Amateur radio terminology is the term used by radio amateurs
for radio communication. It is a language spoken by amateur radio operators
over the radio. Some of these amateur radio operating procedures have much more
in common with the other radio services. These are radio jargon used for easy
facilitation of the message across various operators from different
backgrounds, experiences, and locations. It also facilitates efficient and
effective world wide amateur radio communication despite language and other
barriers. Most of these words are used to describe technical data related to
amateur radio operation while others are slang used by radio operators.
This list has been an ever increasing one with a number of
terms being added over time for various purposes.
A
AC : Alternating Current
ADC : Analogue to Digital Converter. Also known as A/D
and A-to-D. A device that samples an analogue wave and converts it into a
digital signal, in which a series of numbers is used to represent the amplitude
of the original wave.
ADIF : Amateur Data Interchange Format, a standard
specification for format of exported logbook files.
A/D - Analog-to-Digital
Aerial - Used in the early days of radio - sometimes
referring to an outdoor antenna. Still used in the UK.
Admittance : The reciprocal of impedance of a
component in a series or parallel tuned circuit.
AF : Abbreviation for Audio Frequency. AF is in the
range 20Hz to 20 000Hz. Also abbreviation for Africa.
AFC : Automatic Frequency Control - used to prevent
drift in FM receivers
AFSK : Audio Frequency Shift Keying.
AGC : Automatic Gain Control - a feedback system to
reduce fading by automatically adjusting gain
AGL : (Height) Above Ground Level, for antenna
installations.
ALC : Automatic Level Control - a feedback system in the
transmitter output amplifier used to prevent overload.
Ampere :(A) The unit used for measurement of current.
Usually abbreviated to Amps
Amplitude : the height of a wave from the average or
median position.
Amateur radio : A non-commercial radio service as set by a
recognized cognizant government agency.
Amateur radio operator : A person licensed to operate in the
amateur bands.
Amateur service: A radio communication service for the
purpose of self-training, intercommunication and technical investigations
carried out by amateurs, that is, duly authorized persons interested in radio
technique solely with a personal aim and without pecuniary interest.
AMSAT : The name for amateur
radio satellite organizations world-wide, but in particular the Radio
Amateur Satellite Corporation.
AM : Amlpitude Modulation
Amplifier : A device that is used to increase voltage,
current or power.
AMTOR : A specialised form of RTTY protocol. An acronym
for AMateur Teleprinting Over Radio or AMateur Teletype over Radio.
AMSAT : Radio Amateur Satellite Corporation.
Analog (also analogue): a continuously varying signal.
ANC, ANR : Active noise control, active noise
reduction. Also referred to as automatic noise cancellation or antinoise on
some transceivers.
ANARC : Association of North American Radio Clubs.
Antenna : A device to either radiate radio signals or to
receive them from another station.
Antenna Switch : A switch used to change the output of a
transceiver from one antenna to another.
Antenna Tuner : A device used to match the
output impedance of a transmitter to that of an antenna.
Antenna farm : Ham's dream - lotsa room for big, long,
antennas.
Anti-VOX : Transceiver circuitry used in voice-operated
(VOX) stations to prevent audio from the receiver's speaker from actuating the
voice-operated transmitter.
APRS : Automatic Position Reporting System, Automated
Packet Reporting System.
Appliance operator : Hams who neither build nor
experiment with radio equipment, but merely operate commercial equipment,
perhaps without understanding how it all works.
ARC : Amateur Radio Club (also ARA, ARS -
Amateur Radio Association, Amateur Radio Society) - usually prefixed by the
name of the community or region served
ARDF : Amateur Radio Direction Finding
ARES : Amateur Radio Disaster Services, Amateur Radio
Emergency Services
ARRL : The American Radio Relay League - the national
ham radio association for the USA
ARISS : Amateur Radio on the International Space
Station. A program that allows schools, with the help of an amateur club, to
contact the amateur station on board the International space station.
ARQ : Automatic repeat request used in AMTOR.
ASCII : American Standard Code for Information Interchange.
The ASCII 7-bit code represents 128 characters including 32 control characters.
ASR : Automatic send-receive. An RTTY terminal mode that
allows message composition while receiving text from the another station.
ASL : Above Sea Level. Vertical height
in metres or feet above sea level.
Attenuator : A resistive device to reduce the amplitude
or power of a signal.
ATS : Automatic Transfer Switch, switches equipment to
a backup power supply in event of power failure.
ATT : Attenuator, often expressed in dB of reduction.
ATV : Amateur Television - "moving picture"
ham TV transmissions.
Az/El : used to describe an antenna rotator that can
change both the Azimuth (horizontal) and the Elevation (vertical)
direction of the antenna.
Azimuth : The horizontal direction (angle) measured
clockwise from North.
AVC : Automatic Volume Control - A feedback scheme to level
out the receiver audio volume.
AWG : American Wire Gauge - standard for describing the
diameter of wire by which the wire size increases as the gauge number
decreases.
B
Balun : A passive electronic device that converts
between balanced and unbalanced electrical signals using some form of
electromagnetic coupling.
Battery : In early radio,
batteries were the prime source of power - The A battery provided the filament
voltage, the B battery furnished the B+ or the Voltage to the plates of the
tubes, and the C battery provided the grid-bias voltage to the tubes.
Balanced Line : parallel conductors at equal and
opposite potentials. Neither conductor is at ground potential.
Balanced modulator : A mixer circuit used in a
single-sideband suppressed-carrier transmitter to combine a voice signal and
the RF carrier. The balanced modulator isolates the input signals from each
other and the output, so that only the sum and the difference of the two input
signals reach the output. The original carrier signal and the audio signal are
suppressed.
