18WuD2x

full-scale symmetry • function generator 305
full-scale symmetry Expressed in microamperes
(mA). The mathematical difference between the
full-scale current outputs in a complementaryoutput
digital-to-analog converter.
full track A recording track covering the full width
of a magnetic tape.
full-track head A tape-recorder head having a gap
that covers the full width of the tape.
full-track recording Usually applicable to quarterinch
or narrower magnetic recording tape, a onetrack
recording made by a head that magnetizes
essentially the entire width of the tape.
full-wave bridge rectifier See BRIDGE RECTI-
FIER.
full-wave, center-tap rectifier A circuit in which
the center-tapped secondary winding of a transformer
operates two rectifier diodes, each on an
alternate half-cycle of secondary voltage. The frequency
of the ripple in the direct-current (dc) output
is equal to twice the alternating-current (ac)
input frequency. Compare BRIDGE RECTIFIER.
ac
in
full-wave, center-tap rectifier
+
Pulsating
dc out
full-wave detector A detector circuit using two
diodes in a full-wave, center-tap rectifier configuration.
full-wave doubler See FULL-WAVE VOLTAGE
DOUBLER.
full wavelength Symbol, λ. The distance that corresponds
to 360 degrees of phase as an electromagnetic
(EM) field is propagated. In free space, it
is related to the frequency by a simple equation:
L ft = 984/f
where L ft represents λ in feet, and f represents the
frequency in megahertz. If λ is expressed in meters,
then the formula is:
L m = 300/f
Where L m represents the displacement in meters.
In general, if ν is the velocity factor (expressed as
a ratio) in a given medium, then:
L ft = 984ν/f
and
L m = 300ν/f
Compare HALF WAVELENGTH, QUARTER
WAVELENGTH.
full-wave loop antenna A loop antenna with a circumference
of one wavelength, fed at a break. The
loop can be circular, square, triangular, or occa-
sionally some odd shape. The most efficient configuration
is the circular loop. Maximum radiation
occurs perpendicular to the plane of the loop.
full-wave rectifier A rectifier that delivers a halfcycle
of pulsating direct-current (dc) output
voltage for each half-cycle of applied alternatingcurrent
(ac) voltage. The successive output
half-cycles have the same polarity. See, specifically,
BRIDGE RECTIFIER and FULL-
WAVE, CENTER-TAP RECTIFIER. Compare
HALF-WAVE RECTIFIER.
full-wave vibrator 1. In a vibrator-type power supply,
an interrupter that closes contacts on both
ends of its swing, thus causing direct current (dc)
to flow through the transformer in alternate directions.
2. A vibrator-type rectifier that closes in
both directions.
full-wave voltage doubler A voltage-doubler circuit
whose direct-current (dc) output has a ripple
of twice the alternating-current (ac) supply frequency.
Compare HALF-WAVE VOLTAGE DOU-
BLER.
function 1. A mapping between two sets of quantities
or points A and B, such that: (1) For each y in
B, there exists at least one corresponding x in A;
and (2) For each x in A, there exists exactly one y
in B. In this case y is said to be a function of x;
this can be written as y = f(x). The set A is called
the domain of f; the set B is called the range of f.
2. A mathematical expression, using symbols, relating
variables (e.g., the expression x - y = z is a
function of variables x, y, and z). 3. The behavior
and application for which a device or system is
designed. 4. Part of a computer instruction specifying
the operation to be done.
functional blocks Combinations of substances or
components that perform specific tasks in an
electronic circuit. An example is a tuned circuit,
containing inductive reactance, capacitive reactance,
and resistance.
functional character See CONTROL CHARACTER.
functional design Design specifications encompassing
a description of how system elements will
interrelate, and what their logic design will be.
functional diagram FUNCTIONAL DESIGN represented
in graphic form; that is, as an illustration
or set of illustrations.
functional electronic block Abbreviation, FEB. A
complete integrated circuit. See INTEGRATED
CIRCUIT.
functional end (FE) point In a system operating
from a battery power supply, the lowest voltage at
which the equipment will properly operate. As a
battery discharges, the voltage decreases; when
the voltage drops to the FE point, the battery
must be replaced or recharged.
functional test A performance test of a device or
circuit, to see that it behaves as intended in the
environment in which it is to be used.
function generator 1. A signal generator whose
output is any of several selectable waveforms