Morse Code Prosigns

Learn AR, SK, BT, K, KN and other procedural Morse signals with meanings, audio, spacing rules, and examples.

Send continuously: angle brackets such as <AR> mean the component letters are joined with no normal three-unit letter gap.

Common Morse Prosigns and Meanings

Operational signals used to control a Morse contact or message.

SignalContinuous patternMeaningWhen it is usedAudio
<AR>.-.-.End of messageNo more text follows in this message.
<AS>.-...WaitPause while keeping the frequency in use.
<BT>-...-Separator / new paragraphSeparates sections or thoughts.
<HH>........ErrorEight dits indicate that the preceding copy should be disregarded.
<K>-.-Invitation to transmitAny station may reply.
<KN>-.--.Named station onlyOnly the station called should reply.
<SK>...-.-End of contactThe radio contact or work is finished.
<SOS>...---...Distress signalA continuous emergency signal; conventionally listed with prosigns.

What Are Morse Code Prosigns?

Morse code prosigns are procedural shortcuts. They tell the receiving operator what happens next—wait, reply, separate text, end the message, or end the contact. A prosign may look like two letters on paper, but it is transmitted as one uninterrupted pattern.

Prosign Spacing Versus Normal Letters

Normal A R is .- .-., with a three-unit character gap. The AR prosign is .-.-., with only the one-unit element gaps inside the continuous signal. That timing difference changes the meaning.

Operating Example

A short exchange might end its message text with <AR>, invite a reply with K, and finish the completed contact with <SK>. Procedures vary by service and operating convention, so use the rules applicable to your activity.

End, Reply and Control Signals

End Signals

<AR> ends a message. <SK> ends the contact or work.

Reply Signals

K invites any station. <KN> restricts the reply to the named station.

Control Signals

<AS> means wait, <BT> separates text, and <HH> marks an error.

SOS and Procedural Signals

SOS is the internationally recognised distress signal ...---..., sent as one continuous sequence. It is often displayed alongside prosigns, although its function is specifically distress rather than routine message procedure. See the dedicated SOS Morse code guide for history, timing and emergency context.

Frequently Asked Questions

A prosign is a procedural signal made from letters sent together as one continuous Morse character, with no normal letter gap between them.