Informal use of the most common Q-codes
QRG - Frequency
QRM - Interference from other stations
QRN - Interference from atmospheric noise or from nearby electrical apparatus
QRO - High-power
QRP - Low-power
QRT - Close(d) down
QRV - Ready
QRX - Stand by
QSB - Fading
QSL - Verification card; confirm contact
QSY - Change frequency
QTC - Message
QTH - Location
QTR - Time
Note also: QTHR means: Address is correct in the current RSGB yearbook
