Glossary Flashcards
(150 cards)
1
Q
73
A
Ham abbreviation for “best regards.” Generally expressed at the end of a contact.
2
Q
Adapters
A
Connectors that convert one type to another.
3
Q
Allocations
A
Frequencies authorized for a particular FCC telecommunications service.
4
Q
Alternating current or voltage (ac)
A
Electrical current or voltage with a direction or polarity, respectively, that reverses at regular intervals.
5
Q
Amateur operator
A
A person named in an amateur operator/primary license station grant on the ULS consolidated license database to be the control operator of an amateur station.
6
Q
Amateur Radio Emergency Services (ARES)
A
An organization of amateurs volunteers that is sponsored by the ARRL and provides emergency communication services to groups such as the American Red Cross and local Emergency Operations Centers (EOC)
7
Q
Amateur service
A
A radio communication service for the purpose of self-training, inter communication 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.
8
Q
Amateur station
A
A station licensed in the amateur service, including necessary equipment, used for amateur communication.
9
Q
Amateur television (ATV)
A
Analog fast-scan television using commercial transmission standards (NTSC in North America)
10
Q
American Radio Relay League (ARRL)
A
The national association for Amateur Radio.
11
Q
Ammeter
A
A test instrument that measures current.
12
Q
Ampere (A)
A
The basic unit of electrical current, also appreciated amps. One ampere is the flow of one coulomb of charge per second.
13
Q
Amplifier
A
A device or piece of equipment used to amplify a signal.
14
Q
Amplify
A
Increasing the strength or amplitude of a signal.
15
Q
Amplitude
A
The strength or magnitude of a signal.
16
Q
Amplitude modulation (AM)
A
The process of adding information to a signal or carrier by varying its amplitude. Transmissions referred to as AM Phone are usually composed of two side bands and a carrier. Shortwave broadcast stations use this type of AM, as do stations in the Standard Broadcast Band (535-1710 kHz). AM in which only one side and is transmitted is called a single-side and (SSB) and is the most popular mode on the high frequency (HF) bands.
17
Q
AMSAT (Radio Amateur Satellite Corporation)
A
Organization that manages many of the amateur satellite programs.
18
Q
Analog (linear) signal
A
A signal (usually electrical) that can have any amplitude (voltage or current) value, and whose amplitude can vary smoothly over time.
19
Q
Antenna
A
A device that radiates or receives radio frequency energy.
20
Q
Antenna switch
A
A switch used to connect one transmitter, receiver or transceiver to several different antennas.
21
Q
Apogee
A
The point in a satellite’s orbit at which it is farthest from the Earth. See perigee.
22
Q
Automatic Packet Reporting System (APRS)
A
A system by which amateurs report their position automatically by radio to central servers from which their locations can be observed.
23
Q
Amateur Radio Direction Finding (ARDF)
A
Competitions in which amateurs combine orienteering with radio direction finding.
24
Q
Anode
A
The more positively charged electrode of a diode or vacuum tube.
25
Antenna analyzer
A portable instrument that combines a low-power signal source, a frequency counter and an SWR meter. AKA SWR analyzer.
26
Array
Antenna with more than one element. In a driven array all elements are driven elements. In a parasitic array some elements are parasitic elements.
27
Attenuate
To reduce the strength of a signal. An attenuator is a device that attenuates a signal.
28
Audio frequency (AF) signal
An ac electrical signal in the range of 20 Hz to 20 kHz (20,000). This is called an audio signal because human hearing responds to sound waves in the same frequency range.
29
Automatic control
A station operation under the control of devices or procedures that ensure compliance with FCC rules.
30
Automatic gain control (AGC)
A circuit that automatically adjusts RF Gain in a receiver to maintain a relatively consistent output volume.
31
Automatic level control (ALC)
A circuit that automatically controls transmitter power to reduce distortion of the output signal that can cause interference to other stations.
32
Automation Repeat Request (ARQ)
The method of requesting a retransmission of data if the data is received with errors. Also known as Automatic Repeat Query.
33
Autopatch
A device that allows users to make telephone calls through a repeater.
34
Auxiliary station
A station that operates in support of another station, such as a repeater, by transmitting control information or relaying audio.
35
Balanced line
Transmission line in which none of the conductors is connected directly to ground.
