Why use Q codes?
Q codes are short three-letter codes that make radio communication quicker. They began in radiotelegraphy and are also used in voice contacts. The meaning can be a question or a statement, depending on how it is used.
Common Q codes
QTH asks for or gives the station location. QRM refers to interference from other stations. QRN refers to natural or atmospheric noise. QSY means change frequency. QSL refers to confirmation or acknowledgement. QRT means stop transmitting or close the station.
More useful Q codes
QRZ asks who is calling. QRV means ready. QRX asks for a wait or indicates a wait. QSB refers to fading. QSO means a contact or communication. QSL is also used for a confirmation card or electronic confirmation.
Do not confuse similar codes
QRM is man-made interference from other stations or equipment. QRN is noise from natural or atmospheric sources. QSB is fading. QSY is a frequency change. Learn the difference between these terms.
Common operating abbreviations
CQ is a general call. DE means 'from' in Morse procedure. K invites a reply. KN invites a reply from a specific station. BK is a break in a contact. R means received or understood in common Morse use. Use abbreviations only when they are understood.
Morse prosigns
A prosign is a group of Morse characters sent without the normal letter spacing between them. AR marks the end of a message. SK or VA marks the end of a contact. BT separates parts of a message. These forms should be learned from a reliable Morse reference.
Plain-language rule
Do not use secret codes to hide the meaning of ordinary international amateur communications. Standard procedural signals and technical digital protocols are not the same as deliberate concealment. Follow the applicable national and ITU rules.
Phonetic alphabet reference
The table below gives the standard ITU/NATO phonetic words commonly used to spell call signs.