Radiotelephone Voice Procedure

Introduction to Radiotelephone Voice Procedure

ACP-125(G) NATO Allied Communications Publication

Voice Procedure

Voice procedure is necessary because:

a. Speech on a congested voice net in battle must be clear, concise and unambiguous. To avoid interference between speech and data, it will often be expedient to assign the passage of data traffic to logistic or admin nets rather than to those directly associated with command and control.

b. It must be assumed that all transmissions will be intercepted and analysed by potential adversaries, and used to provide radio location and signals intelligence. The use of a standard procedure is an important security measure against the constant threat of enemy electronic warfare activities.

c. Some form of discipline is needed to ensure that transmissions do not overlap, if two people send at one time the result is chaos.

Voice Procedure

The term Voice Procedure encompasses three related elements:

a. Protocol. The rules of use – how to start and finish a message. On mixed voice and data nets this includes the prowords used for the passage of data traffic.

b. Callsigns. Figures, letters, or combinations of both used to identify a communications station, an organization, or an individual on a radio net.

c. Secure Nets and Tactical Codes. The cryptographic systems employed to protect secure nets, and the tactical codes used to provide some degree of cryptographic protection for information transmitted over insecure nets.

Security of Information

Whether transmitted during training or on operations, all information of a long or short term nature likely to assist an enemy in wartime should be encoded, whenever possible, prior to its transmission on insecure radio.

Communications Security

Communications Security (COMSEC) is the collective title for the measures taken to protect all aspects of communications in order to deny information and intelligence to an enemy. This includes cryptographic security details of which are contained in national cryptographic instructions.

Radio Appointment Titles

A radio appointment title is a word used to identify the senior individual, by role or branch, at any given station. Radio appointment titles are unclassified and are not codewords; the security protection they provide is to conceal the rank and personal identity of the appointment, therefore concealing the organizational level of the net.

The use of radio appointment titles varies between services and nations; nonetheless, where participants are comfortable in their use, they are authorised for combined operating

Radio Appointment Titles

The most commonly used radio appointment title is SUNRAY which is used to identify the commander at any given station. Prowords used in conjunction are FETCH (title), used to request the relevant appointment to the handset, and (title) SPEAKING used by the requested appointment to report that they are at the handset.

Callsigns

A callsign is a combination of letters and figures that identify a communication facility, an organization, or an individual on a radio net. Its primary use is to establish and maintain communications. The callsign system to be used on an Allied net will be specified by the appropriate command HQ communications staff.

Callsigns

In a conversation between two stations, after the initial call and response, callsigns should be dropped altogether unless confusion is likely to arise by so doing. In different circumstances, some callsign systems allow users to abbreviate callsigns once communications have been established.

Callsigns

Full callsigns are to be used on the following occasions:

a. When first establishing a net.

b. When reporting into a previous established net.

c. In the transmission instructions and address components when a message is required to be relayed to a station on a different net.

Net Identification Callsign

A callsign allocated to each net which may be used by a station to provide the identity of their net when communicating to a station from a different net.

Speech Technique

Method of Speech. The key words to remember are Rhythm, Speed, Volume and Pitch (RSVP):

Rhythm.

Use short sentences divided into sensible phrases which maintain a natural rhythm; they should not be spoken word by word. Where pauses occur, the press-to-talk should be released to minimize transmission time and permit stations to break in when necessary

Speed.

Speak slightly slower than for normal conversation. Where a message is to be written down by the recipients, or in difficult conditions, extra time should be allowed to compensate for the receiving station experiencing the worst conditions. Speed of transmission is easily adjusted by increasing or decreasing the length of pauses between phrases, as opposed to altering the gaps between words; the latter will create an unnatural, halted style of speech, which is difficult to understand.

Volume.

The volume should be as for normal conversation. Shouting causes distortion and reverberation.

Pitch.

The voice should be pitched slightly higher than for normal conversation to improve clarity.

Pronunciation of Letters.

To help identify spoken letters of the alphabet a standard phonetic word alphabet is used. Each letter of the alphabet is represented by a uniquely pronounced word to enable consistent and accurate pronunciation. For example, BRAVO is the phonetic equivalent of the letter B and DELTA equates to the letter D.

A -Alpha

B- Bravo

C- Charlie

D- Delta

E - Echo

F- Foxtrot

G- Golf

H- Hotel

I- India

J- Juliett

K- Kilo

L- Lima

M- Mike

N- November

O- Oscar

P- Papa

Q- Quebec

R- Romeo

S- Sierra

T- Tango

U- Uniform

V- Victor

W- Whiskey

X- Xray

Y- Yankee

Z- Zulu

Pronunciation of Figures

Whenever figures are spoken in single digits over radio they are pronounced as shown in the next slide. The underlined portion of the spoken words indicates the syllables to be emphasized to make the figures distinctively audible.