36
Balun
Contraction of “balanced to unbalanced” and pronounced “BAHL-un.” A device to transfer power between a balanced load and an unbalanced feed line or device, or vice versa.
37
Band-pass filter (BPF)
A filter designed to pass signals within a rage of frequencies called the pass-band, while attenuating signals outside the pass-band.
38
Band plan
Voluntary organization of activity on a amateur band under normal circumstances.
39
Bandwidth
1) Bandwidth is the range of frequencies occupied by a radio signal.
2) FCC part 97 defines bandwidth for regulatory purposes as “The width of a frequency band outside of which the mean power is attenuated at the least 26 dB below the mean power of the transmitted signal within the band” [Part 97.3 (8)]
40
Base
1) A station at a fixed location
| 2) Transistor
41
Battery
A package of one or more cells.
42
Battery pack
A package of several individual cells connected together (usually in series to provide higher voltages) and treated as a single battery.
43
Baud
The rate at which signals are transmitted in a digital mode.
44
Baudot
The code used for radioteletype (RTTY) characters
45
Beacon stations
An amateur station transmitting communications for the purposes of abbreviation of propagation and reception or other related experimental activities.
46
Bit error rate (BER)
The rate at which bit-level errors occur in a stream of digital data.
47
Block diagram
A drawing using boxes to represent sections of a complicated devices or process. The block diagram shows the connections between sections. A block diagram show the internal functions of a complex piece of equipment without the detail of a schematic diagram.
48
BNC
A type of RF connector.
49
Bonding
Connecting equipment or circuits together to keep them at the same voltage.
50
Break-in
Switching between transmit and receive during CW operation so that you can listen to the operating frequency between Morse elements (full break-in) or during short pauses in your transmissions (semi-break-in).
51
Broadband Hamnet
Amateur system that uses reprogrammed commercial network equipment in shared bands to create self-organizing (ad hoc) data networks.
52
Broadcasting
One-way transmissions intended to be received by the general public, either direct or relayed.
53
Bug
A mechanical Morse key that uses a spring to send dots automatically.
54
Bus
An electrical conductor for distributing power or to provide a common connection.
55
Call
1) Abbreviated form of call sign
| 2) Attempt to make contact
56
Call district
The ten administrative areas established by the FCC
57
Call sign
The letters and numbers that identify a specific amateur and the country in which the license was granted.
58
Calling frequency
A frequency on which amateurs establish contact before moving to a different frequency. Usually used by Hans with a common interest or activity.
59
Capacitance
A measure of the ability to store energy in an electric field. Capacitance is measured in farads.
60
Capacitor
An electrical component that stores energy in an electric field. Capacitors are made from a pair of conductive surfaces called electrodes that are separated by an insulator called the dielectric.
61
Carrier
The unmodulated RF signal to which information is added during modulation.
62
Cathode
The more negatively charged electrode of a diode or vacuum tube.
63
Cell (electrochemical cell)
A combination of chemicals and electrodes that converts chemical energy into electrical energy. (See battery).
64
Centi (c)
The metric prefix for 10^-2 or division by 100.
65
Certificate of Successful Completion of Examination (CSCE)
A document that verifies that an individual has passes one or more exam elements. A CSCE is good for 365 days and may be used as evidence of having passed an element at any other amateur license exam session.
66
Channel
1) A range of frequencies used for one radio or communications signal.
2) The structure connecting the source and drain of FET and through which current flows.
67
Channel spacing
The difference in frequency between channels.
68
Characteristic impedance
The radio of RF voltage to current in a transmission line that is matched.
69
Charge
Store energy in a battery by reversing the chemical reaction in its cells.
70
Chassis ground
The common connection for all parts of a circuit that connects to the metal enclosure or chassis (pronounced “CHAA-see”) of the circuit.
71
Check in
Register your station’s presence on a net with the net control station.
72
Checksum
A method of detecting errors in digital data by including a calculated value with the data.
73
Choke Balun
A type of balun made by forming a coaxial feed line into a coil or placing ferrite cores on the feel line, created an RF choke.
74
Circuit
A conductive path through which current can flow
75
Circuit breaker
A protective component that “breaks” or opens a circuit or tripes when an excessive current flow occurs.
76
Citizen’s Band (CB)
An unlicensed radio service operating near 27 MHz intended for use by individuals and business over ranges of a few miles.
