|
|
- am (amplitude modulation)
- a radio transmission
mode in which the strength of the speech signal controls
the strength of the transmitter signal. This normally
resuilts in two sidebands containing the modulation
energy.
- AMSAT - Radio Amateur Satellite
Corporation - an amateur radio organization promoting
and developing amateur radio satellite service. Over two
dozen satellites are now in operation, many as a result
of AMSAT effort.
- APRS (Amateur Packet Reporting
System) - a system which supports plotting of station
positions on screen maps
- ASL (above sea level) - a
method of measuring antenna height
- access code - one or more numbers and/or
symbols that are keyed in with a telephone key pad to
activate a repeater function e.g autopatch, link etc
- antenna separation - the physical spacing between
transmit and receive antennas, when separate antennas are
used
- autopatch - a device that interfaces a
repeater to the telephone system to permit repeater users
to make telephone calls. Often called a "patch"
- band (amateur radio frequency band)
- the range of contiguous frequencies over which amateurs
may communicate
- band-opening - a condition that results in
greater-than-normal communication range on the VHF and
UHF bands
- band-plan - a voluntary system of frequency
allocations in each amateur radio band
- break - the word used to interrupt a
conversation on a repeater , often to indicate that there
is an emergency
- CAS (carrier activated switch)
- see COR
- COR (carrier-operated relay) -
a device that causes the repeater to transmit in response
to a received signal
- CTCSS (Continuous Tone-Coded Squelch
System) - This is a sub-audible tone transmitted by
your radio in addition to your voice signal. When it is
equipped with a CTCSS decoder, a repeater will not
function unless it hears the CTCSS tone and the
"carrier" signal from your transmitter.
Different CTCSS tones are in use for different repeaters
or areas. These may be applied to input or output
frequencies, or both. CTCSS tones are used to minimize
the effects of co-channel interference due to
band-openings causing reception of distant signals
- carrier - your unmodulated (no speech)
transmitter signal
- cavity resonator - a sharply tuned circuit using
the physical dimensional resonance of one or more tuned
cavities
- channel - the pair of frequencies
(input and output) used by a repeater
- channel spacing - the frequency spacing between
adjacent frequency allocations - may be 50, 30, 25, 15 or
12.5kHz, depending upon the convention in use in the area
of the repeater
- clear - indicates the end of a contact
- closed repeater - a repeater whose access is
limited to a select group (see also open repeater)
- co-channel interference - the interference resulting when
a repeater receives signals from a distant repeater on
the same frequency pair
- controller - the control system within a
repeater which may include turning the repeater on-off,
timing transmissions, sending the identification signal,
controlling the autopatch and CTCSS encoder/decoder
- control operator - the amateur radio operator who
is designated to control the repeater
- courtesy tone - an audible indication that the
repeater user may go ahead and transmit
- coverage - the geographic area within which
the repeater provides communications
- cross-band - the process of transmitting on
one band and receiving on another
- DTMF - see tone pad
- desense (desensitization) - the reduction of receiver
sensitivity due to overload from a nearby transmitter
- digimodes (digital modes) - the various digital transmission
modes, including packet, RTTY (radio teletype), etc
- digipeater (digital
repeater) - a
packet radio repeater
- dropping out - the situation, while using a
repeater, when your signal does not have enough strength
to keep the repeater triggered.
- duplex - a mode of communication in which
you transmit on one frequency and receive on another
frequency (see also half and full duplex)
- duplexer - highly selective filter which
allows a repeater's transmitter and receiver to share one
antenna
- EIRP (effective radiated
power referred to isotrope) - ERP plus 2.14 dB to correct for
reference to isotrope
- ERP (effective radiated
power) -
radiated power, allowing for transmitter output power,
line losses and antenna gain
- fm - see frequency modulation
- frequency coordinator - an individual or group
responsible for assigning channels to new repeaters with
minimal interference to existing repeaters
- frequency modulation - a method of modulation, where the
strength of the signal is constant, but the frequency
varies with the strength of the voice, and the rate of
change varies with the frequency of the voice
- full duplex - a mode of communication in which
you transmit on one frequency while you simultaneously
receive on another frequency
- full quieting - a received signal that contains
no noise
- gateway - a link or
bridge between one communication network and another. Can
be repeater to satellite
- HAAT (height above average
terrain) - a
method of measuring antenna height
- half duplex - a mode of communication in which
you transmit at one time on one frequency and receive at
another time on another frequency
- hand-held - a portable transceiver small
enough to fit in the hand, clipped to your belt, or in
your shirt pocket
- handle - slang for your name (not
recommended)
- helical resonator - a compact resonant filter
circuit to block multiple interfering signals
- horizontal polarization
- the antenna elements are horizontal (used at vhf/uhf
for weak signal CW/SSB operation)
- Hz (Hertz) - a unit of frequency measurement
equal to one cycle per second
- ID (identification) - the means by which a station
identifies its call sign by Morse code or speech
- input (frequency) - the frequency of the repeater's
receiver
- intermod (intermodulation
distortion or IMD)
- interference that results when strong signals from
nearby transmitter(s) mix with the desired signal in a
radio receiver
- isolation - the difference in level
(measured in dB) between a transmitted and received
signal due to filtering
- isotrope - a theoretical antenna with zero
dimensions and a spherical radiation pattern. Gain is
-2.14 dB from dipole
- jamming - the action of deliberate illegal
interference with a repeater operation
- kHz (kilohertz) - a unit of frequency measurement
equal to 1,000 cycles per second (Hertz)
- kerchunk - to key up a repeater without
identifying
- key pad - see tone pad
- key up - to turn on the repeater by
transmitting on its input frequency
- linking - the process of connecting
repeaters in a permanent network, or one controlled by
access codes
- MHz (megahertz) - a unit of frequency measurement
equal to 1,000,000 cycles per second (Hertz)
- machine - a slang expression meaning a
repeater system
- magnetic mount (mag-mount) - an antenna with a magnetic base
that permits quick installation and removal from a
metallic surface, including an automobile body
- microwave - the region of the radio spectrum
above 1 gigahertz (GHz)
- modem
(modulator-demodulator) - an interface device for use between
computers. See TNC
- negative offset - the repeater input frequency is
lower than the output frequency
- NiCd (or NicCad) - a nickel cadmium battery that
may be recharged many times; often used in handheld
transceivers
- NiMH - new technology nickel metal
hydride battery that has advantages over NiCd, but is
more expensive
- odd split - unconventional frequency
separation between input and output frequencies.