Rules for Spelling

Spelling is necessary when difficult radio conditions prevent the reception of an obscure word, or of a word or group, which is unpronounceable. Such words or groups within the text of plain language messages may be spelt using the phonetic alphabet; they are preceded by the proword “I SPELL”. If the word is pronounceable and it is advantageous to do so, then it should be spoken before and after the spelling to help identify the word.

Rules for Spelling

Example A:

Pronounceable word – UNNA: …”UNNA- I spell, Uniform November November Alfa – UNNA”

Example B:

Unpronounceable word or group – UTFX: …”I spell, Uniform Tango Foxtrot X-ray”.

Rules for Spelling

Exceptions to this rule (precede phonetic spelling with the proword I SPELL), when letters are always spoken phonetically without the proword I SPELL are:

a. Callsigns and Net Identification Signs (NIS).

b. Grid references (UTMs).

c. Target indications

d. Authentication.

e. DTG zone suffix/SICs.

f. Address groups.

g. Encrypted text.

Rules for Numbers and Figures

When radio conditions are satisfactory and confusion will not arise, numbers in the text of a message may be spoken as in normal speech. During difficult conditions, or when extra care is necessary to avoid misunderstanding, numbers are sent figure by figure preceded by the proword FIGURES. This proword warns that figures follow immediately, to help distinguish them from other similarly pronounced words.

Rules for Numbers and Figures

Exceptions to this rule (the proword FIGURES precedes sending numbers figure by figure), when numbers are always spoken digit by digit without the proword FIGURES are:

a. Callsigns.

b. Grid references.

c. Target indications (except that exact multiples of a hundred or a thousand are pronounced as such).

d. Authentication.

e. Formal message date time groups (DTGs).

f. Within encrypted text groups.

Rules for Mixed Groups

The rules for sending mixed letter/figure groups incorporate the same principles that apply to sending letters and figures separately. The same information may be sent in two different ways depending on the circumstances.

Example A. Satisfactory conditions:

Mixed group spoken as

ACP 125 ACP one two five

Example B. Difficult conditions:

Mixed group spoken as

ACP 125 I SPELL Alfa Charlie Papa FIGURES one two five

Procedure words (prowords)

To keep voice transmissions as brief and clear as possible standard prowords are used in place of whole sentences. Prowords are easily pronounced and recognized words or phrases used to convey a specific predetermined meaning, for example.

ROGER - I have received your last transmission satisfactorily

OUT - This is the end of my transmission to you and no answer is required or expected.

Brevity codes

Messages transmitted in a set format, including data messages, may be shortened through the use of brevity codes. A brevity code is a list of numbers or letter, which equate to a standard predetermined vocabulary of words or phrases, for example equipment and commodity codes. Brevity codes can reduce long stereotyped sentences or lists to a few characters and save considerable time in transmission. It is however important to remember that such codes provide no security at all, and must be regarded as the equivalent of plain language when transmitted unencoded over radio.

LIST OF PROWORDS

ACKNOWLEDGE : Let me know that you have received and understood this

message.

AFFIRMATIVE : Yes, or permission granted.

BREAK To indicate the separation between portions of the message. (To

be used where there is no clear distinction between the text and

other portions of the message.)

CHANNEL : Change to channel .......... before proceeding.

CONFIRM : My version is _____. Is that correct?

CORRECTION An error has been made in this transmission (message indicated).

The correct version is _____.

LIST OF PROWORDS

GO AHEAD - Proceed with your message.

HOW DO YOU READ? - How well do you receive me?

I SAY AGAIN - Self-explanatory (use instead of “I repeat”).

MAYDAY - The spoken word for the distress signal.

MAYDAY RELAY - Is the spoken word for the distress relay signal.

NEGATIVE - No, or that is not correct, or I do not agree.

OVER - My transmission is ended and I expect a response from you.

OUT - Conversation is ended and no response is expected.

PAN PAN - The spoken word for the urgency signal.

LIST OF PROWORDS

PRUDONCE - During long distress situations, communications can resume on a restricted basis. Communication is to be restricted to ship's business or messages of a higher priority.

READBACK - Repeat all of this message back to me exactly as received after I have given OVER. (Do not use the word “repeat”.)

ROGER - I have received all of your last transmission.

ROGER NUMBER - I have received your message number ...

STANDBY - I must pause for a few seconds or minutes, please wait.

SAY AGAIN - Self-explanatory. (Do not use the word “repeat”.)

SÉCURITÉ - Is the spoken word for the safety signal.