Morse Code for Ham Radio: A Beginner's Guide to CW

CW is Morse code sent over a radio, and among radio amateurs it is the one place Morse is still used every day by people who choose it. The transmitter puts out a single steady carrier and a key switches it on and off. The message is in the pattern of on and off.

You do not need Morse to get an amateur radio licence any more. Most countries dropped that requirement years ago. You do need a licence to transmit, and you need nothing at all to listen, which is where every CW operator starts.

Most contacts are short and run to the same script: a call, an answer, a signal report, a name, a location, a sign-off. Twenty or so tokens cover almost all of it, which is why a beginner can work a real station long before they can hold a conversation.

Hearing beats reading here. MorseLab turns any text into a tone, a torch flash or a vibration, free and offline.

What CW means, and why nothing audible leaves the antenna

CW stands for continuous wave, which sounds strange for a mode made entirely of interruptions. The name is historical. The earliest transmitters were spark gaps and threw a broad, rough, damped burst of noise across a wide chunk of spectrum. The continuous wave was the improvement: one clean, steady frequency. Keying that carrier on and off gave you Morse, and the name stayed.

The part that matters for a beginner is that the transmitter sends no tone. It sends a bare carrier, present or absent. The beep is made in your receiver. Switched to CW mode, it mixes the incoming carrier against an internal oscillator, and the difference between the two frequencies comes out of the speaker as an audio note.

Two things follow from that, and both confuse people on their first day.

You choose the pitch. Tune across a CW signal and its note slides from high to low and back. Nothing about the transmission changed. Most operators settle on a note somewhere in the middle of their hearing, often around 600 Hz, and leave it there, because the ear learns rhythms faster when the sound is the same every session.

Answering someone means matching pitch. To reply you must transmit on their frequency, and you find it by tuning until their note matches the pitch your own radio makes when you key it, called the sidetone. Operators say they are zero-beating the other station. Get it wrong by a few hundred hertz and you are calling next to them rather than on them.

Why CW gets through when voice does not

A CW signal is very narrow. Speech has to carry a couple of thousand hertz of audio; a keyed carrier needs a fraction of that, so the receiver can close its filter to a narrow slit and throw away nearly all the noise arriving alongside.

Then there is the ear, which is unreasonably good at picking a steady tone out of hiss. A note you can barely measure is still a note you can copy. Put the two together and CW contacts happen at power levels where voice would be hopeless, which is why low-power operating is mostly a CW activity and why the mode is still in daily use rather than in a museum. There is more on where else Morse survives in is Morse code still used.

Do you need Morse code to get a licence?

Three questions get tangled together here, so take them apart.

Do you need a licence to transmit? Yes, everywhere. Amateur radio runs on licensed access to shared spectrum, and your national telecom regulator sets the exam.

Does the exam test Morse? Almost certainly not. The requirement was dropped from most amateur licences years ago, which is exactly why CW is now something people take up on purpose rather than endure to pass a test.

Do you need anything to listen? No. Browser-based receivers put real shortwave radios online. Tune one, park in the CW part of a band and listen to real operators tonight. That is the best practice material there is, because real signals fade, drift and get stepped on, and a clean audio file never does.

The words on the air

CW conversation is compressed to an extreme. It has to be, because a single letter takes about half a second to send at moderate speed, so the language has been shaved down over a century of use. Perhaps twenty tokens carry most of an ordinary contact.

Written down, a dot is . and a dash is -. Letters are separated by a space and words by /, so -.-. --.- is CQ. Spoken, a dot is a dit and a dash is a dah, which is how operators say the rhythms aloud.

CQ is the one to recognise first. It is a general call, sent to nobody in particular, and it means the operator is looking for a contact. A common form is three CQs, then DE, then the callsign twice, then K:

-.-. --.- / -.-. --.- / -.-. --.- / -.. . / -.-. .- .-.. .-.. / -.-. .- .-.. .-.. / -.-

Replace the two -.-. .- .-.. .-.. groups with your own callsign; CALL is standing in for it here. That whole call is 229 units long, and at 20 words per minute one unit is 60 ms, so it takes about 13.7 seconds to send. Time it once and you will understand why nobody says "thank you very much" on CW.

Q-codes: three letters instead of a sentence

Q-codes are the other half of the vocabulary. Each is three letters beginning with Q and stands for a whole sentence. They came out of commercial and maritime radio and they survive because they are short and language-independent, which matters when the station answering you speaks none of your languages.

Add a question mark and the code is a question; leave it off and it is a statement. QRS? asks whether you should send more slowly. QRS asks the other operator to.

Two of these will be useful in your first week. QRS PSE is the polite way to ask someone to slow down, and every decent operator will:

--.- .-. ... / .--. ... .

And AGN? asks for a repeat, which is not an admission of failure. Experienced operators send it constantly:

.- --. -. ..--..

The full set, and how Q-codes differ from the NATO phonetic alphabet, is in prosigns and Q-codes.

