Q-codes

Three letters, a whole sentence

Q-codes are three-letter signals that all start with Q. They were created for telegraph operators so that common messages could be sent in a few characters, in any language. Each code has two forms: a statement, and the same code with a question mark, which turns it into a question.

The common ones

These are the Q-codes an operator meets every week. The official list is much longer, and only a fraction of it is used in ham radio.

Code	As a statement	As a question
QRL	This frequency is busy	Is this frequency in use?
QRM	I am being interfered with by other stations	Are you being interfered with?
QRN	I am troubled by static (natural noise)	Are you troubled by static?
QRO	Increase power	Shall I increase power?
QRP	Reduce power	Shall I reduce power?
QRQ	Send faster	Shall I send faster?
QRS	Send slower	Shall I send slower?
QRT	I am stopping transmission (shutting down)	Shall I stop sending?
QRU	I have nothing for you	Have you anything for me?
QRV	I am ready	Are you ready?
QRX	I will call you again later; please stand by	When will you call again?
QRZ	You are being called by ...	Who is calling me?
QSB	Your signals are fading	Are my signals fading?
QSK	I can hear you between my signals; break in	Can you hear me between your signals?
QSL	I acknowledge receipt (I got that)	Can you acknowledge receipt?
QSO	I can communicate with ... (a contact)	Can you communicate with ... ?
QSP	I will relay the message	Will you relay a message?
QSY	Change frequency ("I am changing to ...")	Shall I change frequency?
QTC	I have messages (traffic) for you	How many messages have you?
QTH	My location is ...	What is your location?

A few memory hooks: QRM is Man-made interference and QRN is Natural noise; QRS is Slow and QRQ is the opposite; QRP is low power and QRO is high.

How they are used in practice

• Ask before you transmit. "QRL?" on CW, or "Is the frequency in use?" on voice, is how you check a frequency before calling CQ. See On-air etiquette.
• One code, both directions. If someone answers your "QRL?" with "QRL", the frequency is busy. No reply means it is probably clear, but listen and ask again.
• Stretched meanings. Hams use some as nouns and verbs: a QSO is a contact, QRP is low-power operating, "QSY" means moving to another frequency, a QSL card confirms a contact. "QRM" and "QRN" are shorthand for human and natural interference.
• Don't double up. The code already carries the meaning: "QRP" alone says low power, and "QRZ?" alone asks who is calling.
• On voice, plain language is clearer. Q-codes shine on CW, where short is fast. On a repeater, just say what you mean.

Related

• Ham abbreviations and numbers73, 88, CQ, DX, QSO and other jargon, decoded.
• On-air etiquetteListening first, calling CQ, taking turns, and being a good neighbour on the band.
• CW procedure and prosignsCalling, QSOs and signing off in Morse.
• The Morse alphabet and timingDits, dahs and spacing.
• The phonetic alphabetWhy we say "Whiskey" for W, and how to spell a call so it gets through.
• Logging and QSL confirmationsKeeping a log, paper cards, Logbook of the World and eQSL.