- offset - see separation
- open repeater - a repeater whose access is not
limited
- OSCAR (Orbiting Satellite
Carrying Amateur Radio) - Acronym describing amateur satellites. A
number applies to a specific satellite e.g. OSCAR-16 or
AO-16.
- out - indicates the end of a contact
- output frequency - the frequency of the repeater's
transmitter (and your receiver)
- over - the word used to indicate the
end of a voice transmission
- positive offset - the repeater input frequency is
higher than the output frequency
- ptt (push to talk) - the use of the microphone button
or control line to key the transmitter on
- packet - the most popular form of digital
mode communications, in which computers communicate via
radio to exchange data "packets"
- pacsat (PACket SATellite) - amateur radio satellite used to
store and forward digital (packet radio) messages.
- PL - Private Line (trademark of
Motoroal Inc) see CTCSS
- Q signals or codes - abbreviations developed for use
on Morse code transmissions. Not recommended for phone.
- radio direction finding
(RDF) - the art
and science of locating a transmitter
- raster - the vertical spacing of
television scanning lines. Used also as slang for channel
spacing
- repeater - an automatic relay station,
generally in a high location, which is used to increase
the range of mobile and handheld FM transmitter/receivers
- repeater directory - a repeater list for a particular
area (RAC publishes one for Canada and neighbouring
states)
- reverse patch - when a call is received on its
incoming telephone line this special autopatch rings over
the air and may be answered by tone access
- rubber duck(y) - slang term for the flexible
rubber-covered antenna supplied with handheld radios
- ssb (single-sideband) - a type of AM transmission which
occupies half the spectrum of a standard AM signal
- sked (schedule) - a prearranged (scheduled)
contact between two stations
- separation (split) - the difference, in kHz, between
the repeater's transmit and receive frequencies.
Conventional separations by amateur band are: 29 MHz -
100 kHz; 50 MHz - 1 MHz; 144 MHz - 600 kHz; 220 MHz - 1.6
MHz; 440 MHz - 5 MHz; 902 MHz - 13 MHz; 1270 MHz - 12
MHz.
- simplex - a mode of communication in which
you take turns to transmit and receive on the same
frequency. A frequency set aside for non-repeater use.
- squelch - a circuit within a radio that
keeps the speaker silenced (squelched) until the signal
level exceeds a certain point, set by the squelch
control. Normally you set the squelch to just block out
noise and allow signals to pass.
- sub-audible tone - see CTCSS
- TNC (Terminal Node
Controller) - the
interface circuitry that goes between the computer and
radio for digimode (normally packet) communications
- tail - the brief signal transmitted by
a repeater transmitter after someone stops talking.
- time-out - to cause the repeater, or a
repeater function, to turn off because you have
transmiited too long
- timer - a device which measures the
length of each transmission and causes the repeater, or a
repeater function, to turn off, after a transmission has
exceeded the preset time.
- tone pad - an array of 12 or 16 numbered
keys that generate the standard telephone dual-tone
multi-frequency (DTMF) dialing signals
- touch tone - trade mark of AT&T. See DTMF
- triggering - to activate a repeater by
transmitting on its input frequency (see also key up)
- translator (linear
translator) - a
device used to directly convert and retransmit a block of
received frequencies
- transponder - the term used for a linear
translator in a satellite. Inverting transponder
transmits received upper sideband as lower sideband.
Non-inverting transponder transmits received upper
sideband as upper sideband
- vhf (very high frequency) - the region of the radio spectrum
between 30 and 300 megahertz (MHz)
- vertical polarization - the antenna elements are
vertical (used at vhf/uhf for FM and repeater operation)
- uhf (ultra high frequency) - the region of the radio spectrum
between 300 and 1000 MHz or 1 GHz
|