Balun - Balance to unbalance, a device used to couple a
balanced antenna to an unbalanced feed line (e.g., dipole to coax)
Bandpass(also Passband): The range of frequencies that a
certain filter allows to pass.
Base : A radio station located at a fixed location as
opposed to a mobile. Used to identify the control location in a network of
radio stations.
Barefoot - transmitting with a transceiver alone and no
linear amplifier
Base loading - A loading coil at the bottom of an
antenna to achieve a lower resonant frequency.
Base Station : A ham station that has a fixed location.
Bandpass Filter : a filter designed to pass a certain
range of frequencies.
Band : The portions of the Electromagnetic Spectrum
that are allocated to ham radio operators.
Baud : The rate of transmission - in symbols per
second, of digital data. The number of times a transmitted digital signal
changes per second. In the one special case where data is transmitted one bit
at a time serially, the baud rate will match the bps rate.
BBC : British Broadcasting Corporation.
BBS : Bulletin Board System
BCI : Broadcast radio interference.
Beam - an antenna that gives a directional beam
pattern.
Beacon : A station that transmits signals either
continuously or on a timed basis, for location and propagation purposes.
BFO : Beat Frequency Oscillator. An oscillator that is
mixed with an incoming signal at the detector to produce an Audio Frequency
(AF) tone for CW reception. In SSB operation, the beat frequency oscillator
must replace the carrier which was suppressed when the signal was originally
transmitted.
Bird : Slang term for an amateur or communications
satellite.
Birdie : Spurious signals produced in a receiver - usually a
product of mixed intermediate frequencies within the radio.
Bleed over : Interference caused by a station operating on
an adjacent channel
Bleeder resistor : A large-value resistor connected across
the filter capacitor in a power supply to discharge the filter capacitors when
the supply is turned off.
Block diagram : A drawing using rectangles to represent
major sections of electronic circuits. The diagram shows signal flow and the
function of the sections.
Boat Anchor : A slang term used to describe obsolete
ham radio gear - often applied to old transceivers.
Bon jour: Good morning (French)
Bon soir: Good evening (French)
Bootlegger : Someone, usually not a Ham but a wannabe,
making up a callsign, one usually not in the callbook, and getting on the air.
Sometimes it is someone who already bought a radio, took the test and flunked,
and then gets on the air anyway.
Bounce : Reflections of a radio wave off of an object,
(e.g., the ionosphere or the moon)
Boat anchor : Antique ham equipment -- So named because of
weight and size.
BNC : A push-and-turn locking coaxial connector
commonly used with VHF/UHF transceivers, as well as oscilloscopes and
test equipment. Bayonet Niell-Concelman (standard connector type used on COAX
cable, named for its inventors).
BPS : Bits per second, the rate at which digital data
is transmitted. The number of characters transmitted per second will be a
sub-multiple of this figure (for instance, if a character is sent with 8 data
bits, 1 start bit, 1 stop bit, the number of actual characters transmitted per
second would be one tenth the bps rate).
BPL : BroadBand Over Power Lines
BPSK : (Binary Phase Shift Keying). A digital
modulation method for transmitting data. Digital DSB suppressed carrier
modulation.
Breadboard : Early experimenters used a wood board or bread
board to lay out circuits. Now used to describe an experimental layout on
whatever media -- like PC boards.
Break : (Repeater Term) used to interrupt a conversation on
a repeater to indicate that there is an emergency or urgent message. If
non-urgent, simply interject your callsign.
Break break : (Repeater Term) used to intercede in an
existing conversation with emergency communications.
broadcasting: transmissions intended for the general
public. Broadcasting is prohibited on the Amateur Radio Bands, other than QST's
which of are of interest to all Amateur Stations, example W1AW code practice
transmissions.
Bug : A semi-automatic mechanical code key
Breaker: A radio amateur who wants to join a contact that is
already in progress.
Buffer Amplifier : An amplifier usually attached to an
oscillator so as to reduce the drain on the oscillator output.
Bureau (also Burro) : An International Amateur
organization set up to process QSL cards between amateurs. Provides an
inexpensive way to send and receive QSL cards.
Busted Call : An incorrectly logged callsign.
C
Callsign : A unique identifier for each radio amateur and
licensed radio station throughout the world.
Call book : A publication or CD ROM that lists licensed
amateur radio operators.
Calling frequency : A defacto standard frequency where
stations attempt to contact each other.
Candy store : Term for the local Ham Radio Dealer.
Cans : Headphones
Cap : Capacitor (formerly condenser)
Capacitor : A passive electronic component composed of
two conducting plates separated by a dielectric (insulating material).
Capacitive Hat : Also known as a capacity hat. A system
of wires, or at VHF and above a solid metal disk, added to the top of
a vertical antenna to reduce its inductance and increase
its bandwidth.
Carrier : A pure continuous radio emission at a fixed
frequency, without modulation and without interruption. Several types of
modulation can be applied to the carrier, See AM and FM.
Carrier Frequency : The centre frequency of a radio
signal.
Carrier Power : The average power supplied to the
antenna when no modulation is taking place.
Carrier-operated relay (COR) : (Repeater Term)
circuitry that causes the repeater to transmit in response to a received
signal.
Cavity filter : A very narrow RF filter used to pass
one single frequency, common in repeater operations where the receiver must be
protected from overload by a transmitter on the same band on the same antenna
tower.
Circular Polarization: A method of polarizing the antenna
such that the emmitted electric field rotates around the axis of the antenna
CLOVER : A PSK mode that allows full duplex
communications.
