Morse Code Prosigns and Q-Codes: Meanings and How to Use Them
A prosign is a shortcut signal in Morse code — two or three letters sent as one continuous character to give an instruction, like “end of message” or “stand by.” The ones you’ll hear most: CQ (calling any station), AR (end of message), SK (end of contact), BT (break / separator), and 73 (best regards — technically a number code, not a prosign). The tables below list every prosign and Q-code with its pattern, sound, and meaning.
What Is a Prosign?
A prosign (short for “procedural signal”) is not a letter and not a word. It’s an instruction built from letters. AR doesn’t spell anything — it means “end of message.” SK doesn’t spell anything — it means “end of contact.” Prosigns are the traffic signals of Morse code: they tell the other operator where a message starts and ends, when to wait, and when it’s their turn. If you’re still learning the letters themselves, start with the Morse code alphabet.
How a prosign is sent
When you send AR, you key di-dah-di-dah-dit with no pause between the A and the R. If you pause, the listener hears two separate letters, A and R — and the meaning is gone. The same rule applies to every prosign: no gaps inside the signal.
Between normal letters, there is a 3-unit gap. Inside a prosign, there is no letter gap at all — the elements run together with the same 1-unit spacing used inside a single character. That missing gap is how the listener knows it’s one prosign, not two letters.
How prosigns are written and typed
In print, prosigns are written with a bar over the letters, or in angle brackets: <AR>. On a plain keyboard, <AR> is the standard way to write one.
Decoders often show a prosign as the nearest punctuation character: BT appears as =, AR as +, KN as (, AS as &. So if your decoder prints “73 =”, it means “best regards, break.” Keyer and logging software usually maps punctuation keys to prosigns — check your program’s mapping, because it varies.
Prosigns vs Q-Codes vs Abbreviations
Three kinds of shorthand, three different jobs. Mixing them up is the most common beginner confusion.
| Type | What it is | Example | Job |
|---|---|---|---|
| Prosign | Letters sent as one character | <AR> | Gives an instruction (end of message) |
| Q-code | Three letters starting with Q | QTH | Asks a question or makes a statement (location) |
| Abbreviation | Shortened word or phrase | 73, OM, DE | Saves keying (best regards, old man, this is) |
Trap cases
Some codes sit on the boundary, and sources disagree about them. Here is the honest labeling:
- CQ — a general call (“calling any station”), sent as two normal letters. Often listed with prosigns, but it is not a prosign.
- CL — “closing station.” An abbreviation, often grouped with prosigns. Not a strict prosign.
- BK — “break” / “back to you.” Most operators send it run together as one signal; you’ll also hear it as two letters. It works as an abbreviation either way.
- K — a single letter (dah-di-dah) used as an invitation to transmit. A prosign by function, a letter by form.
- R — a single letter (di-dah-dit) meaning “received.” Same: prosign by function.
- SK — the prosign
<SK>(end of contact) is one run-together signal. Don’t confuse it with “silent key,” a separate term for a deceased operator, also written SK in text. - 73 — not a prosign at all. It’s a number code from the old 92 Code. Included here because everyone asks about it.
