View source for Prosigns for Morse code

{{Short description|Predefined shorthand signals}}
[[File:L-Telegraph1.png|thumb|right|200px|Diagram of a [[telegraph key]] used to send messages in Morse code]]
'''Procedural signs''' or '''prosigns''' are shorthand signals used in [[Morse code]] telegraphy, for the purpose of simplifying and standardizing procedural protocols for landline and radio communication. The procedural signs are distinct from conventional [[Morse code abbreviations]], which consist mainly of [[brevity code]]s that convey messages to other parties with greater [[data compression|speed]] and [[ambiguity|accuracy]]. However, some codes are used ''both'' as prosigns and as single letters or punctuation marks, and for those, the distinction between a prosign and abbreviation is ambiguous, even in context.

==Overview==
In the broader sense prosigns are just standardised parts of short form radio protocol, and can include any abbreviation. Examples would be '''{{sc|K}}''' for "okay, heard you, continue" or '''{{sc|R}}''' for "message, received".<ref name=ITU_MC_Rec/><ref name=ARRL_Send_CW/> In a more restricted sense, "prosign" refers to something analogous to the nonprinting [[control characters]] in [[teleprinter]] and computer [[character set]]s, such as [[Baudot code|Baudot]] and [[ASCII]]. Different from abbreviations, those are universally recognizable across language barriers as distinct and well-defined [[semiotics|symbols]].

At the coding level, prosigns admit any form the Morse code can take, unlike abbreviations which have to be sent as a sequence of individual letters, like ordinary text. On the other hand, most prosigns codes are much longer than typical codes for letters and numbers. They are individual and indivisible [[code points]] within the broader Morse code, fully at par with basic letters and numbers.

The development of prosigns began in the 1860s for wired telegraphy. Since telegraphy preceded voice communications by several decades, many of the much older Morse prosigns have acquired precisely equivalent [[Proword|pro''words'']] for use in more recent [[radio telephony|voice protocols]].

Not all prosigns used by telegraphers are standard: There are regional and community-specific variations of the coding convention used in certain radio networks to manage transmission and formatting of messages, and many unofficial prosign conventions exist; some of which might be redundant or ambiguous. One typical example of something which is not an officially recognized prosign, but is yet fairly often used in Europe, is one or two freely timed dits at the end of a message, {{nobr|&nbsp; {{math|{{sc|'''I'''}} &nbsp; {{sc|'''I'''}} }} &nbsp;}} or {{morse|dot|dot}} {{morse|dot|dot}}; it is equivalent to the proword ''OUT'', meaning "I'm done; go ahead". However the ''official'' prosign with the same meaning is {{sc|'''{{overline|AR}}'''}}, or {{morse|dot|dash|dot|dash|dot}}, which takes a little longer to send.<ref name=ARRL_Oper_Man/><ref name=ARRL_Send_CW/>

===Representation in printed material===
Even though represented as strings of letters, prosigns are rendered without the intercharacter [[comma code|commas or pauses]] that would occur between the letters shown, if the representation were (mistakenly) sent as a sequence of letters: In printed material describing their meaning and use, prosigns are shown either as a sequence of dots and dashes for the sound of a telegraph, or by an overlined sequence of letters from the [[International Morse Code]], which when sent ''without'' the usual spacing, sounds like the prosign symbol.

The best-known example of the convention is the standard [[distress call]] preamble: [[SOS|{{sc|'''{{overline|SOS}}'''}}]]. As a prosign it is not really composed of the three separate letters ''S'', ''O'', and ''S'', (in International Morse: {{morse|dot|dot|dot}} {{morse|dash|dash|dash}} {{morse|dot|dot|dot}}) but is run together as a single symbol {{morse|dot|dot|dot|dash|dash|dash|dot|dot|dot}}, which is a [[semiology|sign]] in its own right.

==History==
In the early decades of telegraphy, many efficiency improvements were incorporated into operations. Each of the early versions of Morse code was an example of that: With only one glaring exception (Intl. Morse '''{{sc|O}}'''), they all encoded more common characters into shorter keying sequences, and the rare ones into longer, thus effecting online [[data compression]]. The introduction of Morse symbols called ''procedural signs'' or ''prosigns'' was then just a logical progression. They were not defined by the developers of Morse code, but were gradually introduced by telegraph operators to improve the speed and accuracy of high-volume message handling, especially those sent over that era's problematic long distance communication channels, such as [[Submarine communications cable|transoceanic cables]] and later [[longwave]] [[wireless telegraphy]].

Among other prosign uses, improvement in the legibility of written messages sent by telegraph (telegrams) using white space formatting was supported by the procedural symbols. To become an efficient [[telegraphist|telegraph operator]] it was important to master the Morse code prosigns, as well as the [[Morse code abbreviations|many standard abbreviations]] used to facilitate checking and re-sending sections of text.

==Notation and representations==
There are at least three methods used to represent Morse prosign symbols:  
# Unique dot/dash sequences, e.g. {{morse|dash|dot|dot|dot|dash}} 
# Unique audible sounds, e.g. ''dah di di di dah'' 
# Non-unique printed or written [[Overline|overlined]] character groups,{{efn|
When overlining is not available, the same characters can be written in <angle brackets> or <u>underlined</u>, hence '''{{overline|{{sc|BT}}}}''' ({{morse|dash|dot|dot|dot|dash}}) is equivalent to both <'''{{sc|BT}}'''> and '''<u>{{sc|BT}}</u>'''.
}} e.g. '''{{overline|{{sc|BT}}}}'''