CNDX : Abbreviation for Conditions
Coaxial Cable : Cable that has a central conductor and
an outer shield as the second conductor. Known as coaxial because the cable is
cylindrical and the conductors share the same central axis.
Color Code : Also spelt colour code. Coloured bands on
resistors and other components that show their value.
Condenser : old name for Capacitor
Conductor : A material through which electricity flows
easily.
Core : The material used in the centre of
an Inductor coil.
CQ : Request for contact - specifically "calling
any operator"
CQ Magazine : Published by CQ Communications.
Cross Modulation : distortion caused by two or more carriers
interfering with each other.
CTCSS : Continuous Tone-Coded Squelch System
- a sub-audible tone that is frequently used on repeaters. The signal
"opens" the repeater for use.
Current : The flow of electricity through a conductor -
usually associated with electron movement, but current is actually the transfer
of charge between atoms.
CW : Continuous Wave - used in Morse
code transmissions.
CW Abbreviations Used by CW operators to reduce the
length of transmissions by shortening words or phrases to a 2 or three letter
code.
D
DAC : Also known as D/A and D-to-A. Digital to Analogue
converter. A device that converts digital signals into analouge signals.
dB : Decibel - the ratio of two power
measurements.
dBd : dB relative to a dipole. Also known as dBD
dBi : dB relative to a theoretical isotropic (point)
source.
dBm: The power compared to a 1 milliwatt (1mW) source,
expressed in decibels (dB)
dBo : Optical gain. An unofficial term used by some
amateurs working with transmission of data using light.
dBuv : a measure of voltage compared to one microvolt.
0dBuv = one microvolt.
De or DE : "this is" or "from" -
for example an operator may use VL2TK de VK4ZW .......
DF : Direction finding. Also known
as ARDF and "fox hunting", the use of triangulation and
directional antennas to find a hidden transmitter. May be done recreationally,
or as a means of locating the source of problematic radio frequency
interference.
Diplexer : A frequency splitting device used to couple
two transceivers to either a single antenna or a dual band antenna.
Dipole : An antenna with two collinear elements,
usually of equal length, with feedpoint in the centre. Commonly used as the
driven elements for more complex antennas such as the yagi or log-periodic, a
dipole on its own is omnidirectional if mounted for vertical
polarisation but has a figure-8 directional pattern if mounted
horizontally.
Dish : A highly directional antenna, parabolic in
shape. Often used at microwave frequencies.
Domino EX : a digital mode that uses a
variant of MFSK known as IFK for transmission of information.
Downlink : The channel or frequency used
for satellite to earth communications.
Do Svidaniya: Good bye (Russian)
DPSK : Differential Phase Shift Keying
- a form of BPSK
DRM : Digital Radio Mondiale. A system of digital
broadcasting developed by a consortium of manufacturers, researchers,
broadcasters and governments.
DSP : Digital Signal Processing. The
digital processing of signals in filtering, noise reduction etc.
DTMF Dual Tone Multi Frequency - the allocation of a
unique tone pair to each button on an appliance (made up of two frequencies -
high and low) that allows a computer to recognize the tone. Originally used on
a wide scale in landline telephony to allow tone dialling using a small keypad
on a telephone or handset, but has been used in amateur radio to remotely
control repeaters, autopatch, IRLP or Echolink nodes.
Dual Band Antenna : An antenna designed to be used on
two amateur Bands.
Dummy Load : An artificial antenna that does
not radiate. A non-inductive power resistor, a dummy load is connected in place
of the transmitting antenna and used when aligning transceivers.
Duplex : Transmit and receive are on two different
frequencies - often use in repeaters with a shift (difference) of 600Hz.
Duplexer : A device that allows an antenna to transmit
and receive simultaneously.
DVM : Digital voltmeter.
DXCC : DX Century Club
DX : Distance or distant station. Originally
"distant exchange", from landline telephony. On HF radio, normally
used to refer to a station on another continent or in an exotic location.
DXpedition : An expedition by amateurs to a location
that may be geographically or physically remote and from where amateur contacts
are rare.
Dynamic
Range : How well a
receiver can handle very strong signals wthout overloading.
E
Earth : A circuit connection to a ground rod driven
into the ground or system of wires buried below the surface of the ground.
EIRP : Effective Isotropic Radiated Power.
The sum of transmitted power and antenna gain, minus any transmission line
losses.
Electromagnetic Waves : The waves emitted by
an antenna, having two dimensions, electric and magnetic.
EHF : Extremely High Frequency - from
30GHz to 300GHz
Electron Tube : (Also known as an Vacuum
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.
Elevation (1) : The angle that an antenna - often
a beam - makes with the horizontal.
Elevation (2) : How high an object/place/station
is above sea level. Same as ASL (Above Sea Level)
Elmer : Slang for a person who helps newcomers get
started in amateur radio.
EME : Earth Moon Earth - bouncing a
signal off the moon to a remote station that would not normally be accessible.
EMF : Electromotive Force - Voltage.
EMI : Electromagnetic Interference.
ERP : Effective Radiated Power.
Eyeball QSO: Meet someone in person.
eQSL : Electronic QSL - a website for sending
and receiving QSL's online.
E-Skip : Propagation through signals being
refracted in the E-Layer
Eu : Europe
F
FCC : Federal Communications Commission.
The US
government body that regulates the use of the radio spectrum.
F/D : The ratio of focal length to diameter of
a parabolic dish antenna.
Feedline : The wire or cable that joins a transmitter or receiver to
an antenna. Also known as a transmission line.