The Complete Prosigns Table
| Prosign | Morse pattern | Sound | Meaning | When to use it | Also written as / status |
|---|---|---|---|---|---|
<AA> | .-.- | di-dah-di-dah | New line | In formal message traffic | Also RT |
<AR> | .-.-. | di-dah-di-dah-dit | End of message | Before callsigns at the end of a transmission | Also RN; decoder shows + |
<AS> | .-... | di-dah-di-di-dit | Wait / stand by | Ask the other station to wait | Decoder shows & |
<BK> | -...-.- | dah-di-di-di-dah-di-dah | Break / back to you | Break in, or hand over without full ID | Often sent as two letters |
<BT> | -...- | dah-di-di-di-dah | Break / separator | Separates parts of a message (like a paragraph break) | Decoder shows = |
<CL> | -.-..-.. | dah-di-dah-dit-di-dah-di-dit | Closing station | Your last transmission before going off air | Abbreviation, grouped with prosigns |
| CQ | -.-. --.- | dah-di-dah-dit, dah-dah-di-dah | Calling any station | Start a contact; invite anyone to answer | General call, not a prosign; normal letter spacing |
<CT> | -.-.- | dah-di-dah-di-dah | Start of transmission / start copying | Attention: a message follows | Also KA |
<DDD> | -..-..-.. | dah-di-di-dah-di-di-dah-di-dit | Distress relay | Forwarding an SOS you received | Rare |
<HH> | ........ | 8 dits | Error / correction | You made a mistake; correct text follows | 8 dits, no letter gap |
<K> | -.- | dah-di-dah | Go ahead / over | Invite any station to transmit | Single letter |
<KN> | -.--. | dah-di-dah-dah-dit | Go ahead, named station only | Invite one specific station to answer | Decoder shows ( |
<R> | .-. | di-dah-dit | Received | Confirm you copied the transmission | Single letter |
<SK> | ...-.- | di-di-di-dah-di-dah | End of contact | The last transmission of a contact | Also VA |
<SN> | ...-. | di-di-di-dah-dit | Understood / verified | Message received and checks OK | Also VE |
<SOS> | ...---... | di-di-di-dah-dah-dah-di-di-dit | Distress | Real imminent danger only | Prosign, not an acronym |
| CQD | -.-. --.- -.. | dah-di-dah-dit, dah-dah-di-dah, dah-di-dit | All stations, distress | Distress call that came before SOS | General call, historical |
How to read the table
Patterns use . for dit and - for dah. “Sound” is how the pattern reads to the ear. “Also written as” shows the equivalent code (same pattern, different letters) and what decoders display. The status notes matter: CQ, CL, and CQD are general calls or abbreviations that are often grouped with prosigns — they are not strict prosigns.
The Prosigns You’ll Hear Most
The table above gives the meanings. This section gives the usage notes — what each signal does in a real contact, and the confusion each one causes.
CQ — calling any station
CQ is how a contact starts: “CQ CQ CQ DE [your callsign] K” — calling anyone, this is me, go ahead. It is sent as two normal letters, not run together. If you answer a CQ, you send the caller’s callsign, then DE, then yours.
AR vs SK — end of message vs end of contact
AR ends a message. SK ends the whole contact. A typical contact uses AR several times (at the end of each transmission) and SK once (at the very end). The classic mix-up is sending SK in the middle of a contact, which tells the other station you’re done when you’re not.
BT — break / separator
BT separates parts of a message — like a paragraph break. The listening trap: BT (dah-di-di-di-dah) can sound like two dashes if you miss the middle dits. Context tells you: BT appears between thoughts, not inside words.
K vs KN — go ahead, anyone vs only you
K invites anyone to answer. KN invites one named station. In a pileup, when several stations are calling at once, KN with a partial callsign tells one station to reply and everyone else to wait. Answering someone else’s KN is poor operating.
AS — stand by
AS means “wait a moment.” The other station should stay quiet until you come back — don’t answer an AS with your callsign.
BK — break in
BK hands the contact over fast, without the full callsign exchange. Useful in a quick back-and-forth between two stations that already know each other.
CL — closing station
CL goes at the very end, after your final callsign: “…SK [callsign] DE [callsign] CL.” It means you’re going off the air. You won’t hear CL in the middle of a contact.
R — received
R near the start of your transmission means “I copied your last transmission.” It is the Morse equivalent of “roger.”
SOS — the distress prosign
SOS is sent as one continuous signal — no gaps between S, O, and S. It is not an acronym; it doesn’t stand for “save our souls” or anything else. It was chosen because the pattern is unmistakable. Use it only for real, imminent danger to life or property. Sending a false distress call is illegal in most countries and can divert real rescue resources.
HH — error / correction
Sent a wrong character? Send HH (eight dits) and then the correct text. No need to restart the whole message — HH says “ignore what I just sent.”