Although some of the prosigns as-written appear to be simply two adjacent letters, ''most'' prosigns are transmitted as [[Digraph (orthography)|digraphs]] that have '''''no''''' pauses between the patterns that represent the "combined" letters, and are most commonly written with a single bar over the merged letters (if more than one single character) to indicate this.<ref name=ITU-R-M-1172/> The only difference between what is transmitted for the Morse code prosign vs. the separate letter signs is the presence or absence of an inter-letter space between the two "dit" / "dah" sequences.
Although the difference in the transmission is subtle, the difference in meaning is gross:
: For example, the unofficial prosign '''{{overline|{{sc|AA}}}}''' ({{morse|dot|dash|dot|dash}}) indicates that the receiving Morse operator should begin a new line,{{efn|
name=AA_ARRL_note|
The prosign {{overline|'''{{sc|AA}}'''}} is only used for multi-line addresses inside message headings of [[American Radio Relay League|ARRL]] batched message format, where sending the more common {{overline|'''{{sc|BT}}'''}} prosign would prematurely terminate the heading.<ref name=ARRL_Send_CW/>
:
The sequence produced by {{overline|'''{{sc|AA}}'''}} {{=}} {{morse|dot|dash|dot|dash}} has also been in non-ITU (hence "unofficial") use in [[German language]] Morse for the letter '''{{sc|Ä}}''', for eastern European railway telegraphy.
}} but the two separate letter sign or abbreviation '''{{sc|AA}}''' ({{morse|dot|dash}}{{morse|dot|dash}}) indicates the voice procedure words ''ALL AFTER'', used to indicate what part of the previously transmitted message needs to be re-transmitted.{{efn|
Only when sent with ship-to-ship signal lights does the abbreviation '''{{sc|AA}}''' have the same meaning as the voice [[procedure word]] ''UNKNOWN STATION''.<ref name=ICS-102/>
}}

Because no letter boundaries are transmitted with the codes counted as ''prosigns'', their representation by two letters is usually arbitrary, and may be done in multiple equivalent ways. Normally, one particular form is used by convention, but some prosigns have multiple forms in common use:
: For example, '''{{overline|{{sc|AA}}}}''' ({{morse|dot|dash}}+{{morse|dot|dash}}) is exactly equivalent to '''{{overline|{{sc|EK}}}}''' ({{morse|dot}}+{{morse|dash|dot|dash}}) and '''{{overline|{{sc|RT}}}}''' ({{morse|dot|dash|dot}}+{{morse|dash}}).

: Although the well-known calling prosign for emergency messages '''{{overline|{{sc|SOS}}}}''' is always represented by the three letters "[[SOS]]", it ''could'' just as well be written '''{{overline|{{sc|VZE}}}}''' ({{morse|dot|dot|dot|dash}}+{{morse|dash|dash|dot|dot}}+{{morse|dot}}), '''{{overline|{{sc|VGI}}}}''' ({{morse|dot|dot|dot|dash}}+{{morse|dash|dash|dot}}+{{morse|dot|dot}}), or even '''{{overline|{{sc|3B}}}}''' ({{morse|dot|dot|dot|dash|dash}}+{{morse|dash|dot|dot|dot}}); all of these render the same single code {{morse|dot|dot|dot|dash|dash|dash|dot|dot|dot}}.

Many Morse code prosigns do not have written or printed textual character representations in the original source information, even if they do represent characters in other contexts. For example, when embedded in text the Morse code sequence {{morse|dash|dot|dot|dot|dash}} represents the "double hyphen" character (normally "'''='''", but also {{nobr|"'''– –'''"}}).<ref name=ITU_MC_Rec/> When the same code appears alone it indicates the action of spacing down two lines on a page in order to create the white space indicating the start of a new paragraph<ref name=ARRL_Send_CW/> or new section in a message heading.<ref name=ITU_MC_Rec/> When used as a prosign, there is no actual written or printed character representation or symbol for a new paragraph (i.e. no symbol corresponding to "{{big|[[¶]]}}"), other than the two-line white space itself.

Some prosigns are in unofficial use for special characters in languages other than [[English language|English]], for example {{overline|'''{{sc|AA}}'''}} is used unofficially for both the "next line" prosign{{efn|name=AA_ARRL_note}} and for "'''{{sc|Ä}}'''",<ref name="Deutsch-Österreich-Telegr-1851"/><ref name=Smithsonian-Report-1879/> neither of which is in the international standard.<ref name=ITU_MC_Rec/> Other prosigns are officially designated for both characters and prosigns, such as {{overline|'''{{sc|AR}}'''}} equiv. "'''+'''", which marks the end of a message.{{efn|name=AR_EOM}}<ref name=ITU_MC_Rec/> Some genuinely have only one use, such as {{overline|'''{{sc|CT}}'''}} or the equivalent {{overline|'''{{sc|KA}}'''}} ({{morse|dash|dot|dash|dot|dash}}), the International Morse prosign that marks the start of a new transmission<ref name=ITU_MC_Rec/> or new message.<ref name=ARRL_Send_CW/>

== International Morse code ==
The procedure signs below are compiled from the official specification for Morse Code, ITU-R M.1677, International Morse Code,<ref name=ITU_MC_Rec/> while others are defined the [[ITU Radio Regulations|International Radio Regulations for Mobile Maritime Service]], including ITU-R M.1170,<ref name=ITU-R-M-1170/> ITU-R M.1172,<ref name=ITU-R-M-1172/> and the Maritime [[International Code of Signals]],<ref name=ICS-102/> with a few details of their use appearing in [[ACP 131]],<ref name=ACP131F/> which otherwise defines [[operating signals]], not procedure signals.

=== Prosigns ===
The following table of prosigns includes '''{{sc|K}}''' and '''{{sc|R}}''', which could be considered either abbreviations (for "okay, go ahead", and for "received") or prosigns that are also letters. All of the rest of the symbols are not letters, but in some cases are also used as punctuation.

