OSCILLATION TRANSFORMER.--See Transformer.

OSCILLATION VALVE.--See Vacuum Tube.

OSCILLATOR TUBE.--A vacuum tube which is used to produce electric oscillations.

OVER MODULATION.--See Blub Blub.

PANCAKE OSCILLATION TRANSFORMER.--Disk-shaped coils that are used for receiving tuning inductances.

PERMEABILITY, MAGNETIC.--The degree to which a substance can be magnetized. Iron has a greater magnetic permeability than air.

PHASE.--A characteristic aspect or appearance that takes place at the same point or part of a cycle.

PICK-UP CIRCUITS.--See Circuits, Stand-by.

PLATE CIRCUIT REACTOR.--See Reactor, Plate Circuit.

PLATE CURRENT.--See Current, Plate.