CT/KA and SN/VE — the ones everyone forgets
CT (also KA) opens a transmission: “attention, a message follows.” SN (also VE) means “understood” or “verified.” You won’t hear them in every contact, but you’ll meet them in formal traffic and nets.
Q-Codes: The Complete Table
A Q-code is three letters starting with Q. Each one packs a whole sentence into three letters, which is why they work across languages: an operator in Japan and an operator in Brazil both know what QTH means. Q-codes began in maritime radio and were standardized by the ITU.
The “?” rule
The same code is a statement without “?” and a question with it. QTH means “My location is…” — QTH? means “What is your location?” Forgetting the “?” flips the meaning: QRL (the frequency is busy) vs QRL? (is the frequency busy?). Always send the “?” when you’re asking.
The 20 Q-codes to know first
| Q-code | As a question (?) | As a statement | Example |
|---|---|---|---|
| QRL | Is the frequency busy? | The frequency is busy. | “QRL?” before transmitting on a new frequency. |
| QRM | Are you troubled by interference? | I am troubled by interference (1–5). | “QRM 4” = severe interference. |
| QRN | Are you troubled by static? | I am troubled by static (1–5). | “QRN 3” = moderate static. |
| QRO | Shall I increase power? | Increase power. | “QRO?” — asking whether to go louder. |
| QRP | Shall I decrease power? | Decrease power. / Operating at low power. | “QRP” is also the name for low-power operating. |
| QRQ | Shall I send faster? | Send faster (…wpm). | “QRQ” when you’re in a hurry. |
| QRS | Shall I send more slowly? | Send more slowly (…wpm). | “PSE QRS” — please slow down. |
| QRT | Shall I stop sending? | Stop sending / closing down. | “MUST QRT” — I have to go. |
| QRU | Have you anything for me? | I have nothing for you. | “QRU?” at net check-in. |
| QRV | Are you ready? | I am ready. | “QRV?” before a contest exchange. |
| QRX | When will you call me again? | I will call you again at… | “QRX 1500” — I’ll call at 3 PM. |
| QRZ | Who is calling me? | You are being called by… | “QRZ?” after a callsign you missed. |
| QSA | What is the strength of my signals? | The strength of your signals is (1–5). | “UR QSA 5” — your strength is 5. |
| QSB | Are my signals fading? | Your signals are fading. | “QSB” on a fluttery band. |
| QSL | Can you acknowledge receipt? | I acknowledge receipt. | “QSL?” — did you copy that? |
| QSO | Can you communicate with…? | I can communicate with… | “QSO” also means a contact itself. |
| QSP | Can you relay to…? | I will relay to… | “QSP W1ABC” — please relay to W1ABC. |
| QSX | Will you listen to… on…? | I am listening to… on… | “QSX 14050” — listening on that frequency. |
| QSY | Shall I change frequency? | Change frequency. | “QSY 5 UP” — move 5 kHz up. |
| QTH | What is your location? | My location is… | “QTH?” — where are you? |
73, 88, and the Number Codes
73 means “best regards.” 88 means “love and kisses.” Both come from the Western Union 92 Code, a numbered shorthand list from the 1800s landline-telegraph era, when telegraph lines were shared and every minute on the wire cost money. 73 started as “accept my compliments” and softened into “best regards”; 88 kept its meaning. You’ll hear 73 at the end of nearly every contact — it is the standard friendly sign-off. 88 is personal: between spouses, family, or close friends.
The “73s” debate
Purists say “73” is already plural — “best regards” — so “73s” reads as “best regardses.” You’ll still hear “73s” on nets and in group contacts, where operators use it to mean “best regards to everyone.” Both forms are understood. If you want to be strictly correct, send “73.” If you’re closing a net with many stations, “73s” will not confuse anyone.
30 and other number codes
- 30 — “the end” or “no more.” Used at the end of a message or story (old press-wire usage).
- Non-radio uses: 73 has escaped radio — you’ll see it in texts, emails, and forum posts between hams. 88 stays personal.