{| class="wikitable"
|+ General-use procedure signs
! Prosign
! Matching voice procedure word
! Code symbol
! Reference
! Explanation
|-
| '''{{overline|AA}}'''
| ''UNKNOWN STATION''
| {{morse|dot|dash|dot|dash}}
|style="text-align:center;"| <ref name=ICS-102/>
| This meaning is '''''only''''' used for directional signal lights.<ref name=ICS-102/> It has no official use in radio telegraphy,<ref name=ITU_MC_Rec/> where it is ''unofficially'' used to represent an accented letter '''{{sc|Ä}}''' or '''{{sc|Á}}''',<ref name="Deutsch-Österreich-Telegr-1851"/><ref name=Smithsonian-Report-1879/> or the prosign for "next line", and then only when it is embedded inside a heading section in amateur traffic.<ref name=ARRL_Send_CW/>
|-
| '''R'''
| ''ROGER''
| {{morse|dot|dash|dot}}
|style="text-align:center;"| <ref name=ITU-R-M-1172/><ref name=ARRL_Send_CW/>
| Means the last transmission has been received, but does ''not'' necessarily indicate the message was understood or will be complied with.<br/>{{Listen|filename=R morse code.ogg|title={{morse|dot|dash|dot}}|plain=yes}}
|-
| '''K'''
| ''OVER''
| {{morse|dash|dot|dash}}
|style="text-align:center;"| <ref name=ITU_MC_Rec/><ref name=ARRL_Send_CW/>
| Invitation to transmit after terminating the call signal. (e.g. {{morse|dot|dash|dot|dash|dot}}{{morse|dash|dot|dash}}).<br/>{{Listen|filename=K morse code.ogg|title={{morse|dash|dot|dash}}|plain=yes}}
|-
| '''{{overline|AR}}'''
| ''OUT''
| {{morse|dot|dash|dot|dash|dot}}
|style="text-align:center;"| <ref name=ITU-R-M-1172/><ref name=ITU_MC_Rec/><ref name=ARRL_Send_CW/>
| End of transmission / End of message / End of telegram.{{efn|name=AR_EOM|
{{overline|'''{{sc|AR}}'''}} was used to mark the end of individual telegrams within a batched-message.
}}<br/>(Same as {{overline|'''{{sc|EC}}'''}} "end copy", and character '''+'''.){{efn|
As of 2017 the is a proposal that (perhaps inadvertently) changes {{overline|AR}} protocol.<ref name=Benedktsn-Kjartnsn-2014-09-27/>
}}<br/>{{Listen|filename=Morse Code - Plus.ogg|title={{morse|dot|dash|dot|dash|dot}}|plain=yes}}
|-
| '''{{overline|AS}}'''
| ''WAIT''
| {{morse|dot|dash|dot|dot|dot}}
|style="text-align:center;"| <ref name=ITU-R-M-1170/><ref name=ITU-R-M-1172/><ref name=ITU_MC_Rec/><ref name=ARRL_Send_CW/>
| "I must pause for a few minutes."{{efn|
{{overline|'''{{sc|AS}}'''}} may optionally be followed by the estimated number of minutes of waiting time.
}}
Also means "I am engaged in a contact with another station [that you might not hear]; please wait quietly."<br/>{{Listen|filename=Morse Code - Ampersand.ogg|title={{morse|dot|dash|dot|dot|dot}}|plain=yes}}
|-
| '''{{overline|AS}}''' '''{{overline|AR}}'''
| ''WAIT'' ''OUT''
| {{morse|dot|dash|dot|dot|dot}}<br/>{{morse|dot|dash|dot|dash|dot}}
|style="text-align:center;"| <ref name=ACP124/>
| I must pause for more than a few minutes.
|-
| '''{{overline|VE}}'''
| ''VERIFIED''
| {{morse|dot|dot|dot|dash|dot}}
|style="text-align:center;"| <ref name=ITU_MC_Rec/><ref name=ARRL_Send_CW/>
| Message is verified.<!-- Response to _AS_/WAIT? Research to see if ARRL-specific. --><br/>{{Listen||filename=Morse Prosign - Understood.oga|title={{morse|dot|dot|dot|dash|dot}}|plain=yes}}
|-
| '''?'''
| ''SAY AGAIN?''
| {{morse|dot|dot|dash|dash|dot|dot}}
|style="text-align:center;"| <ref name=ITU_MC_Rec/><ref name=ACP124/>
| When standing alone, a note of interrogation or request for repetition of the immediate prior transmission that was not understood.
When '''?''' is placed ''after'' a coded signal, modifies the code to be a question or request.<br/>{{Listen|filename=Morse Code - Question Mark.ogg|title={{morse|dot|dot|dash|dash|dot|dot}}|plain=yes}}
|-
| '''{{overline|INT}}'''
| ''INTERROGATIVE''
| {{morse|dot|dot|dash|dot|dash}}
|style="text-align:center;"| <ref name=ACP124/><ref name=ACP131F/><ref name=Op-Guide-2009/>
| Military replacement for the '''?''' prosign; equivalent to Spanish [[¿|'''¿''' punctuation mark]]. When placed ''before'' a signal, modifies the signal to be a question/request.<ref name=FM24-6/>{{efn|
1945 procedural use: "The correctness of a short portion of a message may be questioned directly by the receiving operator using the interrogatory prosign {{overline|'''{{sc|INT}}'''}}, but this method should not be used to question a part of a message for which a receipt has been given.<ref name=FM24-6/>
}}
|-
| '''{{overline|HH}}''' ...
| ''CORRECTION''
| {{morse|dot|dot|dot|dot|dot|dot|dot|dot}}
|style="text-align:center;"| <ref name=ITU_MC_Rec/><ref name=ARRL_Send_CW/>
| Preceding text was in error. The following is the corrected text. (Same as {{overline|'''{{sc|IIII}}'''}} or  {{overline|'''{{sc|EEEEEEEE}}'''}}.)<br/> {{Listen||filename=Morse Prosign - Error.oga|title={{morse|dot|dot|dot|dot|dot|dot|dot|dot}}|plain=yes}}
|-
| '''{{overline|HH}}''' '''{{overline||AR}}'''
| ''DISREGARD THIS TRANSMISSION'' ''OUT''
| {{morse|dot|dot|dot|dot|dot|dot|dot|dot}}<br/>{{morse|dot|dash|dot|dash|dot}}
|style="text-align:center;"|
| The entire message just sent is in error, disregard it. (Same as {{overline|'''{{sc|EEEEEEEE}}'''}}&nbsp;{{overline|'''{{sc|AR}}'''}}.){{efn|
The prowords {{overline|'''{{sc|HH}}'''}}&nbsp;{{overline|'''{{sc|AR}}'''}} may ''not'' be used to cancel a message after it has already been completely transmitted, and receipt acknowledged.{{citation needed|date=October 2023}}
}}
|-
| '''{{overline|BT}}'''
| ''BREAK''
| {{morse|dash|dot|dot|dot|dash}}
|style="text-align:center;"| <ref name=ITU-R-M-1172/><ref name=ITU_MC_Rec/><ref name=ARRL_Send_CW/>
| Start new section of message.<br/>Same as character '''=''' or rarely '''– –'''.
|-
| '''{{overline|KA}}'''
| ''ATTENTION''
| {{morse|dash|dot|dash|dot|dash}}
|style="text-align:center;"| <ref name=ITU-R-M-1172/><ref name=ITU_MC_Rec/><ref name=ARRL_Send_CW/>
| Message begins / Start of work / New message<br/>(Starting signal that precedes every transmission session. Sometimes written as {{overline|'''{{sc|CT}}'''}}.)<br/>{{Listen||filename=Morse Prosign - Starting Signal.oga|title={{morse|dash|dot|dash|dot|dash}}|plain=yes}}
|-
| '''{{overline|SK}}'''
| ''OUT''
| {{morse|dot|dot|dot|dash|dot|dash}}
|style="text-align:center;"| <ref name=ITU-R-M-1172/><ref name=ITU_MC_Rec/><ref name=ARRL_Send_CW/>
| End of contact / End of work / Line is now free / {{nobr|Frequency no longer in use}}<br/>(Ending signal that follows every transmission session. Occasionally written {{overline|'''{{sc|VA}}'''}}.)
|}

