Phonetic alphabet, Q-codes and RST reports

Three international standards to know by heart for the exam and on the air.

Phonetic alphabet (ICAO/NATO) — to spell a callsign unambiguously: A Alpha · B Bravo · C Charlie · D Delta · E Echo · F Foxtrot · G Golf · H Hotel · I India · J Juliett · K Kilo · L Lima · M Mike · N November · O Oscar · P Papa · Q Quebec · R Romeo · S Sierra · T Tango · U Uniform · V Victor · W Whiskey · X X-ray · Y Yankee · Z Zulu.

Q-codes — three-letter abbreviations, usable as a question ("QRZ?") or a statement. The most common:

Code Meaning
QRZ Who is calling me?
QRM Interference (from other stations)
QRN Atmospheric noise / static
QSB Signal fading
QRP / QRO Low / high power
QSO A contact
QSL Acknowledgement of receipt
QSY Change frequency
QTH Position / location
QRT Stop transmitting

RST report — grading a received signal:

In voice you therefore give RS (e.g. "59" = perfectly readable, very strong); in CW you add the T ("599").

Related: Indicatifs, trafic et journal · Bruit de fond, SNR et sensibilité