FET : Field-effect transistor, a semiconductor in which
current between source and drain is controlled by voltage applied to a
high-impedance gate
Field day : An annual event in which portable stations
are deployed, contacts made and new or prospective operators encouraged to get
on the air.
Field Strength Meter : A devie used to measure the
strength of an electromagnetic field.
Filter : An electric circuit (often called a network)
that allows certain frequencies to pass but rejects (attenuates) other unwanted
frequencies.
FM (Frequency Modulated or Frequency Modulation): The
frequency of the carrier signal is changed (modulated) in direct proportion to
the instantaneous amplitude of an input signal, usually the voice of the
operator. The resulting transmitted signal is of constant amplitude, with
increasing amounts of power removed from the carrier and displaced to the
sidebands as the modulating signal increases in amplitude.
Fox Hunt : Also known as ARDF (Amateur Radio Direction
Finding). A contest to locate a hidden transmitter.
Frequency: The number of complete waves that pass a
reference point per second. Expressed in Hertz (Hz)
FSK - Frequency Shift Keying: A digital mode in which the
signal is broken into "chunks". Each chunk is then shifted in
frequency slightly above or below the central carrier. Effectively, frequency
modulation used to carry a digital signal.
Fuse : A device that self destructs when too much
current passes through it - used for circuit protection.
G
Gain : How much more effective an antenna is
as a radiator than a half wave dipole (dBd) or a theoretical point
source (dBi). A more directional antenna is considered to have higher gain.
Gel cell : A small sealed lead-acid rechargeable
battery which uses a gel instead of a liquid electrolyte. Often used as backup
power in applications such as alarm panel installations.
GHz : Gigahertz - one billion Hertz (1 000 000 000 Hz)
General coverage : The ability of a receiver to tune
outside the amateur radio bands, typically over an extended continuous
frequency range, to receive signals from non-amateur services such as shortwave
broadcast or marine weather.
GMT : Greenwich Mean Time - the time at Greenwich UK.
Related to Zulu and UTC.
GOTA : (1) Get On The Air - a station available for
supervised public use at Field Day events,
GOTA : (2) Guides On The Air - a programme sponsored
by YL organisations to introduce Girl Guides to amateur radio (see
also: Jamboree on the Air)
Going QRT: Going off the air.
Grey Line also Gray Line : a band around the
earth that separates night from day.
Ground : A direct connection from electrical equipment
to the Earth - often achieved by driving a conducting spike into the ground,
and connecting equipment to it.
Ground (2): A common zero voltage reference point.
Ground-plane Antenna : a quarter wavelength vertical
antenna with radials extending horizontally from its base.
Groud wave propagation : Propagation via
radio waves that travel along the surface of the earth.
G-TOR (Golay - TOR) : A digital FSK mode that
offers faster transfer rate than PACTOR. Rarely used by ham radio operators.
H
Ham: Radio amateur.
HAAT : Height Above Average Terrain.
Harmonic : Integer multiples of the fundamental frequency
being generated, harmonics are present if a signal is not perfectly sinusoidal
or is undergoing intermodulation distortion. Harmonics located outside the
desired band for transmission are normally removed with low-pass filters to
avoid interference to other radio services.
Half Duplex : The ability for a transceiver to transmit
and receive on two different frequencies, but ony one of these at any given
time.
Half wave dipole : An antenna that is half a
wavelength total, fed at the centre.
HASL : Height Above Sea Level.
Often used for mountaintop stations such as repeaters and portable operations
to describe their elevation. Measured in either feet or metres depending on the
country.
hamfest : An event at which hams can buy sell and swap
equipment. Often held in conjuction with lectures and demonstrations of
equipment.
Handle: Name of the operator.
Harmonic : An integer multiple of a frequency.
Harmonic (of a ham) : Slang term for the child of
a ham.
Harmonics: Children of a ham.
Hellschreiber (Hell) : A digital mode for sending
and receiving text using facsimile (fax) technology.
Henry :(H) The unit for inductance
Hertz : Hz - The unit of measure for frequency.
Named after Heinrich Hertz
HF : High Frequency. Frequencies in the range
3MHz to 30MHz, also known as shortwave.
High
Pass Filter :
A filter designed to pass high frequency signals.
hi hi : The morse equivalent of laughter.
Homebrew : Home built equipment. Self-made wireless
equipment.
Horizontal Polarization : An antenna which
projects a radio signal in which the electric field is parallel to the surface
of the earth OR a radio signal of which the electric field is
propagated parallel to the surface of the Earth.
HT (1) : Handheld Transceiver
or HandiTalkie. Usually refers to transceivers that operate in
the 2m and 70cm amateur bands; these are self-contained
hand-held radios which include an antenna and battery and transmit at low
power.
HT (2) : High Tension Voltage. Voltages over
500V
I
IARU : International Amateur Radio Union. An international society that works for and with
national organisations to promote the interests of hams.
IF : Intermediate Frequency, at which signals
are amplified and processed internally within a receiver.
IFK : Incremental Frequency Keying a
variant of MFSK
Image frequency : A frequency separated from that of
the desired received signal by twice the receiver's intermediate frequency.
Ionosphere : a region in the atmosphere that contains
ionised gasses that refract (bend) radio waves and direct them back to earth.
Inductance : A measure of how well a coil stores energy
in the form of a magnetic field.
Inductor : a coil of wire. Inductors are often used
with capacitors in tuned circuits such
as filters and oscillators. Some inductors are wound around a
core of metallic material. This affects their inductance.
Interface: usually refers to a circuit used to connect the
sound card of a computer to a transceiver to allow digital modes to
be used.