=== Abbreviations for message handling ===
The following table lists standard abbreviations used for organizing radiotelegraph traffic, however none of them are actual prosigns, despite their similar purpose. All are strictly used as normal strings of one to several letters, never as [[Digraph (orthography)|digraph]] symbols, and have standard meanings used for the management of sending and receiving messages. Dots following indicate that in use, the abbreviation is always followed by more information.

{| class="wikitable"
|+ General-use abbreviations and letter-codes
! Abbrev.
! Matching voice procedure word
! Code symbol
! Reference
! Explanation
|-
| '''DE''' ...
| ''{{grey|[THIS IS]}} FROM''
| {{morse|dash|dot|dot}} {{morse|dot}}
|style="text-align:center;"| <ref name=ITU-R-M-1172/><ref name=ITU_MC_Rec/><ref name=ARRL_Send_CW/>
| Used to precede the name or other identification of the station sending the transmission ([[Morse code abbreviations|Morse abbreviation]]).
|-
| '''NIL'''
| ''NOTHING HEARD''
| {{morse|dash|dot}} {{morse|dot|dot}} {{morse|dot|dash|dot|dot}}
|style="text-align:center;"|
| General-purpose response to any request or inquiry for which the answer is "nothing" or "none" or "not available" ([[Morse code abbreviations|Morse abbr.]]). Also means "I have no messages for you."
|-
| '''CL'''
| ''CLOSING''
| {{morse|dash|dot|dash|dot}} {{morse|dot|dash|dot|dot}}
|style="text-align:center;"| <ref name=ITU-R-M-1172/><ref name=ARRL_Send_CW/>
| Announcing station shutdown ([[Morse code abbreviations|Morse abbr.]]).
|-
| '''CQ'''
| ''CALLING''
| {{morse|dash|dot|dash|dot}} {{morse|dash|dash|dot|dash}}
|style="text-align:center;"| <ref name=ITU-R-M-1172/><ref name=ARRL_Send_CW/>
| General call to any station ([[Morse code abbreviations|Morse abbr.]]).
|-
| '''CP''' ... ...
| ''CALLING FOR''
| {{morse|dash|dot|dash|dot}} {{morse|dot|dash|dash|dot}}
|style="text-align:center;"| <ref name=ITU-R-M-1172/>
| Specific call to two or more named stations ([[Morse code abbreviations|Morse abbr.]]).
|-
| '''CS''' ...
| ''CALLING STATION''
| {{morse|dash|dot|dash|dot}} {{morse|dot|dot|dot}}
|style="text-align:center;"| <ref name=ITU-R-M-1172/>
| Specific call to exactly one named station ([[Morse code abbreviations|Morse abbr.]]).
|-
| '''CS ?'''
| ''WHO ?''
| {{morse|dash|dot|dash|dot}} {{morse|dot|dot|dot}} {{morse|dot|dot|dash|dash|dot|dot}}
|style="text-align:center;"| <ref name=ITU-R-M-1172/>
| What is the name or identity signal of your station? ([[Morse code abbreviations|Morse abbr.]]) In many contexts, the question mark is optional.
|-
| '''WA''' ...
| ''WORD AFTER''
| {{morse|dot|dash|dash}} {{morse|dot|dash}}
|style="text-align:center;"| <ref name=ITU-R-M-1172/><ref name=ARRL_Send_CW/>
| ([[Morse code abbreviations|Morse abbr.]])
|-
| '''WB''' ...
| ''WORD BEFORE''
| {{morse|dot|dash|dash}} {{morse|dash|dot|dot|dot}}
|style="text-align:center;"| <ref name=ITU-R-M-1172/><ref name=ARRL_Send_CW/>
| ([[Morse code abbreviations|Morse abbr.]])
|-
| '''AA''' ...
| ''ALL AFTER''
| {{morse|dot|dash}} {{morse|dot|dash}}
|style="text-align:center;"| <ref name=ITU-R-M-1172/><ref name=ARRL_Send_CW/>
| The portion of the message to which I refer is all that follows the text ... ([[Morse code abbreviations|Morse abbr.]])
|-
| '''AB''' ...
| ''ALL BEFORE''
| {{morse|dot|dash}} {{morse|dash|dot|dot|dot}}
|style="text-align:center;"| <ref name=ITU-R-M-1172/><ref name=ARRL_Send_CW/>
| The portion of the message to which I refer is all that precedes the text ... ([[Morse code abbreviations|Morse abbr.]])
|-
| {{nobr|'''BN''' ... ...}}
| ''ALL BETWEEN''
| {{morse|dash|dot|dot|dot}} {{morse|dash|dot}}
|style="text-align:center;"| <ref name=ITU-R-M-1172/><ref name=ARRL_Send_CW/>
| The portion of the message to which I refer is all that falls between ... and ... ([[Morse code abbreviations|Morse abbr.]])
|-
| '''C'''
| ''CORRECT'' / ''YES'' / ''AFFIRMATIVE'' / ''CONFIRM''
| {{morse|dash|dot|dash|dot}}
|style="text-align:center;"| <ref name=ITU-R-M-1172/><ref name=ARRL_Send_CW/>
| Answer to prior question is "yes". ([[Morse code abbreviations|Morse abbr.]])
|-
| '''N'''
| ''NO'' / ''NEGATIVE''
| {{morse|dash|dot}}
|style="text-align:center;"| <ref name=ICS-102/><ref name=ACP131F/>
| Answer to prior question is "no". ([[Morse code abbreviations|Morse abbr.]])<!-- Double check ITU docs. -->{{efn|When Morse was still being used in aeronautics, the entire word '''{{sc|NO}}''' ({{morse|dash|dot}}{{morse|dash|dash|dash}}) was sent instead of the abbreviation '''{{sc|N}}'''.}}
|-
| '''ZWF''' ...
| ''WRONG''
| {{morse|dash|dash|dot|dot}}{{morse|dot|dash|dash}}{{morse|dot|dot|dash|dot}}
|style="text-align:center;"| <ref name=ACP131F/>
| Your last transmission was wrong. The correct version is ...
|-
| '''QTR ?'''
| ''REQUEST TIME CHECK''
| {{morse|dash|dash|dot|dash}}{{morse|dash}}{{morse|dot|dash|dot}}<br/> {{morse|dot|dot|dash|dash|dot|dot}} 
|style="text-align:center;"| <ref name=ACP131F/>
| Time-check request. / What is the correct time?<br/>(Time is always [[Coordinated Universal Time|UTC]], unless explicitly requested otherwise, e.g. {{sc|'''QTR'''}} [[Hawaii Standard Time|{{sc|'''HST'''}}]] {{sc|'''?'''}})
|-
| '''QTR''' ...
| ''TIME IS''
|{{morse|dash|dash|dot|dash}} {{morse|dash}} {{morse|dot|dash|dot}}
|style="text-align:center;"| <ref name=ACP131F/>
| The following is the correct time in HHMM 24&nbsp;hour format<br/>(The time is always in [[Coordinated Universal Time|UTC]], except in rare cases when it is followed by a 3&nbsp;letter [[time zone]] abrv., e.g. [[Pacific Standard Time|{{sc|'''PST'''}}]].)
|-
| '''BK'''
| ''BREAK-IN''
| {{morse|dash|dot|dot|dot}} {{morse|dash|dot|dash}}
|style="text-align:center;"| <ref name=ITU-R-M-1172/><ref name=ARRL_Send_CW/>
| Signal used to interrupt a transmission already in progress ([[Morse code abbreviations|Morse abbr.]]). [[NATO]] nets use '''{{sc|AX}}'''.<ref name=ACP131F/> Some military networks use {{morse|zerodash}} {{math|≈}} {{overline|'''{{sc|TTTT}}'''}} instead.
|-
| '''CFM'''
| ''CONFIRM'' / ''I ACKNOWLEDGE''
| {{morse|dash|dot|dash|dot}} {{morse|dot|dot|dash|dot}} {{morse|dash|dash}}
|style="text-align:center;"| <ref name=ITU-R-M-1172/><ref name=ARRL_Send_CW/>
| Message received ([[Morse code abbreviations|Morse abbr.]]). (Same as {{sc|'''R'''}}.)
|-
| '''WX''' ...
| ''WEATHER IS''
| {{morse|dot|dash|dash}} {{morse|dash|dot|dot|dash}}
|style="text-align:center;"| <ref name=ITU-R-M-1172/><ref name=ARRL_Send_CW/>
| Weather report follows ([[Morse code abbreviations|Morse abbr.]]).
|-
| '''{{sc|INTERCO}}'''
| ''INTERCO''
(''in-tur-ko'')
| {{morse|dot|dot}} {{morse|dash|dot}} {{morse|dash}} {{morse|dot}} {{morse|dot|dash|dot}}<br/> {{morse|dash|dot|dash|dot}} {{morse|dash|dash|dash}} 
|style="text-align:center;"| <ref name=ICS-102/><ref name=ITU-R-M-1172/>
| Groups of abbreviations from the ''International Code of Signals''<ref name=ICS-102/> follow ([[Morse code abbreviations|Morse abbr.]]).
|}