77
Closed repeater
A repeater that restricts access to members of a certain group of amateurs.
78
Closed circuit
An electrical circuit with an uninterrupted path for the current to follow. Turning a switch on, for example, closes or completes the circuit, allowing current to flow. Also called a complete circuit.
79
Coaxial cable
Coax. A type of transmission line with a single center conductor inside an outer shield made from brain or solid metal and both sharing a concentric central axis. The outer conductor is covered by a plastic jacket.
80
Color code
A system in which numerical values are assigned to various colors. Colored stripes or dots are painted on the body of resistors and other components to represent their value.
81
Common
Term for the shared reference for all voltages in circuit. Also referred to as circuit common. See ground and bonding.
82
Common-mode
Currents that flow equally on all conductors of a multi conductor cable such as speaker wires or telephone cables, or on the outer surface of shielded cables.
83
Communications emergency
A situation in which communication is required for immediate safety of a human life or protection of property.
84
Component
1) A device having a specific quantity of an electrical property (such as resistance) or that has a specific electrical function.
2) One signal of a group that makes up a composite signal.
85
Composite signal
A signal with information encoded by a group of component signals. For example, an AM signal is a composite signal that consists of three components: The carrier, the upper sidebar (USB) and lower sidebar (LSB).
86
Conductor
A material in which electrons move freely in response to an applied voltage.
87
Connector
A component used to connect and disconnect electrical circuits and equipment.
88
Continuous wave (CW)
Radio communications transmitted by on/off keying of a continuous radio-frequency signal. Another name for international Morse Code.
89
Control code
Information in the form of data or tones used to adjust a station under remote control.
90
Control link
The means by which a control operator can make adjustments to a station operating under remote control.
91
Control operator
The person designated by the licensee of a station to be responsible for the transmissions of an amateur station.
92
Control point
The location at which the control functions of the station are performed.
93
Controlled environment
Any area in which an RF signal may cause radiation exposure to people who are aware of the radiated electric and magnetic fields and who can exercise some control over their exposure to these fields. The FCC generally considers amateur operators and their families to be in a controlled RF exposure environment to determine the maximum permissible exposure (MPE) levels.
94
CORES
Commission Registration System of the FCC
95
Core
In an inductor, the core is the material or space the wire is wound around or passed through.
96
Coulomb (C)
The basic unit of electrical charge. One coulomb is 6.25 x 10^18 electrons. 1 ampere equals the flow of 1 coulomb of electrons per second.
97
Courtesy tone (beep)
A short burst of audio transmitted by a repeater to indicate that the previous station has stopped transmitting. It can also be used to indicate that the time-out-timer has been reset.
98
CQ
“Calling any station,” the general method of requesting a contact with any station.
99
Crossband
Able to receive and transmit on different amateur frequency bands. for example, a repeater might receive a signal on 70cm and retransmit it at 2 meters.
100
CTCSS
Continuous Tone Coded Squelch System. A low frequency tone (also called subaudible tone) required to access many repeaters.
101
Current (electrical)
The movement of electrons in response to an electromotive force, also called electronic current. Conventional currents is the flow of positive charge that moves in the opposite direction of electronic current.
102
Cutoff frequency
The frequency at which a filter’s output power is reduced to one-half the input power.
103
Cycle
One complete repetition of a repeating waveform, such as a sine wave
104
D region
The lowest region of the ionosphere. The D region (or layer) acts mainly to absorb energy from radio waves as they pass through it.
105
Data (digital) mode
Computer-to-computer communication, such as by packet radio or radioteletype (RTTY), in which information is exchanged as data characters or digital information.
106
DC voltage
A voltage with constant polarity. See direct current.
107
Direct detection
A device acting as an unintentional receiver by converting a strong RF signal directly to voltages and currents internally, usually resulting in radio frequency interference to the receiving device.
108
Directional antenna
An antenna with an ability to receive and transmit that is enhanced in a specific (forward) direction and attenuated in one or more directions. See front-to-back ratio and front-to-side ratio.
109
Director
A parasitic element of a Yagi antenna that focuses the radiated signal in the desired direction. See reflector.
110
Discharge
Extract energy from a battery or cell. Self-discharge refers to the internal loss of energy without an external circuit.
111
Dish
A curved directional antenna that uses a reflector to focus radio waves.
