Technicals terms  A ... D

Amateur bands

Frequency range, assigned for use by Amateur Radio

Amplitude modulation

(AM), operating mode for voice comm. The amplitude of the carries varies with the modulation input.

APRS

Automatic Position Reporting System, digital APRS operating mode. GPS position data is transmitted in packet radio mode.

ATV

Amateur Television

Contest

Contest on HF, VHF, direction finding

CW

(Continuous Wave), Morse Code, telegraphy

Digipeater

Digital Repeater, for digital operating mode Packet Radio, serves to forward packet messages and is part of the worldwide Packet Radio Network

DXpedition

"Expedition" of HAMs to isles and foreign countries | to permit communication of other HAMs with these locations