== Amateur radio National Traffic System ==
For the special purpose of exchanging [[ARRL Radiogram]]s during [[National Traffic System]] nets, the following prosigns and signals can be used, most of which are an exact match with [[ITU-R]] and [[Combined Communications Electronics Board]] (military) standards; a few have no equivalent in any other definition of Morse code procedure signals or abbreviations.
{| class="wikitable"
|+ Table of Morse code prosigns and useful [[Morse code abbreviations]]<ref name=ARRL_Oper_Man/><ref name=ITU_MC_Rec/><ref name=ARRL_Send_CW/>
|-
! Prosign
! Code symbol
! Meaning
! Comments
! Verbalization
! As text
|-
| '''{{overline|AA}}'''
| {{morse|dot|dash|dot|dash}}
| Start new line
| Space down one line; typewritten as [[Carriage Return]], [[Line Feed]] (CR-LF). Only used instead of '''{{overline|{{sc|BT}}}}''' in [[American Radio Relay League|ARRL]] batched messages, where '''{{overline|{{sc|BT}}}}''' would prematurely start a pending next section.<ref name=ARRL_Send_CW/> Also written {{overline|'''{{sc|RT}}'''}}.
| {{small|''di dah di dah''}}
|'''{{sc|Ä}}''', '''{{sc|Á}}'''{{efn|name=non-Latin|Non-ITU Code adopted nationally for languages with letters not used in Latin, English, or Italian.}}
|-
| '''{{overline|AR}}'''
| {{morse|dot|dash|dot|dash|dot|}}
| Message separator, start new message / telegram.<ref name=ITU_MC_Rec/><ref name=ARRL_Oper_Man/><ref name=ARRL_Send_CW/>
|  New Page, space down several lines.<ref name=ARRL_Oper_Man/> Decoder software may show "'''+'''".<ref name=ITU_MC_Rec/> Alternative for "Break" in conversational Morse.<ref name=ARRL_Send_CW/> Also written {{overline|'''{{sc|RN}}'''}}.
| {{small|''di dah di dah dit''}}
| '''+'''<ref name=ITU_MC_Rec/>
|-
| '''{{overline|AS}}'''
| {{morse|dot|dash|dot|dot|dot}}
| Wait<ref name=ITU_MC_Rec/><ref name=ARRL_Oper_Man/>
| Respond with: {{overline|'''{{sc|SN}}'''}}, or characters "'''{{sc|R}}'''" (Received) or "'''{{sc|C}}'''" (Confirmed).<ref name=ARRL_Oper_Man/><ref name=ITU_MC_Rec/>
| {{small|''di dah di di dit''}}
| '''&'''{{efn |name=nonStdUS|Proposed double-use as punctuation {{underline|a}}mper{{underline|s}}and; non-standard. Abbreviation "'''{{sc|E{{hair space}}S}}'''" is typically used instead.}}
|-
| '''{{overline|BT}}'''
| {{morse|dash|dot|dot|dot|dash}}
| Start new section<ref name=ITU_MC_Rec/> / paragraph<ref name=ARRL_Oper_Man/><ref name=ARRL_Send_CW/>
| Space down two lines; typewritten CR-LF-LF. Decoder software may show "'''='''".<ref name=ITU_MC_Rec/>
| {{small|''dah di di di dah''}}
| '''=''', '''–{{hair space}}–''' <ref name=ITU_MC_Rec/>
|-
| '''{{overline|CT}}'''
| {{morse|dash|dot|dash|dot|dash}}
| Start of<br/>transmission<ref name=ITU_MC_Rec/><br/>Start of new<br/>message<ref name=ARRL_Oper_Man/><ref name=ARRL_Send_CW/>
| Attention<ref name=ARRL_Oper_Man/><ref name=ARRL_Send_CW/> commencing transmission. Also written {{overline|'''{{sc|KA}}'''}}.
| {{small|''dah di dah di dah''}}
| 
|-
| '''{{overline|HH}}''' ...
| {{morse|dot|dot|dot|dot|dot|dot|dot|dot}}
| Error /<br/>correction<ref name=ITU_MC_Rec/><ref name=ARRL_Oper_Man/>
| Always followed by correct text.<ref name=ARRL_Oper_Man/> Equivalent to both {{overline|'''{{sc|IIII}}'''}} and {{overline|'''{{sc|EEEEEEEE}}'''}}&nbsp;. Sometimes transcribed as "???".
|colspan=2| {{nowrap|{{small|''di di di di di di di dit''}} }}
|- 
| '''K'''
| {{morse|dash|dot|dash}}
| Invitation for any station to transmit<ref name=ITU_MC_Rec/><ref name=ARRL_Oper_Man/><ref name=ARRL_Send_CW/>
| Lone alphabetic character "'''{{sc|K}}'''" at the end of a transmission.<ref name=ARRL_Oper_Man/>
| {{small|''dah di dah''}}
| '''{{sc|K}}'''<ref name=ITU_MC_Rec/>
|-
| '''X'''
| {{morse|dash|dot|dot|dash}}
| Full stop<ref name=ARRL_Oper_Man/>
| Lone alphabetic character "'''{{sc|X}}'''" surrounded by word spaces.<ref name=ARRL_Oper_Man/><ref name=ARRL_Send_CW/><br/>Substitute for period {{overline|'''{{sc|AAA}}'''}} in ARRL batched messages.
| {{small|''dah di di dah''}}
| '''{{sc|X}}'''<ref name=ITU_MC_Rec/>
|-
| '''?'''
| {{morse|dot|dot|dash|dash|dot|dot}}
| Please say<br/>again<ref name=ITU_MC_Rec/><ref name=ARRL_Oper_Man/><ref name=ARRL_Send_CW/>
| Lone question mark "'''?'''" from the receiving station in response to a transmission; possibly followed by {{nobr|'''{{sc|AA}}''' ...}} or {{nobr|'''{{sc|AB}}''' ... .}}<ref name=ARRL_Oper_Man/>
| {{small|''di di dah dah di dit''}}
| '''?'''<ref name=ITU_MC_Rec/><ref name=ARRL_Oper_Man/>
|-
| '''{{overline|KN}}'''
| {{morse|dash|dot|dash|dash|dot}}
| Invitation for<br/>named station<br/>to transmit<ref name=ARRL_Oper_Man/>
| Go ahead, specific named station.<ref name=ARRL_Oper_Man/> Decoder software may show equivalent character "'''('''".<ref name=ITU_MC_Rec/>
| {{small|''dah di dah dah dit''}}
| '''('''&nbsp;<ref name=ITU_MC_Rec/>
|-
| '''{{overline|NJ}}'''
| {{morse|dash|dot|dot|dash|dash|dash}}
| Shift to [[Wabun code]]
| Shift from [[Morse code]] to [[Wabun code]] [[Kana]] characters. Also written {{overline|'''{{sc|XM}}'''}}.
|colspan=2| {{small|''dah di di dah dah dah''}}
|-
| '''{{overline|SK}}'''
| {{morse|dot|dot|dot|dash|dot|dash}}
| {{nobr|End of work}}<ref name=ITU_MC_Rec/> /<br/>{{nobr|End of contact}}<ref name=ARRL_Oper_Man/><ref name=ARRL_Send_CW/><br/>/ Frequency {{nobr|no longer}} in use
| Also written {{overline|'''{{sc|VA}}'''}}.
| {{small|''di di di dah di dah''}}
| 
|-
| '''{{overline|SN}}'''
| {{morse|dot|dot|dot|dash|dot}}
| Understood<ref name=ARRL_Oper_Man/> / verify / verified<ref name=ITU_MC_Rec/>
| Message received and checks okay. Alternatively shift from [[Wabun code|Wabun]] to Morse code. "{{overline|'''{{sc|SN}}'''}}'''?'''" verification requested. Also written {{overline|'''{{sc|VE}}'''}}.
| {{small|''di di di dah dit''}}
| '''{{sc|Š}}''', '''{{sc|Ś}}'''{{efn|name=non-Latin}}
|-
| '''{{overline |[[SOS]]}}'''
| {{morse|dot|dot|dot|dash|dash|dash|dot|dot|dot}}
| Start of a distress signal<ref name=ITU_MC_Rec/><ref name=ARRL_Oper_Man/>
| Only used by the original distressed station, and only for imminent danger to life or property.<ref name=ITU_MC_Rec/> ({{Audio|SOS morse code.ogg|listen}})
|colspan=2| {{nowrap|{{small|''di di di dah dah dah di di dit''}} }}
|-
| '''{{overline|DDD}}'''
| {{morse|dash|dot|dot|dash|dot|dot|dash|dot|dot}}
| Start of a<br/>distress signal relayed from another station
| Used to forward a copy of a received "{{overline|'''{{sc|[[SOS]]}}'''}}". 
|colspan=2| {{nowrap|{{small|''dah di di dah di di dah di dit''}} }}
|-
| '''BK'''
| {{morse|dash|dot|dot|dot}}{{morse|dash|dot|dash}}
| Break in<br/>conversation<ref name=ARRL_Oper_Man/>
| [[Morse code abbreviations|Morse abbreviation]] for "back-to you" ([[Morse code abbreviations|Morse abbr.]]).<ref name=ARRL_Oper_Man/> In conversational Morse some use any of {{overline|'''{{sc|AR}}'''}}, {{overline|'''{{sc|BT}}'''}}, {{overline|'''{{sc|KN}}'''}}, or "'''{{sc|K}}'''" instead.
| {{small|{{nobr|''dah di di dit''}}   {{nobr|''dah di dah''}} }}
| '''{{sc|BK}}'''
|-
| '''CL'''
| {{morse|dash|dot|dash|dot}}{{morse|dot|dash|dot|dot}}
| Closing down<ref name=ARRL_Oper_Man/><ref name=ARRL_Send_CW/>
| Abbreviation for "closing station" ([[Morse code abbreviations|Morse abbr.]]).
| {{small|{{nobr|''dah di dah dit''}}   {{nobr|''di dah di dit''}} }}
| '''{{sc|CL}}'''
|}