Interference : The interaction between a desired
frequency and an undesired frequency.
Intermodulation : The undesired mixing of two or more
frequencies, producing sometimes undesirable additional frequencies.
Insulator : A substance through which electricity does
not pass easily - known as a dielectric in capacitors
IRLP Internet Radio Linking Project. A
method of cross-world linking of repeaters so that very basic equipment can be
used to communicate with hams in other countries.
Inverter : a device that converts a DC source to and AC
output.
ITU : International telecommunication Union.
The international organisation set up to standardise and regulate radio
communications.
J
JOTA : Jamboree On The Air - an annual event
in which scouts worldwide can communicate with each other and radio amateurs
using ham radio equipment.
J-pole antenna : Vertical antenna composed of
two parallel elements of differing widths. The longer element is connected to
signal and the shorter to ground at an intermediate point; the elements are
connected to each other at the base.
JT65 : A weak signal digital mode developed for use in
the VHF and UHF bands for EME and other
"reflected path" modes. The software for this
mode, WSJT was written by Joe Taylor K1JT.
JT65-HF : An adaptation of JT65, for use on
the HF bands.
K
K : The symbol used in CW ( Morse) and digital
modes for "please respond" or "any station respond".
The KN prosign is used to invite a specific station only to respond.
Key : A simple mechanical device used to
send morse code
Keyer : An electronic circuit intended to interface an
amateur CW transmitter to a paddle switch. While multiple variants exist,
typically the keyer will send dit's when the paddle is held in one position and
dah's in the opposite position. As the timing of the Morse dots and
dashes is automatically controlled, code speed is more consistent than that
sent manually using a straight key.
Kilo: Metric system multiplier x1000. Also Phonetic alphabet
letter K
Kilohertz (KHz) : one thousand Hertz (Hz) or one
thousand cycles per second.
L
Lead acid : A rechargeable battery type most commonly
used in automobiles and marine applications. As some batteries can deliver
large amounts of current instantaneously and contain sulphuric acid, these must
be handled with caution.
Lima Lima: Landline or telephone of the station.
Lid : In amateur radio, used to denote a poor or inept
operator; a term originally from landline telegraphy.
LIon, Li-Ion : Lithium-Ion, a small but powerful
rechargeable battery often factory-installed in laptop computers and handheld
devices. As these cells are highly flammable if overheated, they are normally
distributed only as part of pre-fabricated battery packs which internally
include the requisite temperature sensors and charging circuits.
Loading coil : An inductor placed in series with an
antenna element in order to lower the antenna's resonant frequency. May be used
singly or in conjunction with a capacity hat.
Lobe : a an area in the radiation pattern of
an antenna where the radiation is a maximum.
Long path: The longer great circle path between two
stations.
LPDA : Log Periodic Dipole Array. A
multiband Antenna
LSB : (1) Lower Sideband, used primarily in single
sideband operation below 10 MHz
LSB : (2) Least Significant Bit, in transmitted digital
data
M
Mayday: A most urgent distress call (français: «m'aidez» -
help me) solely for use in life-threatening emergencies. The CW equivalent
is SOS. Lesser incidents are signalled using "pan-pan"
(français: «panne» - mechanical breakdown, typically a ship drifting helplessly
or an aircraft's emergency landing) or "security" (français:
«sécurité» - safety, for warnings such as reports of icebergs in shipping
lanes).
Megahertz: One million Hertz (HZ) - same as one million
cycles per second.
Microphone : A device that converts voice into
electrical signals.
Microwave : signals above 1GHZ in frquency.
Microwave Bands : Division of the range of frequencies
above 1GHz into a series of bands.
Mobile:
A mode of operation in which a station may operate from a moving vehicle (mobile)
or a ship at sea (maritime mobile). In CW, mobile and maritime mobile operators
may identify using /M and /MM respectively. As a class of transceiver,
mobile units fall between hand-held (5W or less) and base stations in both
physical size and transmitted power. These units typically operate from the
vehicle's battery and often transmit 50 watts or more using a vertical antenna
mounted to use the metal vehicle body as a ground plane.
Mode : The way electromagnetic waves are changed so
that transmission of information is possible.
Modulation : The process of adding information to a
carrier signal.
Modulator : A device that adds information to a carrier
signal.
Morse Code The code used by CW operators
instead of voice communications
MP73N : A narrow band SSTV Mode
MUF : Maximum usable frequency. The highest frequency
at which a skywave is reflected back to Earth at the ionosphere under current
propagation conditions. Can vary rapidly depending on time of day and sunspot
activity.
MW : Medium Wave, 300-3000 kHz. This range includes
the 160 metres amateur band, the AM broadcast band and the 2182 kHz
marine radiotelephone band.
N
NB: Narrow band. Also noise blanker.
NBFM : Narrow band FM
Negative : no, incorrect
Negative copy : unsuccessful transmission
Negative Feedback A process in which a portion of the
amplifier output is returned to the input, 180 degrees out of phase with the
input signal.
Negative Offset : Used in repeater systems where the
repeater input frequency is lower than the output frequency.
Net : a scheduled and structured on-air meeting of
amateurs - often run and controlled by clubs. A directed net designates one
station to act as net controller; that station is responsible for inviting
other stations to check in (by sending their call signs) and then sequentially
assigns each station a window of time in which to send traffic to other
stations on the net. Intent is to avoid message collisions which otherwise may
be caused by multiple stations attempting to send simultaneously.
NiCad : Nickel Cadmium, generally refers to a type of
rechargeable battery with 1.2 volts per cell.
