CONVENTIONAL SIGNALS.--See Signals, Conventional.

COUNTER ELECTROMOTIVE FORCE.--See Electromotive Force, Counter.

COUNTERPOISE. A duplicate of the aerial wire that is raised a few feet above the earth and insulated from it. Usually no connection is made with the earth itself.

COUPLED CIRCUITS.--See Circuit, Coupled.

COUPLING.--When two oscillation circuits are connected together either by the magnetic field of an inductance coil, or by the electrostatic field of a condenser.

COUPLING, CAPACITIVE.--Oscillation circuits when connected together by condensers instead of inductance coils.

COUPLING, COEFFICIENT OF.--The measure of the closeness of the coupling between two coils.

COUPLING, INDUCTIVE.--Oscillation circuits when connected together by inductance coils.

COUPLING, RESISTANCE.--Oscillation circuits connected together by a resistance.

CRYSTAL RECTIFIER.--A crystal detector.