==Obsolete prosigns==
{| class="wikitable"
|+ Historical Morse code prosigns
|-
! Prosign
! Matching voice procedure word
! Former code symbol
! Explanation
! Reference
|-
| {{sc|'''[[CQD]]'''}}
| Distress call
| {{morse|dash|dot|dash|dot}} {{morse|dash|dash|dot|dash}} {{morse|dash|dot|dot}}
| Obsolete code used to call all stations during distress (see '''{{sc|CQ}}'''). Replaced by [[SOS|'''{{overline|{{sc|SOS}}}}''' in 1906]] (see above).
|-
| {{sc|'''{{overline|VE}}'''}}
| General call
| {{morse|dot|dot|dot|dash|dot}}
| Code re-used for "Message verified" or "Message understood" (see '''{{overline|{{sc|SN}}}}''' above).<ref name=ITU_MC_Rec/> Replaced by '''{{sc|CQ}}''' (see above).<ref name=ITU_MC_Rec/>
|rowspan="6"| 1937 Royal Navy Signal Card<ref name=R-N-1937-card-htm>
{{cite report
 |title=Signal Card
 |date=1937
 |type=military reference
 |place=UK
 |publisher=Royal Navy
 |url=http://www.forposterityssake.ca/RCN-DOCS/SIGNAL_CARD_1937.htm
}}
</ref><ref name=R-N-1937-card-jpg>
{{cite AV media
 |title=Signal Card
 |medium=image
 |date=1937
 |place=UK
 |publisher=Royal Navy
 |url=https://hatchfive.files.wordpress.com/2014/12/e676af9a-0708-4c10-bbe1-fce8667ea652.jpg
}}
</ref>
|-
| {{sc|'''{{overline|NNNNN}}'''}}
| Answering sign
| {{morse|dash|dot|dash|dot|dash|dot|dash|dot|dash|dot}}
| Dropped.
|-
| {{math|{{nobr|{{sc|'''i'''}}{{spaces|1}}{{sc|'''i'''}} }} }}
| Separative sign break
| {{morse|dot|dot}} {{morse|dot|dot}}
| Generally replaced by '''{{overline|{{sc|BT}}}}''', although it is still used in [[Military Auxiliary Radio System|MARS]] CW operations,<ref name=Op-Guide-2009/> and other military standards.<ref name=ACP124/><br/>Later re-used for both a [[:wikt:ditto|"ditto"]] mark and to represent the warning "I&nbsp;repeat" before a duplicated transmission.
|-
| {{sc|'''{{overline|EEEEE}}'''}}
| Error
| {{morse|dot|dot|dot|dot|dot}}
| Exactly five dits (code for digit&nbsp;'''5'''<ref name=ITU_MC_Rec/>). Replaced by '''{{overline|{{sc|HH}}}}'''<ref name=ITU_MC_Rec/> (exactly eight dits, '''{{overline|{{sc|EEEEEEEE}}}}'''<ref name=ITU_MC_Rec/>).
|-
| {{sc|'''{{overline|RRRRR}}'''}}
| Receipt sign
| <span style="font-family: monospace; font-size: 40%; vertical-align: 1.5ex;"><span style="opacity: 0;">▄▄</span>▄<span style="opacity: 0;">▄</span>▄▄▄<span style="opacity: 0;">▄</span>▄<span style="opacity: 0;">▄</span>▄<span style="opacity: 0;">▄</span>▄▄▄<span style="opacity: 0;">▄</span>▄<span style="opacity: 0;">▄</span>▄<span style="opacity: 0;">▄</span>▄▄▄<span style="opacity: 0;">▄</span>▄<span style="opacity: 0;">▄</span>▄<span style="opacity: 0;">▄</span>▄▄▄<span style="opacity: 0;">▄</span>▄<span style="opacity: 0;">▄</span>▄<span style="opacity: 0;">▄</span>▄▄▄<span style="opacity: 0;">▄</span>▄<span style="opacity: 0;">▄</span></span> <!-- {{morse|dot|dash|dot|dot|dash|dot|dot|dash|dot|dot|dash|dot|dot|dash|dot}} stops after 10th element -->
| Replaced by '''{{sc|R}}'''.<ref name=ITU_MC_Rec/>
|-
| {{sc|'''É'''}} (printed as {{overline|e}})
| Further message sign
| {{morse|dot|dot|dash|dot|dot}}
| Re-purposed original ITU symbol for '''{{sc|É}}'''<ref name=ITU_MC_Rec/> not used in English. 
|}