Prosigns: the punctuation of a contact

A prosign is a procedure signal sent as one unbroken run, with no letter gaps inside it. That is the whole trick: the same elements, welded together, become a different symbol.

Look at those against the punctuation table and something clicks: AR is the same run of elements as +, BT the same as =, and KN the same as (. They are not coincidences. The prosigns came first and the punctuation marks were fitted to spare patterns. Plenty of operators write BT as = when they type a message out, and it is sent identically.

KN is worth learning early because it is a small courtesy with a real meaning. K ends your transmission and invites anybody to answer. KN says you want to hear only the station you were already talking to.

SOS belongs on this list for accuracy rather than practice. It is a prosign, ...---..., nine elements sent with no gaps between the groups, and sending S, O and S as three separate letters is a different signal. It does not stand for "Save Our Souls" or "Save Our Ship". Those are backronyms invented long after the pattern was chosen for being unmistakable and easy to send. The maritime distress role passed to GMDSS decades ago, so you will not hear it on the amateur bands; the full story is here.

Signal reports, and the numbers people cut short

Every contact includes a signal report in the RST system: readability, strength, tone, in that order.

So 599 means perfectly readable, very strong, pure tone. It is sent so often that it has become close to a greeting, which is a fair criticism of it, but 339 for a genuinely weak, rough signal is real information and worth sending honestly.

Numbers are expensive in Morse. Every digit is five elements. So operators substitute letters with the same shape but fewer elements, called cut numbers.

That arithmetic is the whole reason the habit exists. A full 599 runs 49 units including the gaps between characters; 5NN runs 25. At 25 words per minute one unit is 48 ms, so the report drops from 2.35 seconds to 1.2. Over a few hundred contacts that is real time.

..... ----. ----.
..... -. -.

The first line is 599, the second is 5NN. They mean the same thing. All ten digits and the pattern behind them are in numbers and punctuation.

A first contact, line by line

Here is an ordinary short exchange. CALL stands in for the callsign of the station making the call and OTHERCALL for the one answering; swap in real callsigns and this is what most contacts look like.

The information half of step 3, which is the line worth copying and playing back until it is familiar:

..- .-. / .-. ... - / ..... ----. ----. / ..... ----. ----. / -. .- -- . / -... .. -- .- .-.. / -... .. -- .- .-.. / --.- - .... / -. . .--. .- .-.. / .... .-- ..--..

That is your report, your name and where you are, then HW? asking how well the other operator is receiving you. Notice what is repeated: the report and the name go twice, because those are the parts the other operator has to write down, and a fade at the wrong moment costs you a repeat request. The rest goes once.

And the sign-off:

- ..- / --... ...-- / . ... / --. .-.. / -.. . / -.-. .- .-.. .-.. / ...-.-

TU 73 ES GL DE CALL, then SK sent as one unbroken prosign. If you can send and copy those two lines, you can complete a contact. Everything else is conversation, and conversation comes later.

Some operators want exactly this and nothing more. Others settle in for half an hour about the weather, the antenna in the garden and the state of their knees. That longer version is called a ragchew, and it is where the mode is at its best.

Speed, and the arithmetic under it

Speed is measured in words per minute against the reference word PARIS, which including the word gap after it is exactly 50 units long. From that comes the one formula worth memorising:

Dot length in seconds = 1.2 ÷ WPM.

The gap between those rows is not a difficulty setting; it is a change in what you are doing. Up to about 15 WPM most people are still writing letters on paper. Above roughly 20 they have stopped writing and started hearing words. That transition is called head copy, it is the actual skill, and it arrives on its own rather than on a schedule. Hearing shapes instead of counting dots is what CW is built on, and the full timing arithmetic is in timing and WPM.

Call at the speed you can read, not the speed you can produce. Sending is always easier than receiving, and if you call fast, someone will answer fast and you will lose the contact.

Keys: what you actually press

You have four choices, and the first two cover almost everybody.

A straight key puts the ratio in your hand, and a badly sent straight-key character is instantly audible, which is useful feedback. A paddle with a keyer removes the problem: press left for a stream of dots, right for dashes, both together for alternating elements, which is called iambic or squeeze keying.

Whichever you use, the rhythm the other operator hears is the rhythm you learned by ear. Dot 1 unit, dash 3, gap inside a character 1, between characters 3, between words 7. Poor sending is nearly always a spacing problem rather than a speed problem: the characters are fine, the gaps are squeezed, words run together and you get asked for a repeat.

Getting ready without wasting months

You cannot learn to copy by ear in a day. You can memorise the chart in a day, and those are different skills. Copying takes weeks of daily practice, and how many weeks depends on how many sessions you actually run rather than how many days pass. Nobody can give you an honest number.

What is reliable is the shape of the practice.

