Q CODES

Three letters that work as a question or as an answer, and the single piece of punctuation that decides which.

Where they came from

The Q code began as a British regulation. In 1909 a list of three-letter codes, every one of them starting with Q, was issued for traffic between British ships and coast stations. It was short — a few dozen entries — and it covered the things an operator needed to say a hundred times a watch and did not want to spell out by hand.

The idea spread fast because it solved two problems at once. It cut transmission time, which mattered when every word was keyed by hand through interference, and it crossed languages: a Norwegian operator and an Italian one with no common tongue could still agree completely about QRM. International conventions took the system up, expanded it, and it has been maintained ever since by the ITU, with a separate aeronautical portion administered through ICAO.

The modern allocation carves up the alphabet. QAA to QNZ belongs to aviation. QOA to QQZ is maritime. QRA to QUZ is available to all services, and that is the block amateur radio lives in — which is why practically every code you will hear on the air begins QR or QS. A handful of codes in common use were never official at all. They were invented on the air, spread by imitation, and stuck.

The question mark is the whole mechanic

This is the part newcomers miss, and it is the reason the system works at all. Every Q code carries two meanings. The difference between them is one trailing question mark — ••▬▬•• — and nothing else.

Sent with the question mark, QRL asks whether the frequency is in use. Sent without it, QRL states that the frequency is in use and asks you to go elsewhere. QRS with a question mark offers to slow down; QRS without one tells the other operator to. One code, two directions, no ambiguity and no wasted characters. Many of them take a parameter as well: QRS 10 asks for ten words a minute, QSY 7030 names the frequency to move to, QTC 3 announces three messages waiting.

The question mark is not decorative politeness. Sending QRT without one on somebody else's frequency reads as an instruction to stop transmitting, which is almost certainly not what you meant.

The ones you will actually hear

Question meaning first, answer meaning second.

QRL

Are you busy? / I am busy, please do not interfere. On the amateur bands the question form is the standard courtesy before transmitting on a frequency that sounds empty. Ask twice: a weak station you cannot hear may be working someone you cannot hear either.

QRM

Are you being interfered with? / I am being interfered with. Strictly, interference from other transmitters. Man-made noise, and usually another operator.

QRN

Are you troubled by static? / I am troubled by static. Natural noise: lightning a thousand miles away, atmospherics, the hiss of a summer evening on the lower bands.

QRO

Shall I increase power? / Increase power. As an adjective it means running a big transmitter.

QRP

Shall I decrease power? / Decrease power.

QRQ

Shall I send faster? / Send faster. Usually with a figure attached in words per minute.

QRS

Shall I send more slowly? / Send more slowly. The most useful three letters a beginner can own, and nobody who receives it will think less of you.

QRT

Shall I stop sending? / Stop sending. Operators use the answer form about themselves: I am going off the air.

QRU

Have you anything for me? / I have nothing for you.

QRV

Are you ready? / I am ready.

QRX

When will you call me again? / I will call you again at a stated time. In daily use it has shrunk to a plain stand by.

QRZ

Who is calling me? / You are being called by the station named.

QSB

Are my signals fading? / Your signals are fading. The slow swell and collapse of a skywave signal as the path shifts.

QSL

Can you acknowledge receipt? / I acknowledge receipt.

QSO

Can you communicate with the named station direct? / I can communicate with that station direct.

QSY

Shall I change to another frequency? / Change to transmission on another frequency. Almost always followed by the frequency in kilohertz.

QTC

How many messages have you to send? / I have a stated number of messages for you. Formal traffic handling, and still used by message-relay networks.

QTH

What is your position? / My position is as stated. Officially latitude and longitude. On the amateur bands, a town and a country.

Where usage has drifted

A code that stays in daily use for a century does not stay put. Several of the entries above mean something on the air that the official list would not recognise.

QSL officially asks for, and gives, acknowledgement of receipt. It has since become a noun. A QSL is a printed card confirming a contact, sent direct or through a national bureau, and increasingly an electronic record instead of a card at all. Asking someone for a QSL is asking for paperwork, not for an acknowledgement on the air. The word has also slid sideways into plain agreement, so that QSL alone now often just means understood, agreed, yes.

QRP has outgrown its definition entirely. As a Q code it asks another station to reduce power. As a word on the bands it names an entire practice: working the world with five watts or less on CW, with its own contests, awards, clubs and a long tradition of homebuilt equipment. Calling CQ QRP does not ask anyone to turn anything down. It announces that you are running a small signal and would be grateful for patience. The reverse, QRO, is used the same way for the other end of the scale.

QSO officially concerns whether you can reach some third station directly. In use it simply means a contact, and it works as a noun and a verb alike: a first QSO, a long QSO on twenty metres, to QSO somebody. The original sense has effectively disappeared.

QRM and QRN get used loosely and often interchangeably, but the distinction is real and worth keeping, because the two have different cures. QRM is another transmitter sitting on top of you, and the fix is to move. QRN is nature, and the fix is to wait, change band, or accept it. Operators also say QRM for anything irritating, including a neighbour's switching power supply, which is strictly neither one nor the other.

QRZ has drifted from a specific question — who is calling me — into a general solicitation. Sent on its own at the end of a contact it means whoever else is out there, go ahead, which is closer to a short CQ than to anything in the printed definition. QTH is now a plain noun for home, and QRT is used for retiring from the hobby altogether. None of this is wrong exactly. It is what happens to any vocabulary that gets worked hard for a hundred years.

Sending them

Q codes are keyed as three ordinary letters with normal spacing between them. They are abbreviations, not prosigns, and the difference is set out in full on the prosigns page: a prosign runs together into one character, a Q code does not. Nobody sends QSL solid, and an operator who did would be misheard.

They survive on voice too, which is faintly absurd given that the entire point was to save keying time, but they persist because they are precise and universally understood, and because saying QSY is quicker than explaining what you mean by it. If you want to hear one at speed rather than read it, feed it to the translator and listen a few times. QSB and QRM have rhythms you will start picking out of the noise before you can consciously decode them, which is exactly how experienced operators read them in the first place.