Basic list of common ‘Q-Codes’ as used in radio communications:
QTH – My location / Where are you?
QRZ – Who’s calling me?
QSY – Change frequency
QRM – Interference from other signals
QRN – Interference from natural noise
QRP – Low power / Decrease?
QRO – High power / Increase?
QSB – Signal fading
QSO – Contact / Conversation
QRV – I am ready / Are you ready?
QRT – Stop transmitting / Going off air
QSL – Confirm / Acknowledge