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.
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.
network
Combination of interconnected components, circuits or systems.
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.
normall 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.
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.
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.
nucleus
Core of an atom. The nucleus contains both positive (protons) and neutral (neutrons) subatomic particles.
