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ITU, RF & Technical Definitions
A measure of impedance matching between the transmission line and the antenna. An SWR of 1.0:1 is a perfect match.
The transmission of International Morse Code by keying an unmodulated RF carrier wave.
Operating with 5 Watts RF output or less on CW, and 10 Watts PEP or less on SSB.
An efficient form of amplitude modulation where the carrier and one of the sidebands are filtered out.
Amateur radio communication over long distances, typically between different continents or rare countries.
An impedance or isolation transformer connecting a balanced antenna (like a dipole) to unbalanced coax.
A multi-element directional antenna using a driven element, a reflector, and one or more directors for high forward gain.
The fundamental resonant antenna measuring approximately 468/f(MHz) in feet, fed at the center.
A worldwide coordinate locator system encoding latitude and longitude into 4 or 6 alphanumeric characters.
The international astronomical time standard used for all amateur radio logs to avoid time zone ambiguity.
The reduction in signal strength that occurs as radio frequency power passes through coax or filters.
The statutory regulatory authority responsible for administering Amateur Radio licensing exams and callsigns.
United Nations specialized agency that coordinates the global shared use of the radio spectrum.