Pronounciation of Letters and Numerals

To avoid confusion and errors during voice transmission, special

techniques have been developed for pronouncing letters and numerals.
These special techniques resulted in the phonetic alphabet and phonetic
numerals.

The phonetic alphabet is used by the operator to spell difficult words and
thereby prevent misunderstanding on the part of the receiving operator.
The words of the phonetic alphabet, which is a word alphabet and not a
code, are pronounced in the tables below.

The phonetic alphabet is also used for the transmission of encrypted

messages. For example, the cipher group CMVVX is spoken "CHARLIE
MIKE VICTOR VICTOR XRAY."

A Alpha N November
B Bravo O Oscar
C Charlie P Papa
D Delta Q Quebec
E Echo R Romeo
F Foxtrot S Sierra
G Golf T Tango
H Hotel U Uniform
I India V Victor
J Juliet W Whiskey
K Kilo X X-ray
L Lima Y Yankee
M Mike Z Zulu

Numbers are spoken digit by digit, except that exact multiples of thousands
may be spoken as such. For example, 84 is "AIT FOW ER", 2,500 is "TOO
FIFE ZE RO ZE RO," and 16,000 is "WUN SIX TOUSAND."
The date-time group is always spoken digit by digit, followed by the time
zone indication. For example, 291205Z is "TOO NIN-ER WUN TOO ZE-RO
FIFE ZOO-LOO."
Map coordinates and call sign suffixes also are spoken digit by digit, but
these were often disguised by numbers (See Shackles).
Procedure Words

To keep voice transmission as short and clear as possible, RTO's used

procedure (Pro-words)words to take the place of long sentences. The table
below contains all the Pro-words you will need.

ALL AFTER I refer to the portion of the message that follows.....

ALL BEFORE I refer to the portion of the message that precedes

AUTHENTICATE A demand for a code word to make sure that the

transmission is not by an enemy imposter

I AUTHENTICATE This is the reply at a challenge to Authenticate.

BREAK Announces the end or part of the message

CORRECT Confirms that a repetition matches the message sent out

CORRECTION Announces that a previous message is to be sent out with

the corrections added

DISREGARD THIS TRANSMISSION This transmission is in error,

disregard it.

DO NOT ANSWER Stations are called not to answer this call. This word is
always ends with OUT

EXECUTE Carry out the purpose of the message

EXEMPT The addressee destinations immediately following are exempted

from the collective call

FIGURES Numerals or numbers to follow

FLASH Announces the beginning of an emergency message

FROM Announces the source of the message

GREEN Conditions are safe

GROUPS The message contains the number of groups indicated by the

numerical following

HOTEL ALPHA "Haul Ass!" Go somewhere quickly

HOTEL ECHO "High Explosives" This warns of immediate incoming
explosive rounds or a request for the same

I READ BACK The following is my response to your instructions to Read

Back.

I SAY AGAIN Announces the repetition of a message

I SPELL Announces that the next message will be spelled out letter by
letter

I VERIFY That which follows has been varified at your request, and is
repeated.

IMMEDIATE Announces the beginning of a priority message

MESSAGE A message which requires recording is about to follow

MORE TO FOLLOW There is more of the message to follow.

NUMBER Station serial number

OUT Announces the end of communications

OVER Used at the end of every section of a message

PRIORITY Announcing a prority message.

RADIO CHECK Checking to see if there is still a connection

READ BACK Read the message you just received back to confirm it is
correct

RED Situation is dangerous

ROGER Used to acknowledge that a message has been received

ROUTINE Announces a non-priority message

SAY AGAIN A request that the last message be repeated

SILENCE Tells all RTO's to stop transmitting. Often if eavesdropping is

suspected or radio transmittions are giving away positions

SILENCE LIFTED Tells RTO's that transmittions can start again

SIX Commander

SPEAK SLOWER Your message to to fast to understand, speak slower.

THAT IS CORRECT You are correct or what you have transmitted is

correct

THIS IS This transmission is from [CALLSIGN or ID]

TIME That which immediately follows is the time or date-time group of the
message

UNKNOWN STATION The identity of the station of which I am

communicating with is unknown

VARIFY Varify the message or portion of message that is indicated

WAIT Announces a pause for a few seconds

WAIT OUT I must pause for longer than a few seconds

WILCO I have received your signal, understand it and will comply. Similar
to ROGER

WRONG Your last transmission was wrong.