NiMH : Nickel Metal Hydride, generally refers to a
newer type of rechargeable battery with the same voltage as NiCad cells but
increased capacity. NiMH cells do not exhibit the memory effects associated
with partial discharge of NiCads, but do still need to be recharged before use
if they have been stored for a month or more.
Noise : Unwanted elecromagnetic energy that can
interfere with signal transmission or reception.
NPN : A type of bipolar transistor that has a layer of
P-type semiconductor material sandwiched between layers of N-type semiconductor
material.
Null : A position in the radiation pattern of
an Antenna where the radiation is zero or approaches zero
NVIS : near-vertical-incidence-skywave,
a propagation mode where signals are reflected back down from
directly overhead. Useful for relatively short-distances, overcoming the
limitations of the usual "skip-zone" distance"
O
Ohm : ( \Omega) The unit for resistance
Ohm's Law : Named after George Ohm :- V = IR. V =
voltage, I = current, R = resistance
OLIVIA : A digital mode using multiple FSK carriers;
intended for operation under QRP or weak-signal conditions.
OM : Abbreviation
meaning Old Man - any male operator, regardless of age or marital status.
Old man: Gentleman radio amateur.
OSCAR : Orbiting Satellite Carrying Amateur
Radio
Oscillator : Also known as a frequency synthesiser - A
device that produces a signal at a particular frequency.
OCF : Off Centre Fed Dipole. A dipole that has
sides of unequal length. These are multiband wire antennas
P
P5 : North
Korea. For DX'ers, the most unattainable
contact or a non-existent station. The rarest callsign prefix as one of two countries
worldwide (the other is 7O Yemen)
to have had no licensed radio amateur service at all since 2002.
Packet radio : An early digital radio mode developed in
Canada
in 1978.
PACTOR : An FSK mode that combines packet and AMTOR
technologies.
Parabolic Antenna : An antenna in the shape of a dish
with a parabolic cross section.
Parallel circuit : usually used to describe a tuned
circuit in which the capacitive and inductive elements are parallel to each
other.
PEP : Peak envelope Power. The average power sent to
the transmission line by the transmitter. Can be calculated by multiplying Peak
Envelope Voltage (PEV) by 0.707
Period : The time in seconds taken for a complete wave
to pass a reference point, period is the reciprocal of frequency.
PEV :Peak Envelope Voltage. The maximum voltage on a
transmission line during transmission.
Phonetic Alphabet Specific, easily identifiable,
non-confusable words are used instead of the letters of the alphabet.
Piezoelectric Effect : the ability of a substance to
produce an electric charge when it is deformed physically.
Pi pad : one of the possible configurations used
in Attenuators
PNP : A semiconductor device composed of an N layer
sandwiched between two P layers.
Polarization : Used to describe the orientation of the
electric field produced by an antenna compared to the surface of the Earth.
Portable: A mode of operation in which a station may be
moved for rapid deployment from a temporary location, but is not able to
operate while mobile. In CW, portable operators may identify using /P. Portable
stations differ from mobile stations in that large antennas or other structures
must be folded or stowed away in order to move the station to a new location.
While well-suited to field day or emergency/disaster operations, portable
stations normally do not have a mobile station's ability to continue
transmission while in motion.
Power : The rate of energy consumption. Calculated by
multiplying voltage by current, P = VI
Propagation : How well a signal is transferred from the
sending station to the receiving station, as a function of the path type
(ground wave, sky wave reflection or direct line-of-sight) and related
atmospheric conditions.
Pulling the big switch: Going off the air.
PSK : Phase Shift Keying - a digital mode.
PTT : Push to talk
Q
QAM : Quadrature Amplitude Modulation. A method that
allows simultaneous frequency and amplitude modulation of a signal.
Q Code Three letter codes used instead of sentences or
phrases.
Q of a circuit The quality factor of a resonant circuit
- the ratio of stored power to dissipated power in
the Reactance and Resistance of the circuit.
QCWA : Quarter Century Wireless Association, a
radioamateur club with local chapters in which membership is offered solely to
operators who were first licensed twenty-five or more years ago.
QRM : Man made noise. Can be used to indicate noise
interfering with an amateur station or an amateur station interfering with
other spectrum users.
QRN : Electromagnetic noise from natural sources
interfering with amateur transmissions.
QRP : Low power operations - usually understood to mean
power at or below 5 watts. From QRP, a code requesting that a station
reduce its transmitted power.
QRPp : Very low power operation - at or below 1 Watt.
QPSK : Quadrature Phase Shift Keying. Also known as
Quadraphase Phase Shift Keying. A method of modulating a carrier in digital
transmissions by changing its phase four times, with each change being
represented by two binary digits.
QSB : Fading (of signals). Used in signal reports eg
"your signal is experiencing rapid QSB tonight"
QRSS : Very low speed operation - typically CW below
one character per minute, intended for machine-assisted reception under extreme
QRP or noisy/weak signal conditions. Bandwidth used is a small fraction of 1
Hz. From QRS, a code requesting "send more slowly".
QSL : Confirmation of receipt of transmission.
QST: Message.
QTH : Home, home location, station location.
Quartz crystal : a crystal of ?silicon dioxide cut
to vibrate at a particular frequency when an electric current is
applied to it. Used in high stability oscillators.
R
Rag chewing: On the air conversation.
Regulator : A device - often built to employ a Zener
Diode as reference - which maintains a constant output voltage over a range of
load currents and input voltages.
Repeater : A transceiver - often comprised of separate
transmitted and receiver linked by controlling hardware. A repeater picks up a
radio signal and re-transmits it, allowing weak stations to be heard from
further away than normally possible.
