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TRIATIC—A special type of monopole antenna array [17].
TRIGGER—A short pulse, either positive or negative, that can be used to cause an electronic function to
take place [9].
TRIGGER GENERATOR—See SYNCHRONIZER [18].
TRIGGER PULSES—In radar, pulses that are used to initiate specific events [18].
TRIODE TUBE—A three-electrode electron tube containing a plate, a cathode, and a control grid [6].
TRIP-ELEMENT—The part of a circuit breaker that senses any overload condition and causes the circuit
breaker to open the circuit [3].
TRIP-FREE CIRCUIT BREAKER—A circuit breaker that will open a circuit even if the operating
mechanism is held in the ON position [3].
TRIVALENT IMPURITY—Acceptor impurities containing only three valence electrons [7].
TROPOSPHERE—The portion of the atmosphere, closest to the earth's surface, where all weather
phenomena take place [10].
TROPOSPHERIC SCATTER—The propagation of radio waves in the troposphere by means of scatter
[10].
TROUBLE INDICATORS—Signal lights used to aid maintenance personnel in locating troubles quickly
[15].
TROUBLESHOOTING—The process of locating and diagnosing faults in equipment by means of
systematic checking or analysis [3] [15] [16].
TROUBLE TABLES—Tables of trouble symptoms and probable causes, furnished by many manufacturers
to help technicians isolate problems [15].
TROUGH (BOTTOM)—The peak of the negative alternation (maximum value below the line) of a sine
wave [10].
TRUE BEARING—Angle between a target and true north measured clockwise in the horizontal plane [18].
TRUE NORTH—Geographic north [18].
TRUE POWER—The power dissipated in the resistance of the circuit, or the power actually used in the
circuit [2].
TRUNCATED PARABOLOID—A paraboloid reflector that has been cut away at the top and bottom to
increase beam width in the vertical plane [18].
TRUTH TABLE—A table that describes a logic function by listing all possible combinations of input
values and indicating, for each combination, the true output values [13].
TUBE DYNAMIC CONDITION—Refers to the testing condition in which a vacuum tube is actually
performing its function [16].
TUBE STATIC CONDITION—Refers to the testing condition in which a tube has certain voltages applied
but is not in its normal operating condition [16].
