Page 46 - The Illustrated Dictionary of Electronics

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anhysteretic state • anomalous propagation 31

anhysteretic state The condition of a substance anode efficiency Also called plate efficiency. In a
after it has been subjected to a strong magnetic power amplifier using an electron tube, the ratio
field, the intensity of which alternates in direction P o/P i, where P o is the output power in watts and P i
and diminishes gradually to zero. is the dc anode power input in volt-amperes.
animism A belief or philosophy, held especially in anode power input Symbol, P A(input). The product of
Eastern civilizations, such as Japan, that all anode current and anode voltage.
things contain an essence of life. This theory ren- anode power supply The ac or positive dc power
ders irrelevant the question of whether or not ma- supply unit that delivers current and voltage to
chines, such as computers and robots can be the anode of a device.
“alive.” anode saturation The point beyond which a fur-
anion A negative ion. Also see ION. ther increase in anode voltage does not produce
anisotropic Pertaining to the tendency of some an increase in anode current.
materials to display different magnetic and other
physical properties along different axes.
ANL Abbreviation of AUTOMATIC NOISE LIMITER.
anneal To heat a metal to a predetermined temper-
ature and let it cool slowly. The operation pre-
vents brittleness and often stabilizes electrical
characteristics.
annealed laminations Core laminations for trans-
formers or choke coils that have been annealed.
annealed shield A magnetic shield for cathode-ray
tubes, that has been processed by annealing.
annealed wire Soft-drawn wire that has been sub-
jected to annealing.
annotations 1. Marking on copies of original engi-
neering-installation documents to show changes
made during the installation. 2. Any set of com-
ments or notes accompanying a program, an
equipment or system, or a process.
annular 1. Pertaining to the region between two
concentric circles that lie in the same plane; ring-
shaped. 2. Pertaining to two or more concentric
circles that lie in a common plane.
annular conductor A number of wires stranded in
three concentric layers of alternating twists
around a hemp core.
annular transistor A mesa transistor in which the
base and collector take the form of concentric anode strap In a multicavity magnetron, a metal
rings around a central emitter. strap connecting the anodes.
annulling network A subcircuit that shunts a fil- anode terminal 1. In a diode, the terminal to
ter to cancel reactive impedance at the extreme which a positive dc voltage must be applied for
ends of the pass band of the filter. forward bias. Compare CATHODE TERMINAL. 2.
annunciation relay A relay that indicates whether In a diode, the terminal at which a negative dc
or not a circuit is carrying current. voltage appears when the device is used as an ac
annunciator A device that produces loud sound rectifier. Compare CATHODE TERMINAL. 3. The
and/or conspicuous light to attract attention terminal that is connected internally to the an-
(e.g., the electronic siren in an automotive secu- odic element of any device.
rity system). anode voltage Symbol, E A or V A . The difference in po-
anode 1. The positive electrode of a vacuum tube tential between the anode and cathode of a device.
or solid-state device (i.e., the electrode toward anodic Pertaining to the anode of a device, or to
which electrons move during current flow). 2. In anode-like effects.
an electrochemical cell, the electrode that loses anodizing An electrolytic process in which a pro-
electrons by oxidation. This is usually the nega- tective oxide film is deposited on the surface of a
tive electrode. metallic body acting temporarily as the anode of
anode balancing coil Mutually coupled windings the electrolytic cell.
used to maintain equal currents in parallel an- anomalous dispersion Dispersion of electromag-
odes operating from a common transformer ter- netic radiation that is characterized by a decrease
minal. in refractive index with increase in frequency.
anode current Current flowing in the anode circuit anomalous propagation 1. The low-attenuation
of a device. propagation of UHF or microwave signals through