==See also==
{{div col begin|colwidth=12em}}
* [[Morse code abbreviations]]
* [[Brevity code]]
* [[Procedure word]] (proword)
* [[Q code]]
* [[QSA and QRK code]]
* [[Z code]]
{{div col end}}

==Notes==
{{notelist}}

==References==
{{reflist|25em|refs=

<ref name=ACP124>
{{cite report
 |title=Communication Instructions Radio Telegraph Procedure
 |id=ACP&nbsp;124
 |type=military manual
 |url=http://www.navy-radio.com/manuals/acp/acp124d.pdf
 |via=Navy-Radio
}}
</ref>

<ref name=ACP131F>
<br/>
{{cite report
 |title=Communications Instructions Operating Signals
 |date=April 2009
 |id=ACP&nbsp;131(F)
 |publisher=[[NATO]] [[Combined Communications Electronics Board]]
 |type=military manual
 |url=http://jcs.dtic.mil/j6/cceb/acps/acp131/ACP131F09.pdf |url-status=dead <!-- presumed -->
 |via=jcs.dtic.mil
 |archive-url=https://web.archive.org/web/20130215140321/http://jcs.dtic.mil/j6/cceb/acps/acp131/ACP131F09.pdf
 |archive-date=2013-02-15
}}
: Also, see article [[ACP 131]].
</ref>

