FIELD-EFFECT TRANSISTOR (FET)A transistor consisting of a source, a gate, and a drain.
Current flow is controlled by the transverse electric field under the gate.
FIDELITY-The faithful reproduction of a signal. The accuracy with which a system reproduces a
signal at its output that faithfully maintains the essential characteristics of the input signal.
FIXED BIASA constant value of bias voltage.
FORBIDDEN BANDThe energy band in an atom lying between the conduction band and the valence
band. Electrons are never found in the forbidden band but may travel back and forth through it. The
forbidden band determines whether a solid material will act as a conductor, a semiconductor, or an
FORWARD BIASAn external voltage that is applied to a PN junction in the conducting direction so
that the junction offers only minimum resistance to the flow of current. Conduction is by majority
current carriers (holes in P-type material; electrons in N-type material).
FREE CHARGESThose electrons that can be moved by an externally applied voltage.
FULL-WAVE RECTIFIERA circuit that uses both positive and negative alternations in an
alternating current to produce direct current.
FULL-WAVE VOLTAGE DOUBLERConsists of two full-wave voltage rectifiers and is used to
reduce the output ripple frequency.
FUSED-ALLOY JUNCTIONSee ALLOYED-JUNCTION.
GALENAA crystalline form of lead sulfide used in early radio receivers.
GAMMAThe emitter-to-base current ratio in a common-collector configuration.
GERMANIUMA grayish-white metal having semiconductor properties.
GROWN JUNCTIONA method of mixing P-type and N-type impurities into a single crystal while the
crystal is being grown.
HALF-WAVE RECTIFIERA rectifier using only one-half of each cycle to change ac to pulsating dc.
HALF-WAVE VOLTAGE DOUBLERConsists of two half-wave voltage rectifiers.
HOLE FLOWIn the valence band, a process of conduction in which electrons move into holes,
thereby creating other holes that appear to move toward a negative potential. (The movement of
holes is opposite the movement of electrons.)
HYBRID CIRCUITA circuit where passive components (resistors, capacitors) are deposited onto a
substrate made of glass, ceramic, or other insulating material. Then the active components (diodes,
transistors) are attached to the substrate and connected to the passive components on the substrate
with a very fine wire.
IGFETAny field-effect transistor that has an insulated gate.
INDUCED CHANNEL MOSFETA MOSFET in which there is no actual channel between the source
and the drain. This MOSFET is constructed by making the channel the same type of material as the