state more suitable for medium ground response environments to a third state more suitable for low ground response environments; and wherein when compared to the first state, the second state provides an indicator output that is more sensitive to a target, more sensitive to broadband EMI and more sensitive to the ground response; and when compared to the second state, the third state provides an indicator output that is more sensitive to a target, at least about as sensitive to broadband EMI and more sensitive to the ground. - - - - - -- -f --- ---5 11-f 7 Figure Figur 2 Fiure