Standard Alpha code 3 Letter Groups

In Vietnam standard Alpha code three letter groups were used. These were
similar to Pro-words, accept they were in basic code. Each three letter
groups could mean a word or sentence. These codes are kept by the RTO
or Platoon Leader in the Signal Operating Instructions (SOI) and this could
be changed daily. For re-enactment purposes you could keep it the same.
A standard Alpha code could be ROMEO PAPA ALPHA. This may translate
to "Rally with us at Base Camp".

Brevity and Security Codes

Two types of codes are normally used in tactical communications: Security

Codes and Brevity Codes. A code used to hide meanings from another
party is a security code (These included 3 letter Groups and Shackles). A
code used to shorten transmissions is a brevity code. For example LZ is a
brevity code for Landing zone. A brevity code only shortens transmission; it
does not provide security. Lists of these codes are referred to as a brevity
list.
Shackles

In Vietnam they used something called SHACKLES. These were 10 letter

code words for 0 through to 9 to translate to map co-ordinates. So the
numbers 0-9 were represented by letters and those letters were read out as
radio alphabet and always as a 10 letter word. This is similar to I SPEll but
with a a basic form of security code.

Thus the co-ordinates 31630 21600 could be the letters

E,C,L,E,W,S,C,L,W,W. This would be read out as:

ECHO, CHARLIE, LIMA, EHCO, WHISKEY, SIERRA, CHARLIE,

WHISKEY, WHISKEY.

Signal Operating Instructions (SOI)

The Platoon Leader or the RTO would carry the Signal Operating
Instructions (SOI) which contained the frequencies and call signs of all units
in the area and day codes. This enables you to send and receive coded
messages. The SOI provides the organisation of stations into nets, assigns
call signs, designates net control stations (NCS), and assigns frequencies.
It also provides information on changes to alternate frequencies and on
authentication. In addition, the security procedures that must be used by
radio operators in the command are included in the SOI supplemental
instructions.

Signal Operating Instructions (SOI)

The company commander or the RTO would carry the Signal Operating
Instructions (SOI) which contained the frequencies and call signs of all units
in the area and day codes. This enables you to send and receive coded
messages. The SOI provides the organisation of stations into nets, assigns
call signs, designates net control stations (NCS), and assigns frequencies.
It also provides information on changes to alternate frequencies and on
authentication. In addition, the security procedures that must be used by
radio operators in the command are included in the SOI supplemental
instructions.

If you are an RTO then it would be advisable to create a pocket sized SOI
for yourself. Decide which callsigns and frequencies you will use and the
authentication send and reply codes. Make sure this book doesn't fall into
enemy hands!
Tatical Callsigns

Call signs are used in radio communications to identify a communications

facility, a command, an authority, or a unit. There are two forms of call
signs: Complete Call Signs and Abbreviated Call Signs.

Complete call signs usually consist of a letter - number - letter combination

and a suffix, or a name and/or number. These are used when entering a
net in which you do not normally operate.

Abbreviated call signs are used at all other times. Platoon call signs were
always two digit consecutive numbers such as 41, 42, 43, 44. Call signs
also consisted of pronouncable words Red Fox, but they tended to get
warped into weird and colourful names like Robin Hood and Boo Peep.

EXAMPLES:

Complete Call Sign: A2 7-6-5-0

Abbreviated Call Sign: 7-6-5-0

If no confusion exists as to which operators are on the radio net, no call

signs need be used.

Radio ID

Each and every Battalion, Company, Platoon, and Squad had a radio ID.
Radio ID's are based on the tables below.

ALPHA BRAVO CHARLIE DELTA

Company A Company B Company C Company D

HOTEL LIMA MIKE NOVEMBER OSCAR ECHO

Headquarters First Second Third Fourth Recon
Platoon Platoon Platoon Platoon Platoon Platoon

Take the 2-7 Air Cavalry Re-enactment group. They are, 2nd Battalion,
Alpha Company, 1st Platoon and operate 1st and 2nd Squads.

Their Radio ID's are 2 (2nd Battalion) ALPHA (Company A) LIMA (1st
Platoon) 1 (1st Sqaud).

