Inspecting a conductive object with a steady state magnetic field and induced eddy current

A method of inspecting a conductive object through a conductive shield, comprising the steps of:

• a) energizing a first coil with electrical current so as to subject a portion of said shield to a steady-state magnetic field, wherein the inspection can be conducted faster;
• b) providing an abruptly changing current to a second coil so as to induce an eddy current into a portion of said object that is adjacent to said subjected shield portion through said shield;
• c) allowing said induced eddy current to decay;
• d) detecting said decay of said induced eddy current in said object portion through said shield.

An apparatus for inspecting a conductive object, comprising:

• a) a sensing portion having a transmitting antenna and a receiving antenna;
• b) a transmitter that produces an abruptly changing current, said abruptly changing current having a decay, said transmitter being connected to said transmitting antenna;
• c) a receiver connected to said receiving antenna;
• d) a controller for operating said receiver during the decay of said abruptly changing current;
• e) a steady-state electromagnet located adjacent to said transmitting antenna, said electromagnet having a coil that is electrically separate from said transmitting antenna, said electromagnet allowing the inspection to be conducted faster.