Definition of phantom circuit in English:

phantom circuit


  • An arrangement of telegraph or other electric wires equivalent to an extra circuit.

    • ‘Engineers commonly called duplexed telephone circuits ‘phantom circuits’ or simply ‘phantoms.’’
    • ‘If a telephone company was not happy with a gain of one circuit from two pairs, they could always take two phantom circuits, additional repeat coils and "phantom the phantoms" to obtain seven circuits over four pairs of wire.’