V

  1. Symbol for voltage or volts.
  2. Varnished cambric insulation with fibrous covering.

V Connector

A connector that joins two branch conductors to a main conductor.

VA

Volt Ampere. A designation of power in terms of volts and amperes.

Vacuum Tube

See Electron Tube.

VAFC

VESA Advanced Feature Connector. A standard that specifies 80-circuit vertical and right-angle plugs and 80-circuit IDT receptacles.

Value Added

A term used to describe custom assemblies, such as IDC flat cable connectors and ribbon cable.

Vapor Phase

Method of simultaneously soldering variously configured component parts. The process is carried out in a specially equipped chamber. The high temperature vapor of a boiling fluorinated hydrocarbon serves as the heat transfer medium. Secondary vapors minimize thermal shock as the PCB enters/returns to ambient temperature.

VCB

Varnished cambric insulation, cotton braid, flame retarding, moisture resisting finish.

VCL

Varnished cambric insulation, lead covered cable. Ends hermetically sealed.

VD

Twin wire that has two types of conductors under an outer fibrous covering

Velocity of Propagation

The absolute transmission speed of a signal through a dielectric core of a transmission line, a property of the material dielectric with dimensions of length/unit time.

See also Reactive Velocity of Propogation.

Vertical

A connector mounting configuration option. Also called straight.

Vertical, Direct Mounting

A terminal block mounting configuration. Frequently used on PCBs when solder connections are used to fasten the block to the board.

Vertical, End Position Mounting

A terminal block mounting configuration used where end sections are needed for mounting.

Very High Density Cabled Interconnect (MOD P4)

An 0.8 mm pitch shielded I/O system.

Very High Frequency (VHF)

See VHF.

Very Short Line

Negligible interconnect "size" or length which can be effectively ignored in Signal Line Analysis.

VESA

Video Electronics Standards Association. A US-based organization that sets standards for the interface between graphics and video subsystems in PCs and other computing environments.

VG

Varnished glass tape over a flexible copper conductor. Varnished glass or nylon braid, 600 in or 3000 in, 130° C.

VGA

Video Graphics Array. Describes the resolution of video display devices. VGA refers to a resolution of 640x480 pixels.

VHDCI (MOD P3)

Very High Density Cabled Interconnect

VHF

Very High Frequency. The band of frequency that extends from 30 to 300 mHz, as designated by the Federal Communications Commission.

VIA Hole

A plated through-hole used as a through connection, but in which there is no intention to insert a component lead or other reinforcing material.

Vibrobot Line Plating

A terminal plating process mainly used for overall gold plating of loose pins/terminal. It is sometimes used to plate overall tin on long pins to prevent damage during the barrel plating.

The process is the reverse of barrel plating, in which the pins/terminals stay in a fixed container and solutions are poured in one after another based on a pre-set program.

VITA

VMEbus Manufacturers Group (ANSI accredited)

VL Bus

  1. A local bus standard, developed by VESA, for connecting devices to a CPU. The VL-Bus standard specifies a 16-bit Micro Channel Connector. VL bus is a computer system architecture bus standard for the PC market. The standard includes a definition of a board-to-board mating interface between the motherboard and PC add-on cards.
  2. A 32-bit data bus architecture developed by VESA for transporting a high bit stream video data.

VLF

Very Low Frequency. The frequency band that extends from 10 to 30 kc, as designated by the Federal Communications Commission.

VLPR

Very Low Profile

VLSI

Very Large Scale Integration. A single monolithic integrated circuit that contains an electronic circuit or system that has a minimum of 10,000 transistors or logic gates per silicon chip.

VM

Designation for cable that has conductors twisted together under an outer fibrous covering.

VME Bus

Versa Module Europe. A bus architecture developed in 1981.

VoB

A Technology application for broadband networks that allow multiple lines of POTS-quality voice over the same pipe that is delivering high-speed data.

See also Base Station Controller.

Void

A holes in a header that does not have a pin/terminal. This could be for cost saving (why put a contact if it is not going to be used?) or for polarization purposes. Note that not all assembly machines can assemble connectors with voids. Zipper and gang machines cannot do so.

Volatile Memory

Any type of memory not capable of retaining the information stored without a continuous power supply. Volatile memory is erased when the power supply is shut off.

Volt (V)

The unit of measure of electromotive force. It is equivalent to the force required to produce a current of one ampere through a resistance of one ohm.

Voltage Breakdown

The maximum voltage on insulated wire before electrical current leaks through the insulation.

Voltage Drop

The voltage developed across a component or conductor by the current in the resistance or impedance of the component or conductor.

Voltage Rating

  1. The maximum voltage that can be safely applied to a component (such as a terminal in a plug or receptacle) without danger of breakdown.
  2. The maximum AC or DC voltage that a switch can be expected to break continuously during its rated operating life.

Volt-Ohm-Meter

An instrument, with several ranges, used to measure voltage, resistance, and current.

VOM

See Volt-Ohm-Meter.

Vp

Signal Velocity of Propagation. An absolute term for velocity of a signal in a given transmission line material medium (meters/nanosecond).

See also vp.

vp

Relative Signal Velocity of Propagation. Measurement to equate the speed of a transmission line relative to the speed of light in a vacuum or air as a percentage.

See also Vp.

VR

Voltage Regulator

VRAM

Video Random Access Memory

VSWR

Voltage Standing Wave Ratio

See also Standing Wave, Standing Wave Ratio.

VTVM

Vacuum Tube Volt Meter. An instrument, with vacuum tube amplifiers, used to measure voltage, resistance, and current.