Thus their Radio ID is shortened to:

2 ALPHA LIMA 1 or 2 ALPHA LIMA 2

Platoon & Squad Leaders Id

6 5 4 3 2 1
Commanding Next in Weapons 3th Squad 2 Squad 1st Squad
nd

Officer Command Squad Leader Leader Leader

Leader

When Platoons and Squad Leaders send each other messages, sometimes
they are identified as a number. Thus if you heard "THIS IS RED FOX 6,
OVER" you would be hearing Red Fox's commanding officer. The
Commanding Officer or Senior Officer of a Unit is always a "6". Next in
command is always a "5". Weapons squad leader is a "4". Third squad
leader is a "3". Second squad leader is a "2". First squad leader is a "1".

Authentication

Combat experience in Vietnam proved that false radio communications by

the enemy contributed to substantial numbers of casualties and caused
many missions to fall short of desired results. Proper authentication
procedures can prevent an enemy from posing as a friendly station. The
enemy is adept at radio communications and needs only a moderate
degree of skill to seriously affect communication when we do not
authenticate. A balance has to be struck so that effective communications
is maintained without harassment of friendly communications.
Authentication is one of the best means available to stop enemy infiltration
efforts.

Operators are required to authenticate when they:

· Suspect a transmission is from an enemy station operating in the net

(deception).
· Direct a station to go to radio silence or to break that silence.
· Are challenged to authenticate.
· Talk about enemy contact
· Give an early warning report, or issue any follow-up report.
· Transmit directions, which affect the tactical situation such as "Move
to..." or "Turn off the radio."
· Cancel a message.
· Open the net or resume transmitting after a long period of silence.
· Transmit to someone who is under radio listening silence.
· Transmit a classified message in the clear.
· Transmit messages in the blind; that is, neither desiring nor
expecting a reply.
Challenge if you are not sure that authentication is required. If a station
takes more than 5 seconds to authenticate, rechallenge. Why 5 seconds?
Because an enemy operator may try to contact another station and have it
respond to that same challenge, thereby obtaining the appropriate reply to
your challenge.

This might be followed by a radio authenticator if you were entering a radio

network for the first time. This involves a challenge and a password. This is
to make sure the transmission is not an enemy imposter. A typical
response could be:

RTO 1: This is BULLDOG 6. 2 ALPHA LIMA 1, OVER"

RTO 2: "ROGER BULLDOG 6, AUTHENTICATE HOTEL LIMA, OVER"
RTO 1: "I AUTHENTICATE ALPHA, OVER"
RTO 2: "ROGER BULLDOG 6 THAT IS CORRECT"

RTO 2 has worked out the code from a simple authentication table like the
one below. The letters A to Z, printed in the sequence on the left hand side
of the table are the Row Designators. The numbers 0 to 9 also represent
those letters. So that if either the two test elements are a number then the
adjacent letter is used. E.g. if 4 is is part of the challenge, then E is used.

Assume that the RTO is challenged with the two test elements HL. The
correct method of authentication is to use the first letter to the right of the
last test element. To do this:

1 - First locate the first test element, "H" in the colomn of Row Designators.
2 - Scan across the row designated by "H" to find the second test element
"L"
3 - The first letter to the right of "L" is A. Therfore the challenged RTO
would respond "ALPHA".

If the second test element happens to be the last letter in the row, then use
the first letter in the same row as the authenticator e.g. as if HO were used
then the authenticator would be U.

When challenging, try not use the same pair of test elements. Remember
the enemy is alwasy listening.

Note: Transmission authentication is used only when it is impossible or

impractical to use challenge-reply authentication. For example:

• HELLCAT THIS IS FOXHOUND 3 DO NOT ANSWER

• TURN EAST AT CROSSROAD X-RAY
 • AUTHENTICATION IS VICTOR PAPA
• I SAY AGAIN
• HELLCAT THIS IS FOXHOUND 3 DO NOT ANSWER
• TURN EAST AT CROSSROAD X-RAY
• AUTHENTICATION IS VICTOR PAPA
• OUT

Slang Words and Phrases

When you hear radio communications there's a lot of slang words being
used, some of which won't be familiar to non-Americans. Here is some
slang words and phrases that I've picked up that may come in useful when
you are on your radios. For further Jargon refer to Abbreviations and
Terminology.