Everyday CW Abbreviations You’ll Meet
These aren’t prosigns — they’re shortened words, sent with normal letter spacing. You’ll meet them in every contact.
| Abbreviation | Meaning |
|---|---|
| DE | From / this is |
| ES | And |
| OM | Old man (a fellow operator) |
| UR | Your / you’re |
| TNX | Thanks |
| TU | Thank you |
| FB | Fine business (very good) |
| WX | Weather |
| OP | Operator |
| RIG | Station equipment |
| GN | Good night |
| GM | Good morning |
| HW | How / how copy |
| CPY | Copy (I hear you / I understand) |
| PSE | Please |
| AGN | Again |
| FER | For |
How to Send Prosigns Correctly
The rule is the one from the top of this article: no gaps inside a prosign. Here’s how that plays out in practice.
Timing contrast
Normal letters are separated by a 3-unit gap. Inside a prosign, there is no letter gap — the elements run with 1-unit spacing, the same as inside a single character. If you’re new to timing, the learn guide covers the full spacing rules.
Common mistakes
| Mistake | What happens | Fix |
|---|---|---|
| Sending BT as two letters (B, pause, T) | Listener hears “B T” — meaningless | Key BT as one pattern, no pause |
| Spacing out SK (… pause -.-) | Listener hears “S K” — not “end of contact” | Key SK as one pattern |
| Forgetting “?” on Q-codes | QRL (busy) vs QRL? (asking) — opposite meanings | Send “?” when asking |
| Sending SK mid-contact | Tells the other station you’re done | Use AR for end of message; save SK for the very end |
| Answering someone else’s KN | You transmit over the station they called | Wait for a general K or your own callsign |
| Sending CQ as one run-together signal | CQ is two letters with normal spacing | Send C, gap, Q |
Practice sending prosigns with the Morse code machine.
A Real Conversation, Decoded
Which signal do you send when? Start with CQ. When someone answers, send their callsign, then DE, then yours, then K or KN. Exchange information with BT between thoughts. End a message with AR. End the whole contact with 73, SK, and CL.
Here is a short contact between two fictional operators, decoded line by line. Nothing here is a real transmission — it is an example built to show how the signals fit together.
“Calling any station, this is W1ABC, go ahead.” (CQ = general call, DE = this is, K = anyone may answer.)
“W1ABC, this is W2XYZ, go ahead.” (W2XYZ answers.)
“W2XYZ, this is W1ABC. [Break.] Your signal report is 599. [Break.] My name is Sam. [Break.] My location is Boston. [Break.] How do you copy? Go ahead, only you.” (BT separates thoughts; RST = signal report; 5NN = 599 in cut numbers; HW CPY? = how do you copy?; KN = only the named station answers.)
“W1ABC, this is W2XYZ. Received. [Break.] Your report is 599. [Break.] My name is Jo. [Break.] My location is Denver. [Break.] Thanks for the contact, best regards. End of contact. W1ABC, this is W2XYZ, closing station.” (R = received; FER = for; TNX = thanks; 73 = best regards; SK = end of contact; CL = closing.)
Want to hear a real signal? Run Morse audio through the audio decoder and watch it turn into text.
RST signal reports
RST is three numbers: Readability (1–5), Strength (1–9), Tone (1–9). 599 means perfectly readable, extremely strong signal, purest tone — the best report you can get. Operators shorten it with cut numbers: 5NN means 599, because N stands for 9. Cut numbers replace long digits with short letters: 1=A, 2=U, 3=V, 4=4, 5=E, 6=6, 7=G, 8=D, 9=N, 0=T. You’ll hear “5NN” far more often than “599” because it’s faster to send.
How to Learn Prosigns: Start With 12
You don’t need to memorize all of them at once. Learn these 12 first, in this order — emergency and control signals first, then the everyday ones:
- SOS — distress
- AR — end of message
- SK — end of contact
- CQ — calling any station
- K — go ahead
- KN — go ahead, named station only
- BT — break / separator
- AS — stand by
- BK — break in
- CL — closing station
- R — received
- HH — error / correction
After those, add CT/KA, SN/VE, and AA. Then the Q-codes — start with QTH, QSL, QRZ, QRM, QRN. Practice in real exchanges (or the annotated conversation above), not by staring at the table — recognition comes from hearing the patterns in context. If you hear a code you don’t know, look it up in the tables above — don’t guess.
