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NAND.
A logic function of A and B that is true if either A or
B is false.
NAND CIRCUIT.
A combination of a NOT function and an AND
function in a binary circuit that has two or more inputs and one
output. The output is logic 0 only if ALL inputs are logic 1; it is
logic 1 if ANY input is logic 0.
NATURAL HORIZON.
The line-of-sight horizon.
NEAR SYNCHRONOUS ORBIT.
An orbit in which the satellite
rotates close to but not exactly at the same speed as the earth.
NEGATION.
The process of inverting the value of a function or
variable.
NEGATIVE ALTERNATION.
That part of a sine wave that is below
the reference level.
NEGATIVE CLAMPER.
A circuit that clamps the upper extremity
of the output waveshape to a dc potential of 0 volts.
NEGATIVE ELECTRODE.
A terminal or electrode having more
electrons than normal. Electrons flow out of the negative terminal
of a voltage source.
NEGATIVE FEEDBACK.
Feedback in which the feedback signal is
out of phase with the input signal. Also called DEGENERATIVE
FEEDBACK.
NEGATIVE LOGIC.
The form of logic in which the more positive
voltage level represents a logic 0, FALSE, or LOW and the more
negative voltage represents a logic 1, TRUE, or HIGH.
NEGATIVE-RESISTANCE ELEMENT.
A component having an operating
region in which an increase in the applied voltage increases the
resistance and produces a proportional decrease in current. Examples
include tunnel diodes and silicon unijunction transistors.
NEGATIVE TEMPERATURE COEFFICIENT.
A characteristic of a
semiconductor material, such as silver sulfide, in which resistance
to electrical current flow decreases as temperature increases.
NETWORK.
A combination of electrical components. In a
parallel circuit it is composed of two or more branches
- Negative feedback
-
A feedback signal 180° out
of phase with an amplifier input signal. Used to increase
amplifier stability, bandwidth and input impedance. Also reduces
distortion.
- Negative ground
A system where the negative
terminal of the source is connected to the system's metal chassis.
- Notch filter
A filter which blocks a
narrow band of frequencies and passes all frequencies above and
below the band.
- Npn transistor
A bipolar junction
transistor in which a p-type base element is sandwiched between an
n-type emitter and an n-type collector.
- Nucleus
Core of an atom. The
nucleus contains both positive (protons) and neutral (neutrons)
subatomic particles
- N-type semiconductor
A semiconductor compound
formed by doping an intrinsic semiconductor with a pentavalent
element. An n-type material contains an excess of conduction band
electrons.
- Negative
Terminal that has an excess
of electrons.
- Negative charge
A charge that has more
electrons than protons
- Negative ion
An atom having a greater
number of electrons in orbit than there are protons in the
nucleus.
- Negative resistance
A resistance such that when
the current through it increases the voltage drop across the
resistance decreases.
- Negative temperature coefficient
A term used to describe a
component whose resistance or capacitance decreases when
temperature increases.
- Neon bulb
Glass envelope filled with
neon gas which when ionized by an applied voltage will glow red.
- Neutral
A terminal, point or object
with balanced charges. Neither positive or negative.
- Neutral atom
An atom in which the number
of negative charges (electrons in orbit) is equal to the number of
positive charges (protons in the nucleus).
- Neutral wire
The conductor of a
polyphase circuit or a single-phase three wire circuit that is
intended to have a ground potential. The potential difference
between the neutral and each of the other conductors are
approximately equal in magnitude and equally spaced in phase.
- Neutron
Subatomic particle in the
nucleus of an atom and having no electrical charge.
- Nickel-cadmium cell
A secondary cell that uses
a nickel oxide positive electrode and a cadmium negative
electrode.
- Node
Junction or branch point in
a circuit.
- Noise
Unwanted electromagnetic
radiation within an electrical or mechanical system.
An operational amplifier
circuit having no phase inversion between the input and output.
- Non-inverting input
The terminal on an
operational amplifier that is identified by a plus sign.
- Non-linear scale
A scale in which the
divisions are not equally spaced.
- Normal closed
Designation which states
that the contacts of a switch or relay are closed or connected
when at rest. When activated, the contacts open or separated.
- Normally open
Designation which states
that the contacts of a switch or relay are normally open or not
connected. When activated the contacts close or become connected.
- North pole
Pole of a magnet out of
which magnetic lines of force are assumed to originate.
- Norton's theorem
Any network of voltage
sources and resistors can be replace by a single current source in
parallel with a single resistor.
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