18WuD2x

254 element • ELSIE
operations, a subunit of a category that cannot
be further categorized [e.g., a bit (word element)
or a record (file element)].
elemental area In a facsimile or television picture,
a scanning line segment as long as the line’s
width.
elemental charge See ELEMENTARY CHARGE.
elemental semiconductor A semiconductor containing
one undoped chemical element.
elementary charge Symbol, e. Also called unit
electric charge. The electric charge of a single
electron or proton. This charge is approximately
equal to 1.6022 × 10 –19 coulomb.
elementary particle 1. A minute charged or uncharged
particle within the atom (i.e., electron,
proton, neutron, quark, etc.). 2. In theory, a subatomic
particle that cannot be broken down into
smaller particles.
element error rate In communications or data
transfer, the ratio n i /n t , where n i is the number of
elements received incorrectly and n t is the number
of elements transmitted.
element spacing 1. The spacing between radiator,
director, and reflector elements in a directional
antenna. 2. The spacing between the internal
electrodes of a vacuum tube.
elevation Angular position (in degrees) of a point
above the horizontal.
elevation-position indicator A type of radar display
simultaneously indicating the elevation of,
and the line-of-sight distance to, the target.
elevator control 1. An electronic system for automatically
stopping an elevator and opening the
doors. Various safety functions are included, an
example being the reopening of a closing door
when a passenger steps into the car. 2. In an aircraft,
the mechanical, electronic, or electromechanical
devices or circuits involved in actuation
of the elevators.
ELF Abbreviation for EXTREMELY LOW FRE-
QUENCY.
eliminator 1. A device or circuit acting as a surrogate
for an inconvenient or undesirable component
(e.g., battery eliminator). 2. A device for
removing or minimizing an undesirable signal or
quantity (e.g., harmonic eliminator); interference
eliminator.
ell A coaxial fitting that is a right-angle line section
with a coaxial connector at each end. It takes its
name from its L shape.
ellipse A geometric figure having the Cartesianplane
formula (x – x 0 ) 2 /a 2 + (y – y 0 ) 2 /b 2 = 1, where
a and b are constants, and x o and y 0 represent
the center point.
elliptical filter See ELLIPTIC FILTER.
elliptical function See ELLIPTIC FUNCTION.
elliptical load line For any amplifier with an output
transformer, a load line in the shape of an ellipse,
obtained when the load connected to the
output element is reactive, rather than purely resistive.
elliptically polarized wave An electromagnetic
wave in which the rotation of the electricintensity
vector at one point describes an ellipse.
elliptical orbit A satellite orbit that is not a perfect
circle. In theory, all satellites deviate slightly from
perfectly circular orbits. Sometimes a satellite is
deliberately put into an orbit that is greatly elongated.
The closer the satellite is to the earth, the
faster it moves.
elliptical polarization Polarization characterized
by elliptical rotation of the wave vector at a given
point.
elliptical stylus In a phonograph (turntable) system,
a stylus with a characteristic ellipsoidal
shape.
elliptic filter A band-pass, band-stop, high-pass,
or low-pass inductance-capacitance (LC) filter,
designed according to an ELLIPTIC FUNCTION.
Characterized by a steep attentuation-versusfrequency
cutoff response with ripple in both the
passband and the stopband.
elliptic function A function, similar to the
Chebyshev and Butterworth functions, used in
the design of certain selective filters. The elliptic
function results in a better filter magnitude response
than the Chebyshev or Butterworth
functions in some applications. See ELLIPTIC
FILTER.
elongation
A form of modulation distortion resulting
from multipath propagation. Some of the
paths result in greater propagation delay than
other paths; this causes the modulation envelope
to spread out. The higher the modulating frequency,
the greater the effect.
ELSE
y o
y
ellipse
A word used in a BASIC computer program
that provides an instruction based on a relational
test and, in this respect, is related to IF-THEN,
ON-GOTO, etc. It specifies the operation to be
done if the conditions given in the same program
line don’t occur.
ELSIE Abbreviation of electronic letter-sorting and
indicator equipment.
x o
a
x
b