<ref name=ARRL_Oper_Man>
<br/>
{{cite book
 |title=ARRL Operating Manual
 |edition=10th
 |date=8 October 2012
 |type=textbook
 |place=Newington, CT
 |publisher=[[American Radio Relay League]]
 |isbn=978-0872595965
}}
</ref>

<ref name=ARRL_Send_CW>
<br/>
{{cite book
 |section=Chapter&nbsp;3: Sending messages in CW
 |title=ARRL Network Reference Manual
 |date=25 September 2002
 |type=procedure manual
 |place=Newington, CT
 |publisher=[[American Radio Relay League]]
 |section-url=http://www.arrl.org/files/file/Public%20Service/MPG304A.pdf
}}
</ref>

<ref name=Benedktsn-Kjartnsn-2014-09-27>
{{cite conference
 |last1=Benediktsson |first1=Kristjan, (TF3KB)
 |last2=Kjartansson  |first2=Villi
 |collaboration=Iceland Radio Association
 |date=21–27 September 2014
 |title=Resolution on conflicting CW procedure
 |conference=International Amateur Radio Union Region&nbsp;1 2014 General Conference
 |place=Varna-Albena, Bulgaria
 |id=paper VA14 C3 40
 |url=http://www.ira.is/wp-content/uploads/2017/07/VA14_C3_40-IRA-Conflicting-CW-Procedure.pdf
}}
</ref>

<ref name="Deutsch-Österreich-Telegr-1851">
{{cite report
 |title=[No title cited]
 |publisher=Deutsch-Österreichischer Telegraphenverein (German-Austrian Telegraph Union)
 |year=1851
 |lang=DE
 |quote=The Deutsch-Österreichischer Telegraphenverein officially adopted Gerke's redaction / revision of Morse code in 1851.
}}{{full citation needed|date=May 2021}} <!-- Same problem needs help in [[Morse code]] ref § -->
</ref>

<ref name=FM24-6>
{{cite book
 |title=Radio Operator's Manual
 |year=1945
 |id=FM24-6
 |series=United States War Department
 |type=military field manual
 |publisher=Army Field Printing Plant, CAS
 |place=Fort Monroe, VA
 |url=https://archive.org/details/Fm24-6
}}
</ref>

<ref name=ICS-102>
<br/>
{{cite report
 |title=International Code of Signals
 |orig-date=1855, 1969  |year=2003  |edition=United States
 |id=pub&nbsp;102
 |series=Maritime Safety Information Division
 |place=Bethesda, MD
 |publisher=National Imagery and Mapping Agency
 |url=http://www.seasources.net/PDF/PUB102.pdf
 |via=SeaSources.net
}}
</ref>

<ref name=ITU_MC_Rec>
<br/>
{{cite report
 |title=International Morse Code
 |date=October 2009
 |series=ITU Recommendation
 |id=ITU-R M.1677-1
 |type=international standard
 |place=Geneva, CH
 |publisher=[[International Telecommunication Union]]
 |department=[[ITU-R|Radiocommunication Sector]]
 |url=https://www.itu.int/rec/R-REC-M.1677/en  |lang=en
}}
</ref>

<ref name=ITU-R-M-1170>
{{cite report
 |title=Morse Telegraphy Procedures in the Maritime Mobile Service
 |date=March 2012
 |department=[[ITU-R|Radiocommunication Sector]]
 |series=ITU Recommendation
 |id=ITU-R M.1170-1
 |type=international standard
 |place=Geneva, CH
 |publisher=[[International Telecommunication Union]]
 |url=https://www.itu.int/dms_pubrec/itu-r/rec/m/R-REC-M.1170-1-201203-I!!PDF-E.pdf   |lang=en
 |via=ITU.int
}}
</ref>

<ref name=ITU-R-M-1172>
<br/>
{{cite report
 |title=Miscellaneous Abbreviations and Signals to be used for Radiocommunications in the Maritime Mobile Service
 |department=[[ITU-R|Radiocommunication Sector]]
 |series=ITU Recommendation
 |id=ITU-R M.1172
 |type=international standard
 |location=Geneva, CH
 |publisher=[[International Telecommunication Union]]
 |url=https://www.itu.int/rec/R-REC-M.1172/en  |lang=en
 |via=ITU.int
}}
</ref>

<ref name=Op-Guide-2009>
{{cite report
 |editor1-first=David  |editor1-last=Knight
 |editor2-first=Jerry  |editor2-last=Ryan
 |title=Radiotelegraph Operations Guide
 |date=May 2009
 |series=[[Military Auxiliary Radio System|MARS]] Training Manual
 |publisher=[[United States Air Force]]
 |type=military procedure manual
 |url=http://www.qsl.net/aga6la/Radiotelegraph%20Operations%20Guide%20May%202009.pdf
 |via=QSL.net
}}
</ref>

<!--
<ref name=R-N-1937-card-htm>
{{cite report
 |title=Signal Card
 |date=1937
 |type=military reference
 |place=UK
 |publisher=Royal Navy
 |url=http://www.forposterityssake.ca/RCN-DOCS/SIGNAL_CARD_1937.htm
}}
</ref>

<ref name=R-N-1937-card-jpg>
{{cite AV media
 |title=Signal Card
 |medium=image
 |date=1937
 |place=UK
 |publisher=Royal Navy
 |url=https://hatchfive.files.wordpress.com/2014/12/e676af9a-0708-4c10-bbe1-fce8667ea652.jpg
}}
</ref>
-->

<ref name=Smithsonian-Report-1879>
{{cite report
 |title=Annual Report of the Board of Regents of the Smithsonian Institution for the Year 1878
 |year=1879
 |pages=358–360
 |place=Washington, DC
 |publisher=Smithsonian Institution
 |via=Archive.org
 |url=https://archive.org/details/annualreportofbo1878smit/page/358/mode/2up
 |access-date=2021-03-17
}}
</ref>

}} <!-- end of "refs=" -->

{{Morse code}}

{{DEFAULTSORT:Prosigns for Morse Code}}
[[Category:Morse code]]
[[Category:Operating signals]]