Rock bound: Crystal
controlled.
Repeater council : A voluntary regional amateur
organisation coordinating repeater frequency pair assignments to minimise
interference. As no individual amateur group owns any given radio frequency, a
council does not exercise legal authority to force individual repeater
operators onto a specific frequency, height, location, power or directional
pattern. Nonetheless, amateurs are obligated by national laws to avoid
interference to other amateur stations and official regulatory agencies will
resolve interference complaints between repeater operators by forcing
uncoordinated repeaters to move off frequencies where their operation
interferes with any coordinated repeater.
Resistance : The measure of how much an object (a
resistor) opposes the flow of electric current.
Resistivity : The measure of how strongly
a material (eg plastic) opposes the flow of electric current.
Resistor : A device that opposes the flow of electric
current.
RF : Radio Frequencies : Frequencies
that can pass through space as electromagnetic radiation.
RFI : Radio Frequency Interference
(also BCI - broadcast interference, TVI - television
interference). Normally resolved by installation of filters at the
transmitter, the affected receiver(s) or both.
Ripple : The residual AC left over after rectification
and filtering when an AC supply has been converted to DC'
RIT : Receive Incremental
Tuning, Receive Independant of Transmit. The ability to shift
the receive frequency of a transceiver away from the transmit frequency by a
small amount.
Rig: Wireless equipment.
RMS : Root Mean Square. Calculated by squaring each of
the values on a signal, calculating the mean of the squares, and then taking
the square root of the mean. approximately 0.707 of the peak value.
ROS Digital : An MFSK digital mode created in 2009.
RSGB : Radio Society of Great Britain - national
amateur radio organisation of UK.
RSQ code Used to describe the readability, strength and
quality of digital modes.
RST code Used to describe the readability, strength and
tone of voice or CW transmissions.
RTTY : Radioteletype.
RSV code used to describe the readability, stength and
video quality of SSTV transmissions
RX : Abbreviation for receive or receiver
S
Sayo Nara: Good bye (Japanese)
Semiconductor : an element that is normally an
insulator but which can, under certain physical conditions, be made to conduct.
Series circuit: Usually used to describe tuned circuits in
which the capacitive and inductive elements are in series with each other.
Shack: Wireless station of the radio amateur.
Short path: The close great-circle path between two
stations.
Signal to Noise Ratio S/N : the ratio of signal power
to noise power. The better the S/N ratio, the better the quality of the signal
and the easier it is to decode.
Signing off: Ending the work with a particular station.
Simplex : Transmit and receive on the same frequency -
most often used when communicating directly (not used when operating via voice
repeaters).
SK : Silent Key, a term used in memory of a deceased
radio operator. The SK prosign in Morse code indicates
the end of a message.
Skip : Skip is a radio phenomenon in which signals are
reflected or refracted by the atmosphere and return to earth in unexpected
places, far away from the normal reception zones. In between transmitter and
receiver there is a zone where no transmissions can be heard
Skip Distance : The shortest distance, for a fixed
frequency, between transmitter and receiver.
Skip
Zone : The distance
between the point of no reception and the closest point of reception.
S meter : A meter on a receiver that displays the
relative strength of an incoming signal.
SNP, SNPF : Shared non-protected pair, shared
non-protected frequency. In repeater coordination, an input/output
frequency pair on which no fixed/permanent repeater stations have been
deployed. These frequencies remain available for temporary use only within a
very limited coverage area by portable public service, emergency, search and
rescue operations or short experiments. Individual temporary repeaters on these
frequencies are not regionally-coordinated, so are not protected from mutual
interference with other temporary repeaters on the same frequency.
SOTA : Summits On The Air. An international
event in which operators gain points from contacts to and from mountain
summits over 500m.
Split
operation : Direct communications where transmit and receive are offset
from each other in frequency - most often used by DXpedition stations
which must accommodate large numbers of incoming calls.
Sporadic E-Skip: Unexpected and unpredictable propagation
using refraction in the E Layer.
SSB : Single Sideband. A transmission mode used mainly
in the HF bands.
SSTV : Slow Scan Television - still picture ham
transmissions.
Standing Wave: The vector sum of two waves - in ham radio,
this most usually refers to the forward and reflected waves in a feedline
Sunspot : A region on the sun where an electromagnetic
"storm" is happening. These have an effect on propagation
Sunspot Cycle : A cycle of approximately 11 years in
which the number of sunspots increases and decreases. The broader sunspot cycle
is 22 years as the polarity of the sunspots reverses every 11 years.
Susceptance : the reciprocal of Reactance,
measured in Siemens; symbol S
SWL : Shortwave listener. While SWL's do not operate
licensed transmitting stations, some are using equipment capable of receiving
both radioamateur and broadcast signals. For both, SWL's may submit reception
reports in order to receive QSL cards. On VHF/UHF and above, one who
can receive (but not transmit) is a scanner operator.
SWR : Standing Wave Ratio. The ratio of the height of a
standing wave on a transmission line to the height of an adjacent node.
T
Telegraphy ; text based modes. Includes morse and
RTTY.
Thermionic Valve : (Also known as an Electron
Tube or a Vacuum Tube). A device that creates or modifies an
electrical signal through the movement of electrons in a low pressure (vacuum)
space.
THROB : An MFSK digital mode based on tone pairs.
TNC : Terminal Node Controller - a
device used in packet radio that disassembles and re-assembles packets of data.
TOR (Teleprinting Over Radio): Used in three
digital modes; AMTOR, PACTOR and G-TOR.
