Q Codes Reference Guide

Q-codes are often used in ham radio communications, day to day but you may also encounter them used elsewhere, Some more then others. Some I have honest to God, never heard and others I hear daily. The ones I decided to compile here are somewhat in order of how often I encounter them. Many, if not most, can be used in question form or response form meaning slightly different things at time yet complementary.

Q-CodeStatement / Answer FormQuestion Form
QSLI acknowledge receipt / Got it OKCan you acknowledge receipt?
QRZYou are being called by (Station)Who is calling me?
QTHMy location / Operating LocationWhere are you? / Location?
QSYChange Frequency toShould I change frequency?
QRMThere is man made interferenceIs there any (Man made) interference?
QRNThere is atmospheric noiseIs there any atmospheric noise?
QSBSignal is fading.Is my signal fading?
QSTAttention all stations / AnnouncementNone
QRVI am / Station is ready to receiveAre you ready to receive?
QRPDecrease power / Sending low powerShall I decrease power?
QROIncrease power / Sending high powerShall I increase power?
QRTStop sending / Station is shutting downShould I stop sending?
QRXStand byShould I stand by?
QRLI am busyAre you busy?
QSKBreak in / I can hear between signalsCan you hear me while transmitting? (Between signals)
QRQSpeed up CWShould I speed up my CW?
QRSSlow down CWShould I slow down my CW?
QSPI can relay a message.Can you relay a message?
QRUI have no messages for you.Do you have any messages for me?

The above are the most common Q-Codes you are likely to encounter. You may however encounter some additional ones and if you are curious as to their meaning, your best resource is the Wikipedia Q-Codes Page.

If you find something incorrect and/or have an update, I would really appreciate if you could let me know by contacting me. I like to keep things as up-to-date as possible. Thank you! - Lucas / W6AER