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FLAT PACK—An IC package [14].
FLEMING VALVE—An earlier name for a diode, or a two-electrode vacuum tube used as a detector [6].
FLEXIBLE COAXIAL LINE—A line made with an inner conductor that consists of flexible wire
insulated from the outer conductor by a solid, continuous insulating material [10].
FLIP CHIP—A monolithic IC packaging technique that eliminates the need for bonding wires [14].
FLIP-FLOP—A device having two stable states and two input terminals (or types of input signals), each of
which corresponds with one of the two states. The circuit remains in either state until caused to change
to the other state by application of a voltage pulse. A similar bistable device with an input that allows it
to act as a single-stage binary counter [13].
FLUX—(1) In electrical or electromagnetic devices, a general term used to designate collectively all the
electric or magnetic lines of force in a region [1]. (2) A solution that removes surface oxides from
metals being soldered [2] [14].
FLUX DENSITY—The number of magnetic lines of force passing through a given area [1].
FLYWHEEL EFFECT—The ability of a resonant circuit to operate continuously because of stored energy
or energy pulses [9].
FOCUSING ANODE—An electrode of a CRT that is used to focus the electrons into a tight beam [6].
FOLDED DIPOLE—An ordinary half-wave antenna (dipole) that has one or more additional conductors
connected across the ends parallel to each other [10].
FORBIDDEN BAND—The 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 semi-conductor, or an
insulator [7].
FORWARD AGC—The type of AGC that causes an amplifier to be driven towards saturation [17].
FORWARD BIAS—An 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 accomplished by
majority current carriers (holes in P-type material; electrons in N-type material) [7] [13] [14].
FORWARD RESISTANCE—The smaller resistance value observed when you are checking the resistance
of a semiconductor [16].
FOSTER-SEELEY DISCRIMINATOR—A circuit that uses a double-tuned RF transformer to convert
frequency variations in the received FM signal to amplitude variations. Also known as a phase-shift
discriminator [12].
FOUR-ELEMENT ARRAY—An antenna array with three parasitic elements and one driven element [10].
FRAMING—The process of synchronizing a facsimile receiver to a transmitter. This allows proper picture
reproduction [17].
FREE CHARGES—Those electrons that can be moved by an externally applied voltage [7].