112
Distress call
A transmission made in order to attract attention in an emergency. See MAYDAY and SOS.
113
Doping
Adding impurities to semiconductor material to change its conductive properties. N-type material is created if adding the impurity results in more electrons being available to flow as current. P-type material results if fewer electrons are available.
114
Doppler shift
A change in observed frequency of a signal caused by relative motion between the transmitter and receiver. Also called the Doppler effect.
115
Doubling
Two or more operators transmitting at the same time on the same frequency.
116
Downlink
Transmitted signals or the range of frequencies for transmissions from a satellite to Earth. See uplink.
117
Driven element
An antenna element supplied directly with power from the transmitter.
118
Driver
The amplifier stage immediately preceding a power amplifier in a transmitter.
119
Dual-band antenna
An antenna designed for us on two different amateur bands.
120
Dummy antenna or dummy load
A station accessory that dissipates a transmitted signal as heat to allow testing or adjustment of transmitting equipment without radiating a signal on the air.
121
Duplex
1) Transmitting on one frequency and receiving on another, such as for repeater operation.
2) A mode of communications (also know as fully duplex) in which a user transmits on one frequency and receives on another frequency simultaneously. This is in contrast to half duplex in which the user transmits at one time and receives at other times.
122
Duplexer
A device that allows bidirectional communication on closely spaced frequencies or channels. In a repeater, the duplexer also allows the transmitter and receiver to share a single antenna.
123
Duty cycle
The percentage of time that a signal or device, such as a transmitter, is active. Duty factor is the same as duty cycle, but expressed as a fraction instead of percent.
124
DX
Distance, distant stations, foreign countries.
125
DXpedition
An expedition for the purpose of making contacts from a rare or unusual location.
126
E region
The second lowest ionospheric region, the E region (or layer) exists only during the day. Under certain conditions, it may refract radio waves enough to return them to Earth.
127
Earth connection
An electrical connection to the Earth for electrical safety purposes. See also ground.
128
Earth station
An amateur station located on or within 50 km of the Earth's surface, intended for communication with space stations or with other Earth stations by means of one or more other objects in space.
129
Earth-Moon-Earth (EME) or moonbounce
A method of communication with other stations by reflecting radio signals off the Moon's surface.
130
Echolink
A system of linking repeaters and computer-based users by using the Voice-Over-Internet Protocol.
131
Electric field
A region of space in which electrical energy is stored and in which a stationary electrically charged object will feel a force. The electric potential between two points in the electric field is the amount of energy required to move a single electron between those two points.
132
Electrode
The general term for an electrical contact or connection point.
133
Electromagnetic wave
Energy composed of a continuously varying electric field and magnetic field moving through space or a transmission line.
134
Electromotive force (EMF)
The force that causes electrons or other charged objects to move.
135
Electron
A negatively charged atomic particle. Moving electrons make up an electrical current.
136
Element
1) The conducting part of parts of an antenna designed to radiate or receive radio waves.
2) An examination for an FCC license in the amateur service.
3) A dot or dash in the Morse code.
137
Elmer
A ham radio mentor or teacher.
138
Emcomm
An abbreviation for emergency communications
139
Emergency
A situation where there is an immediate threat to the safety of human life or property.
140
Emergency communications
Communications conducted under adverse conditions where normal channels of communications are not available.
141
Emergency traffic
Messages with life and death urgency or requests for medical help and supplies that leave an area shortly after an emergency.
142
Emission
The transmitted signal from an amateur station.
143
Emission privilege
Permission to use a particular emission type (such as Morse code or voice)
144
Emission types
Term for the different modes authorized for use on the Amateur Radio bands. Examples are SW, SSB, RTTY, and FM.
145
Emitter
See transistor.
146
Encoding
Changing the form of a signal into one suitable for storage or transmission. Decoding is the process of returning the signal to its original form.
147
Encryption
Changing the form of a signal into a privately-known format intended to obscure the meaning of the signal. Decryption is the process of reversing the encryption.
148
Energy
The ability to do work; the ability to exert a force to move some object.
149
Envelope
The outline of an RF signal formed by the peaks of the individual RF cycles.
150
Extended-coverage receiver
A receiver that tunes frequencies from around 30 MHz to several hundred MHz or into the GHz range. Also known as a wide-ranger receiver.
