V

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V

Volt : (V) The unit of electric potential difference (Voltage) between two points.

VA : Volt Amperes - measure of apparent power.

VAC : Volts Alternating Current.

Vacuum Tube : (Also known as an Electron Tube or a Thermionic Valve). A device that creates or modifies an electrical signal through the movement of electrons in a low pressure (vacuum) space.

Varactor Diode : a component whose capacitance decreases as the reverse bias voltage is increased.

VCO : Voltage-controlled oscillator

VE : Volunteer Examiner, in countries in which government radio inspectors no longer conduct examinations for prospective new licensees but delegate this task to a few experienced radio amateurs. (Also: VE as a callsign prefix refers to the Dominion of Canada - so "W/VE stations" would indicate the continent of North America.)

VEC : Volunteer Examiner Coordinator

Vertical Polarization : Used to describe a transmission or antenna in which the electric field is propagated perpendicular to the surface of the Earth. Antennas intended for two-way radio communication with mobile stations (where vertical antennas are common) typically use vertical polarization, while broadcast TV/FM signals are most often horizontally polarised.

VFO : Variable Frequency Oscillator

Velocity Factor : the speed at which radio waves travel in a particular feedline, expressed as a fraction of the speed of light

VHF : Very High Frequency. Frequencies in the range 30MHz to 300MHz

VIS : Vertical Interval Signalling. Digital encoding of the transmission mode in the vertical sync portion of an SSTV image.

VLCA : Very limited coverage area. Typically used in reference to small portable repeaters deployed by emergency/disaster or public service groups to temporarily provide local communication within a relatively-small area.

VLF : Very Low Frequency 3 - 30 KHz

VMOS : Vertical metal-oxide semiconductor

VOX : Voice Operated Transmit

VSWR : Voltage standing wave ratio

VK : Australia

VXO : Variable crystal oscillator

VY : CW abbreviation for "very"