Potentiometer: A three-terminal variable resistor. Two terminals connect to the ends of a flat resistor, while the third terminal is attached to a moveable contact that interfaces with the resistive element. The moveable terminal, or slider, is capable of being positioned from one end of the element to the other. There are many physical types, with the rotary design being the most common, followed by linear slider used in graphic equalizers, for example. Often used as voltage dividers in electronic circuits, the input voltage is applied to the top of the resistive element, while the other end is tied to ground or a common reference and the output is taken from the slider. When the slider is positioned to the top extreme, the output equals the input less of course, the effect of the resistor, moving it to the bottom extreme gives an output of zero volts; and every possible level between is available as the slider is moved from one end to the other. The most commonly encountered application of this arrangement to control the volume of an audio device. In this way the electrical potential is varied, hence, a potentionmeter. The rate at which the voltage changes as the slider is moved is controlled by the taper of the pot. The taper defines the amount of resistive change as a function of travel.

 

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Potentiometer: A three-terminal variable resistor. Two terminals connect to the ends of a flat resistor, while the third terminal is attached to a moveable contact that interfaces with the resistive elemen . . . View Full Definition

Vco (Voltage Controlled Oscillator): An oscillator whose frequency output is controlled by varying its voltage rather than with a potentiometer.

Vcf (Voltage Controlled Filter): An audio filter whose effective frequency band is controlled by varying its voltage rather than with a potentiometer.

Vca (Voltage Controlled Amplifier): An amplifier whose output is controlled by varying its voltage rather than by direct resistance (as with a potentiometer).