V: Difference between revisions

From Amateur Radio Wiki
Jump to navigation Jump to search
(added vy)
 
(5 intermediate revisions by 2 users not shown)
Line 8: Line 8:


'''VAC''' : Volts Alternating Current.
'''VAC''' : Volts Alternating Current.
'''[http://en.wikipedia.org/wiki/Vacuum_tube 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.
'''Varactor Diode''' : a component whose capacitance decreases as the reverse bias voltage is increased.
Line 15: Line 17:
'''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_database#Callsign_prefixes_by_Prefix | callsign prefix]] refers to the Dominion of Canada - so "W/VE stations" would indicate the continent of North America.)
'''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_database#Callsign_prefixes_by_Prefix | callsign prefix]] refers to the Dominion of Canada - so "W/VE stations" would indicate the continent of North America.)


'''VE''' : Volunteer Examiner Coordinator
'''VEC''' : Volunteer Examiner Coordinator


'''Vertical Polaraization''' : Used to describe a transmission or antenna in which the electric field is propagated perpendicular to the surface of the Earth.
'''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 antenna]]s are common) typically use vertical polarization, while broadcast TV/FM signals are most often horizontally polarised.


'''VFO''' : Variable Frequency Oscillator
'''VFO''' : Variable Frequency Oscillator


'''Velocity Factor''' : the speed at which radio waves travel in a particular [[Feedlines | feedline]], expressed as a percent of the speed of light
'''Velocity Factor''' : the speed at which radio waves travel in a particular [[Feedlines | feedline]], expressed as a fraction of the speed of light


'''[[VHF]]''' : Very High Frequency. Frequencies in the range 30MHz to 300MHz
'''[[VHF]]''' : Very High Frequency. Frequencies in the range 30MHz to 300MHz
Line 36: Line 38:


'''VSWR''' : Voltage standing wave ratio
'''VSWR''' : Voltage standing wave ratio
'''VK''' : Australia


'''VXO''' : Variable crystal oscillator
'''VXO''' : Variable crystal oscillator
'''VY''' : CW abbreviation for "very"

Latest revision as of 03:05, 29 January 2011

A B C D E F G H I J K L M N O P Q R S T U V W X Y Z 0 - 9

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"