Toroid : A donut-shaped solid usually constructed of
ferrite, used as the former for transformers and inductors'
Ticket: Amateur license.
T pad : one of the possible configurations used
in Attenuators
Transceiver : A radio that has both a transmitter and a
receiver, which either share common circuitry or a common housing or both.
Transient : A short spike or trough on a power line,
usually lasting for a few microseconds.
Transmission Line : Also known as feedline.
Tuned Circuit : A capacitor and an inductor, usually in
parallel. The circuit responds strongly at its resonant frequency and is used
to select or tune in wanted signals.
TVI : Interference to television reception.
TX : Abbreviation for transmit or transmission
U
U : CW abbreviation for "you"
UFB : CW abbreviation for "Ultra Fine
Business" or "excellent"
UHF : Ultra High Frequency. Frequencies in the range
300MHz to 3 000MHz
UHF connector : A threaded co-axial RF connector
(PL-259, SO-239) originally designed in the 1930's for use at frequencies in
the 30-300MHz range. (These frequencies are now considered to be VHF.) Most
commonly used in amateur radio stations to make RG-8 or RG-213 cable
connections to HF transceivers.
UR :
CW abbreviation for "your"
USB : (1) Upper Sideband, used primarily for single
sideband operation above 10MHz
USB : (2) Universal Serial Bus, an interface to desktop
PC peripherals
UTC : Coordinated Universal Time. A corrected - using
atomic clocks- version of GMT
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"
W
WAB : Worked All Britain.
WAC : Worked All Continents.
WARC, WRC : World (Administrative) Radio Conference.
Run by the International Telecommunications Union.
WAN : Worked All Neighbours. Used to refer to a
powerful station in a densely-populated area where strong signals overload
broadcast receivers in the immediate vicinity.
WARC Bands : Agreed to at the 1979 WARC, they consist
of the 30m ( 10.100Mhz - 10.150MHz), 17m (18.086MHz -
18.186MHz) and 12m (24.890MHz - 24.990MHz) amateur bands.
WAS : Worked All States. In the US, contacts
with stations in each of the fifty US states.
WAVE : Worked All VE. Contacts with stations in each of
the Canadian provinces.
Waveguide : A hollow tube, typically square in
cross-section, used to carry microwave signals.
Wavelength : The distance in metres between
corresponding points on a wave.
WAXE : Worked All XE / México.
WIA : Wireless Institute of Australia. The national
organisation for Australian hams.
WKD : CW abbreviation for "worked"
WPM : Words per minute.
WRK : CW abbreviation for "work"
Working QTH: Office or business premises of the radio
amateur.
WSPR : Weak Signal Propagation Reporter.
WSJT : Weak Signal Joe Taylor -
named after Joe Taylor who wrote the software.
WX : Weather. See weather
spotting, APRS for transmission of current meteorological readings
via amateur radio. Many 2 metre handheld transceivers are also
capable of extended tuning to permit reception of forecasts over VHF bands
assigned to other services, such as marine radio.
X
XCVR : Transceiver
XIT : The ability to shift the transmit frequency of a
transceiver while maintaining a constant receive frequency.
XTAL : Crystal
XYL : Wife of an amateur operator. (A lady operator is
referred to as YL - young lady.)
Y
Yagi : A directional antenna consisting of a dipole and
at least two additional elements, a slightly longer reflector and one or more
slightly shorter directors. Invented in 1926 by Hidetsugu Yagi and Shintaro
Uda.
YL : Abbreviation for Young Lady, any female operator
regardless of age or marital status.
Young Lady: Lady radio amateur.
Z
Z code Three letter codes for use in military radio
instead of sentences or phrases. An extension (not a replacement) of the
existing Q Code, these added codes are not in use by any of the civilian
services (amateur radio, aviation, marine) currently using Q code.
Zero Beat : one or both of two signals are adjusted so
that they are identical and in phase.
ZL : New
Zealand.
Zulu : (z) Another term for Coordinated Universal Time
(UTC). Also known as GMT (Greenwich Mean Time) eg. 1400 Zulu
0-9
10 code: A series of abbreviations (originally 10-1 through
10-29) created by APCO, the US
association of public safety communications officers, for use on 1950's-era
police radio. As many localities extended the series with their own
non-standard codes, the same codes may have different meanings in different
agencies (even between police and fire services in the same town). Ten codes
are never used in amateur, marine or aviation radio
as Q-codes already are in long-established international use but they
may be heard in the unlicensed CB radio service and on local public-service
frequencies.
11 metres: The 27MHz CB general radio service, nominally
intended for local communications. As no license or callsign is required to
transmit, quality of operating procedure employed on this band may be
criticised as variable at best. Where existing citizen's band procedure, code
abbreviation and slang terminology are incompatible with amateur radio
operating convention, users will find much needs to be re-learned upon leaving
11 metre CB to become licensed radio amateurs.
2, 6, 10, 20, 40, 80, 160 metres : Amateur radio bands.
30: End of message.
33: Love sealed with friendship and mutual respect between
one YL and another YL. (coined by Clara Reger W2RUF, adopted
officially by YLRL in 1940)
73: Goodbye, best regards.
88: Love and Kisses
92 code : A series of telegraphic
abbreviations devised by Western Union in
1859 (originally as numbers 1 to 92). The later Philips Code added
abbreviations for news wire service. While many of the codes are long
forgotten, 19 and 31 (absolute and permissive) train orders continue in
railroad use, the "30" as used by news editors at the end of a story
remains widely known and "73" / "88" greetings are common
in amateur radio.
