Amateur communications: Non-commercial radio communication by or among amateur stations solely with a personal aim and without personal or business interest.
Amateur operator/primary station license: An instrument of authorization issued by the Federal Communications Commission comprised of a station license, and also incorporating an operator license indicating the class of privileges.
Amateur operator: A person holding a valid license to operate an amateur station issued by the FCC. Amateur operators are frequently referred to as ham operators.
Amateur radio services: The amateur service, the amateur-satellite service, and the radio amateur civil emergency service.
AMSAT: Radio Amateur Satellite Corporation, a non-profit scientific organization.
Ares: The emergency division of the American Radio Relay League.
ARRL: American Radio Relay League, national organization of U.S. amateur radio operators.
Audio frequency: The range of frequency that can be heard by the human ear, generally 20 hertz to 20 kilohertz.
Authorized bandwidth: The allowed frequency band, specified in kilohertz, and centered on the carrier frequency.
Beam or Yagi antenna: An antenna array that receives or transmits RF energy in a particular direction. Usually rotatable.
Business communications: Any transmission or communication the purpose of which is to facilitate the regular business or commercial affairs of any party. Business communications are prohibited in the amateur service.
Call Book: A published list of all licensed operators.
Call sign assignment: The FCC systematically assigns each amateur station their primary call sign.
Carrier frequency: The frequency of an unmodulated electromagnetic wave, usually specified in kilohertz or megahertz.
Certificate of Successful Completion of Examination: A certificate of successful completion allowing examination credit for 365 days. Both written and code credit can be authorized.
Control operator: An amateur operator designated by the licensee of an amateur station to be responsible for the station transmissions.
Coordinated Universal Time (UTC): Sometimes referred to as Greenwich Mean Time, UTC, or Zulu time. The time at the zero-degree Meridian which passes through Greenwich, England. A universal time among all amateur operators.
CW: Continuous wave, another term for the International Morse code.
Dipole antenna: The most common wire antenna. Length is equal to one-half of the wavelength.
FCC Form 610: The amateur service application form for an amateur operator/primary license. It is used to apply for a new license or to renew or modify an existing license.
Federal Communications Commission: A board of five Commissioners, appointed by the President, having the power to regulate wire and radio telecommunications in the United States.
Field Day: Annual activity sponsored by the ARRL to demonstrate emergency preparedness of amateur operators.
Ground: A connection, accidental or intentional, between a device or circuit and the earth or some common body serving as the earth.
Ground wave: A radio wave that is propagated near or at the earth's surface.
Harmful Interference: Interference which seriously degrades, obstructs, or repeatedly interrupts the operation of a radio communications service.
Harmonic: A radio wave that is a multiple of the fundamental frequency. The second harmonic is twice the fundamental frequency, the third harmonic, three times, etc.
High frequency (HF): The band of frequencies that lies between 3 and 30 megahertz. It is from these frequencies that radio waves are returned to the earth from the ionosphere.
Ionosphere: Outer limits of atmosphere from which HF amateur communications siganls are returned to earth.
Lid: Amateur slang term for a poor operator.
Linear Amplifier: A device that accurately reproduces a radio wave in magnified form.
Long wire: A horizontal wire antenna that is one wavelenth or longer.
MARS: Military Affiliate Radio System. An organization that coordinates the activities of amateur communications with military radio communications.
Morse code: The International Morse Code, A1A emmission. Interrupted continuous wave communications conducted using a dot-dash code for letters, numbers, and operating procedure signs.
OSCAR: Stands for "Orbiting Satellite Carrying Amateur Radio", the name given to a series of satellites designed and built by amateurs of several nations.
Propagation: The travel of electromagnetic waves or sound waves through a medium.
QSL Bureau: An office that bulk processes QSL (radio confirmation) cards for (or from) foreign amateur operators as a postage saving mechanism.
RACES (radio amateur civil emergency service): A radio service using amateur stationsfor civil defense communications during periods of local, regional, or national civil emergencies.
Single-Sideband (SSB): A method of radio transmission in which the RF carrier and one of the sidebands is suppressed and all of the information is carried in the one remaining sideband.
Sky wave: A radio wave that is refracted back to earth in much the same way that a stone thrown across water skips out. Sometimes called an ionospheric wave.
Sunspot cycle: An 11-year cycle of solar disturbances which greatly affects radio wave propagation.
Transceiver: A combination radio transmitter and receiver.
Ultra high frequency (UHF): Ultra high frequency radio waves that are in the range of 300 to 3000 MHz.
Very high frequency (VHF): Very high frequency radio waves that are in the range of 30 to 300 MHz.
Volunteer Examiner: An amateur operator of at least a General class level who administers or prepares amateur operator license examinations. A VE must be at least 18 years old and not be related to the applicant.
Volunteer Examiner Coordinator: A member of an organization which has entered into an agreement with the FCC to coordinate the efforts of volunteer examiners in preparing and administering examinations for amateur operator licenses