6 O'Clock: Points of view e.g. "WE GOT MOVEMENT AT 6 O'CLOCK"

ILLUM: Pronounced A-LUME A Illumination flare e.g. "IM FIRING A LUME,
OVER"
ADJUSTMENT:E.g. "CAN YOU PUT AN ADJUSTMENT ON THAT" or
"ADJUST YOUR FIRE, OVER"
AFFIRMATIVE:Yes
ASAP:Pronounced A-SAP
BREAKING STATION:Moving somewhere else.
CHARLIE:VC and NVA are referred to as Gooks and Charlie
CHECK FIRE: A signal for artillery to immediately halt firing
CLEAR TO FIRE
CONTACT: Contact with the enemy e.g. "WE GOT CONTACT ON THE
TREELINE"
ELIMINATION: E.g. "REQUEST ONE ROUND ELIMINATION"
ET TIME: Similar to ETA
FIREBIRD: An aircraft
FIRESHIP: Probably refers to a Huey or Gunship
GOTTA:Use words like GOTTA, GONA, NEEDIN' ...refuel
NEGATIVE:No
NINER:Number 9's are pronounced Nine'er
PARTY: E.g. "GET READY TO MOVE YOU'RE PARTY TO THE EAST"
MOVEMENT: When describing the enemy changing position E.g. "WE
GOT MOVEMENT"
STAND BY: A pause in the message but not like BREAK
SHOT OUT ON THE RUN: Fire hedging on the move
TREELINE: Describes the next bunch of trees e.g. "WE GOT MOVEMENT
IN THE TREELINE"
BUNKERLINE: Describes the outer line of bunkers e.g. "WE GOT
MOVEMENT ON THE BUNKERLINE"
WE GOT GOOKS IN THE WIRE: Meaning there are VC in the perimeter
WIRE: The wire is the perimeter, usually fenced of with barbed wire
Examples

Example 1

RTO 1: "GREYWOLF THIS IS BULLDOG 6. WHAT IS YOUR STATUS,

OVER"

RTO 2: "BULLDOG 6 THIS IS GREYWOLF 3. STATUS GREEN. STAND

BY FOR A SHACKLE. I SHACKLE ECHO, CHARLIE, LIMA, ECHO,
WHISKEY, SIERRA, CHARLIE, WHISKEY, WHISKEY BREAK. NO
CHARLIE FOUND, OVER"

RTO 1: AHHH ROGER GREY WOLF, OUT.

RTO 1 Who we now know is the Commanding Officer has asked Grey Wolf
what his status is. Grey Wolf is a 3rd Squad Leader and responds saying
conditions are safe. He then gives his map co-ordinates. Bulldog
acknowledges this and ends this piece of communication.

Example 2

RTO 1: "FLASH! 7-6-5-0 THIS IS 2-4. WE ARE UNDER FIRE, CONDITION

RED REQUEST FIRE MISSION, SAY AGAIN CONDITION RED
REQUEST FIRE MISSION OVER"

RTO 2: "AHH ROGER 2-4 FIRE MISSION AT YOUR DISCRESSION,

OVER"

RTO 1: "AHH ROGER. YEH OK. BE ADVISED HOTEL ECHO ON YOUR

POSITION, OVER"

ETO 2: "ROGER 2-4. WE'LL HOTEL ALPHA, MUCH ABLIGED, OUT"

Here RTO 1 gives out an emergency message saying he is under fire and
condition is dangerous. He requests a bombing raid and repeats his
request. RTO 2 acknowleges this and says that a bombing raid is at his
discression. RTO 1 advises RTO 2 that there may be high explosives
coming down in his area.

Example 3

RTO 1: "SKYLARK THIS IS GREYWOLF 6. REQUEST FIRE MISSION,

OVER"

AIRCRAFT: "GREYWOLF 6 THIS IS SKYLARK CONFIRM POSTITION,

OVER"

RTO 1: "SKYLARK THIS IS GREYWOLF 6. STAND BY FOR A SHACKLE.

I SHACKLE PAPA, X-RAY, VICTOR, CHARLIE, TANGO, SIERRA,
TANGO, ROMEO, FOXTROT, BRAVO, OVER"

AIRCRAFT: "AHHH ROGER GREYWOLF. ETA TANGO, OVER"

RTO 1: "ROGER SKYLARK I AM POPPING SMOKE, OVER"

AIRCRAFT: "I IDENTIFY PURPLE, OVER"

RTO 1: "RAJAR SKYALRK, I POPPED PURPLE, OVER"

RTO 1 then talks to an aircraft to find the nearest sortie. Skylark asks him
to confirm RTO 1's position which he does by SHACKLE. RTO 1 then pops
a smoke not telling the Skylark the colour (For security reasons). The
aircraft reports what colour he sees and RTO confirms that that is the
colour.