V (abbreviation) See volt.
Vac (abbreviation) Volts, alternating current.
vacuum evaporation (process/IC) A process for generating thin films, in which the film material is vaporized and the vapor deposits itself, through openings in a mask, onto a substrate.
variable (general) A quantity that can assume any of a given set of values.
Vdc (abbreviation) Volts, direct current.
VDE - Verband Deutscher Elektrotechniker. The Association of German Electrical Engineers. German standards writing and testing agency.
Velocity of
Propagation
--The speed
with which a signal wave travels
through a particular transmission medium. It varies as follows:
Medium Speed, miles per second
Light through space 186,284
Radio through air 142,000
Coaxial cable 133,000
Very High Frequency (VHF)--A Federal Communications Commission designation for the band from 30 to 300 MHz on the radio spectrum.
VHDCI--Very High Density Cable Interconnect (0.8mm connector) for next generation Ultra-SCSI applications.
VHSIC (abbreviation) Very high speed integrated circuit. A Department of Defense program to develop exceptionally fast ICs.
vibration (measurement) (1)A continuously reversing change in the magnitude of a force. (2)A mechanical motion or oscillation about a given point of equilibrium.
vinyl (material) A form of plastic used as insulation, which has high dielectric strength and low water absorption.
viscosity (property) The measure of the resistance of a fluid to flow (either through a specific orifice or in a rotational viscometer). The absolute unit of viscosity measurement is the poise (or centipoise). Kinematic viscosity is expressed in strokes.
Voice-Frequency (VF)--Any frequency within that part of the radio frequency range essential to speech transmission of a commercial quality (i.e., 300 to 3400 Hz). Also referred to as telephone frequency.
Volt (V)--The unit of measurement for electromotive force (emf). It is equivalent to the force required to produce 1 ampere through a resistance of 1 ohm.
Voltage
- The term most often used in place of electromotive force, potential,
potential difference, or voltage drop to designate the electrical pressure
that exists between two points and is capable of producing a current when a
closed circuit is connected between two points.
Voltage Drop--The
voltage developed across a component or conductor by the flow of current
through the resistance or impedance of that component or conductor.
Voltage Rating --The highest voltage that may be continuously applied to a wire in conformance with standards or specifications.
voltage regulator (circuit) A circuit capable of generating from a varying input voltage a constant output voltage to a varying load current.
VSWR--Abbreviation for voltage standing wave ratio. Also see: standing wave ratio.
vulcanization (process) A chemical reaction in which the physical properties of an elastomer are changed by reacting it with sulfur or other cross-linking agents.
VW-1 - A flammability rating established by Underwriters' Laboratories for wires and cables that pass a specially designed vertical flame test, formerly designated FR-1.