• Learn by sound from the first minute. Do not study the printed alphabet chart and translate in your head. That habit works to about 10 WPM and then collapses.
• Keep the characters fast and stretch the gaps. A slow character has a different rhythm and you will unlearn it later.
• Drill the CW vocabulary itself. CQ, DE, K, RST, 599, 5NN, 73, the Q-codes above and the digits. Those tokens are most of what you will hear, and practising them directly beats waiting for random letters to cover them.
• Copy callsigns. They are the hardest part of a real contact, because a callsign is a random string with no context to guess from.
• Listen to real signals on a web receiver before you ever key up.

Two names come up constantly and are usually presented as rivals, which is wrong. Koch is about order and progression: start with two characters at full target speed and add another only once you are copying at 90% accuracy, never slowing down. Farnsworth is about spacing: full-speed characters with stretched gaps between them so you have time to think. They change different variables, so they combine, and the combination is the normal recommendation. Koch vs Farnsworth takes it apart properly, and how to learn Morse code has the full plan.

I built MorseLab partly for this stage, when you know the letters and are not yet on the air. It runs Koch lessons that add one character at a time at full character speed, keeps the reference you reach for most (the chart, the prosigns, the Q-codes and the NATO alphabet) in one place, and plays any text back as a tone, so you can hear a callsign or a whole CQ call rather than read it. It also decodes Morse audio through the microphone, which is a blunt but honest check on your own sending: hold it to your practice oscillator and see whether it reads back what you meant. On a real off-air signal, with fading and interference, expect it to struggle where your ear would too. It runs offline, so a train with no signal is a practice session. The limits of machine decoding are covered in the decoder guide.

Common mistakes

Squeezing the gaps. Most bad CW is correctly formed characters with too little silence between them. The gaps are 1, 3 and 7 units, and the 7 is the one people cut.

Writing dots and dashes on paper. Write the letter or write nothing. Putting -.- on the page and working out afterwards that it was K trains the exact habit you need to lose.

Treating a repeat request as a failure. AGN? and QRS PSE are normal traffic. Every operator sends both.

Learning the chart and stopping there. The chart takes a day. The ear takes weeks, and only the ear gets you a contact.

Waiting for perfection before your first call. You need about fifteen characters, the exchange above and the nerve to send it once. Slow, clean sending is welcome everywhere.

Ignoring the band plan. CW has its own segment on each band by convention. Check the plan your regulator or national society publishes before you transmit.

Questions people ask

What does CW stand for in ham radio?

Continuous wave. It is the mode in which a steady radio carrier is switched on and off to send Morse code, and it got the name to distinguish it from the broad, damped bursts thrown out by the spark transmitters that came before it.

Do I need to know Morse code to get a ham radio licence?

No. The Morse requirement was removed from most amateur licences years ago, so you can qualify and operate without ever sending a dot. You still need the licence itself to transmit, and CW is now something operators learn because they want to rather than to pass a test.

How fast do ham radio operators send CW?

A wide range. Beginners call at 10 WPM and are answered at 10 WPM. Everyday conversation sits around 15 to 20, contest work runs 25 to 40. The dot length is 1.2 ÷ WPM seconds, so 20 WPM is a 60 ms dot and 40 WPM is a 30 ms dot.

What is the minimum I need to know for a first CW contact?

The letters and digits by ear, plus about a dozen tokens: CQ, DE, K, KN, R, RST, 599, NAME, QTH, TU, 73 and SK. With those you can run the exchange written out above from the opening call to the sign-off.

What does 73 mean, and what about 599?

73 is best wishes, a leftover from an old numeric code list, and it ends almost every contact. 599 is a signal report: readability 5 out of 5, strength 9 out of 9, tone 9 out of 9. It is often sent whether or not it is true.

Can I listen to CW without a licence?

Yes. Receiving needs no licence in most places, and browser-based shortwave receivers let you tune real bands from any device. Listening to live signals, with their fading and interference, is better practice than any clean audio file.

What is the difference between a straight key and a paddle?

A straight key is one lever and you time every dot, dash and gap yourself. A paddle has two levers driving an electronic keyer that produces perfectly timed elements, so above roughly 15 WPM it is much easier on the hand and much easier on the person copying you.

Why do CW operators use Q-codes instead of words?

Because a Q-code replaces a sentence with three letters, and every letter costs real time on the air. They are also language-independent, which matters when the station answering you shares no spoken language with you.

Is CW still worth learning?

That depends on what you want, but the technical argument holds: a narrow keyed carrier gets through at power levels and signal strengths where voice cannot, which is why low-power and portable operators keep using it. The rest of the answer is that it is a skill, and skills are their own reason.

Get it: MorseLab — free on iPhone and Android. The link opens your own app store.

Keep reading

• Prosigns, Q-Codes and the NATO Alphabet — the full shorthand around Morse, in detail.
• Morse Code by Sound — hearing characters as rhythms, which is the skill CW runs on.
• Koch vs Farnsworth — why they combine rather than compete.
• Morse Code Timing and WPM — the 1 : 3 : 1 : 3 : 7 ratio and the PARIS standard.
• Is Morse Code Still Used? — where it survives outside amateur radio.