FREQUENCY DEVIATIONRefers to the difference between the carrier frequency of an fm
signal and the instantaneous frequency of its modulated wave.
FREQUENCY DOMAINA plot of frequency versus amplitude as shown by a spectrum
FREQUENCY RESPONSE(I) The ability of a component or device to operate over a portion
of the frequency spectrum. (2) In reference to test equipment, that portion of the frequency
spectrum that the test equipment is capable of sensing and measuring accurately.
GALVANOMETERA meter used to measure small values of current by electromagnetic or
IMPEDANCE ANGLE METERA device that measures circuit impedance by comparing the
phase angle between voltage and current.
INSERTION LOSSThe difference between the amount of power applied to a load before and
after the insertion of a device in the line.
INTEGRATED CIRCUIT (IC)(1) A circuit in which many elements are fabricated and
interconnected by a single process (into a single chip), as opposed to a nonintegrated circuit
in which the transistors, diodes, resistors, and other components are fabricated separately and
then assembled. (2) Elements inseparably associated and formed on or within a single
INTERMODULATION DISTORTIONNonlinear distortion characterized by the appearance
(at the system output) of frequencies equal to the sums and differences of two or more
frequencies present at the input.
LOAD(I) A device through which an electric current flows that changes electrical energy into
another form. (2) Power consumed by a device or circuit in performing its function.
LOGIC CLIPSA device that can be clipped onto an in-circuit, dual-in-line package (DIP)
logic IC to determine the logic state of each pin of the IC.
LOGIC PROBEA hand-held probe used to determine the logic state (high or low) of test
points in a logic circuit. A logic high is represented by a lit indicator light on the probe.
LOGIC PULSERA hand-held probe used to pulse, or change the logic state, of in-circuit logic
METROLOGY CALIBRATION (METCAL) PROGRAMA Navy calibration program
designed to ensure the accuracy of test equipment through comparisons with calibration
laboratory standards of known accuracy.
MICROPHONICSElectrical noise caused by the mechanical motion of the internal parts of a
device. The term is usually associated with vacuum tubes.
MODULATION INDEXWhen a sine wave is used to modulate an fm signal, the ratio of the
frequency deviation to the frequency of the modulating wave.