An electrical power and/or electrical signal transmission system for transmitting electrical power and/or electrical signals from a location on a first side of a metallic wall to a location on a second side of the metallic wall includes a transmitting apparatus having an electrical source and a first transformer. A receiving apparatus has a receiving module for receiving electrical power and/or electrical signals and a second transformer. First and second ends of a primary winding of the second transformer are electrically connected to respective spaced locations on the second, opposite, side of the metallic wall for picking up electrical power and/or electrical signals from the metallic wall. The receiving module is electrically connected to a secondary winding of the second transformer to enable electrical power and/or electrical signals to be transmitted from the electrical source to the receiving module.