FAQ
What is a prosign in Morse code?
A prosign (procedural signal) is two or three letters sent as one continuous character to give an instruction, like <AR> for “end of message.” It’s not a word and doesn’t spell anything — it’s a signal.
What is a Q-code?
A three-letter code starting with Q that packs a whole sentence into three letters, like QTH (“my location is…”). Q-codes work across languages because every operator learns the same meanings.
What’s the difference between a prosign and a Q-code?
A prosign is sent as one run-together character and gives an instruction (end of message, stand by). A Q-code is sent as normal letters and asks a question or makes a statement (where are you / my location is…). Different jobs, different sending rules.
What’s the difference between AR and SK?
AR ends a message; SK ends the whole contact. You’ll send AR many times in a contact and SK once, at the very end.
Is SOS a prosign or a Q-code?
A prosign. It’s sent as one continuous signal (…—…) and means distress. It’s not a Q-code and not an acronym.
What does 73 mean in Morse code?
“Best regards.” It’s the standard friendly sign-off at the end of a contact. It comes from the old 92 Code, not from Morse code itself.
What does 88 mean?
“Love and kisses.” Personal — used between spouses, family, or close friends, not in ordinary contacts.
Is “73s” correct?
Strictly, no: 73 already means “best regards” (plural), so 73s reads as “best regardses.” In practice, many operators use 73s on nets to mean “best regards to everyone,” and everyone understands it.
What does SK mean — and what is a “silent key”?
<SK> sent as one signal means “end of contact.” “Silent key” is a separate term for a deceased operator, also written SK in text. Same letters, different meanings — context tells you which.
How do you send a prosign?
Key the whole pattern with no pause between the letters. If you pause, the listener hears separate letters and the meaning is lost.
How do you type a prosign correctly?
In print, use an overbar over the letters or angle brackets: <AR>. On a plain keyboard, <AR> is the standard way. Keyer software usually maps punctuation keys to prosigns — check your program’s mapping.
Why does my decoder show = (or + or () instead of BT (or AR or KN)?
Decoders map run-together patterns to the nearest text character: BT becomes =, AR becomes +, KN becomes (, AS becomes &. Your decoder is working correctly — it’s showing you the prosign in text form.
How do I tell BT apart from two dashes when listening?
BT is dah-di-di-di-dah — it has three dits in the middle. Two dashes would be dah-dah with no dits. Listen for the dits, and use context: BT appears between thoughts, not inside words.
Do I need to memorize all prosigns to operate CW?
No. Learn the 12 in the “Start With 12” section and you’ll handle most contacts. Add the rest as you meet them.
How many prosigns are there?
There is no single official count. The working set most operators use is about 15, plus a few rare ones for formal traffic (like AA and DDD). Learn the 12 first; the rest can wait.
Why is SOS sent without spaces?
Because SOS is a prosign, and prosigns are sent as one continuous character. The no-gap pattern is what makes it unmistakable — and what separates it from the letters S, O, S.
Are prosigns the same in every language?
Prosigns and Q-codes are international — they’re standardized by the ITU and mean the same thing everywhere. Everyday abbreviations (like OM) lean English but are used worldwide.
What does RST 599 mean? What is 5NN?
RST is Readability (1–5), Strength (1–9), Tone (1–9). 599 is a perfect report. 5NN is the same report in cut numbers, where N stands for 9.
Do prosigns work on voice radio too, or only Morse?
Prosigns are Morse/CW signals. On voice, operators use prowords instead — “over,” “out,” “roger,” “wilco.” Q-codes and 73, though, are used on voice too.
Try a code in the translator, look up the SOS page for the full distress-signal guide, and follow the learn guide for the complete path from your first letter to your first real contact. Starting from zero? Read How to Learn Morse Code Fast first.
