GENERAL. the Commandos Use Both Technical and Non-Technical Methods of Communication

CHAPTER SEVEN

COMMUNICATIONS

GENERAL. The Commandos use both technical and non-technical methods of communication.

7-1. TECHNICAL COMMUNICATION.

a. AN/PRC 77. The AN/PRC-77 set covers the 30 to 75.95 MHZ band in 5 KHZ increments. It is a medium weight radio that is best utilized for squad or platoon operations. The following chapter outlines assembly, operation, and trouble-shooting for both radios.

1. Radio assembly

(a) Check and install the battery

(b) Inspect the battery box for dirt and damage

(c) Check battery condition

(d) Place battery in box

(e) Close battery cover and secure latches

2. Antenna

(a) Inspect antenna for damage

(b) Screw antenna into radio (screw into base first if using the whip antenna)

3. Handset

(a) Inspect the handset for damage

(b) Push handset onto audio connector and twist to lock into place

4. Operation and frequency setting

(a) Set frequency.

(b) Push handset button. Allow approx 1 second for battery to come to full power.

5. Troubleshooting

b. MOTOROLA TALK-ABOUT. The Motorola Talk-About radio is the primary tactical radio for the Command Squadron. Primary and alternate channels without codes will be randomly selected for each Commando operation. Brevity codes will be used to transmit channel changes during the operation.

c. Radio Procedures

(1) Prowords. Procedure words or prowords are words used to expedite message handling on circuits where radiotelephone procedure is employed. They are used in standard phrases between radio operators to shorten and minimize transmissions.

(a) "THIS IS" - This transmission is from the station whose designator immediately follows.

(b) "OVER" - This is the end of my transmission to you

and a response is necessary. Go ahead, transmit.

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

(d) "ROGER" - I have received your last transmission satisfactorily.

(e) "SAY AGAIN" - Repeat all of your last transmission. Followed by identification data means "Repeat ______portion indicated".

(f) "WAIT" - I must pause for a few seconds.

(g) "WAIT-OUT" - I must pause longer than a few seconds.

(h) "I SPELL" - I will spell this word phonetically.

(j) "CORRECT" - You are correct, or what you have transmitted is correct.

(k) "CORRECTION" - An error has been made in this transmission. Transmission will continue with the last word correctly transmitted.

(l) "DISREGARD THIS TRANSMISSION" - This transmission is in error. Disregard it. Used to cancel transmission while in progress and never used to cancel a transmission after a receipt has been received.

(m) "SAY AGAIN" - Repeat all of your last transmission. Followed by identification data, means "Repeat ______(portion indicated).

(n) "ALL AFTER" - The portion of the message to which I have referenced is all that which follows ______.

(o) "ALL BEFORE" - The portion of the message to which I have reference is all that which precedes ______.

(p) "WORD AFTER" - The word of the message to which I have reference is that which follows______.

(q) "WORD BEFORE" - The word of the message to which I have reference is that which precedes______.

(r) "I SAY AGAIN" - I am repeating transmission or portion indicated.

(s) "AUTHENTICATE" - The station called is to reply to the challenge that follows.

(t) "I AUTHENTICATE" - The group that follows is the reply to your challenge to authenticate.

(u) "AUTHENTICATION IS WRONG" - Check your authentication system.

(2) Call Signs. Calls signs are used to identify callers on a radio net. Units are NEVER identified in the clear.

7-2. NON-TECHNICAL COMMUNICATION.

a. HAND AND ARM SIGNALS. Commando’s must be proficient in communicating via hand and arm signals. Under many circumstances, use of verbal or technical means of communication may not be possible due to the situation and enemy proximity.

1. Bounding Overwatch: Places the2. Call Leaders Forward: Signals element

Squadron into a bounding overwatch and/or section CDRs forward to the SQDRN

movement. Usually followed with CDR.

signals to sections for overwatch

and maneuver.

3. Move Out: Initiates movement4. Increase Speed: Usually

or alerts unit to begin movement.means to double time or initiate assault.

5. Danger Area: A slashing motion across6. Map Check: A signal to inform

the throat. Usually followed by “Scrollthe unit of the reason for a stop

to the road” or security to indicate the

method of crossing.

7. Pace Count: A signal asking for8. Head Count: Signal is relayed to the

the current pace count (meters). back and the count is sent forward when in a file.

9. RTO: Signal for the RTO to come10. Rally: Used to direct the unit

forward.to indicate arrival at the ORP. If

followed by a pointing motion, it designates enroute rally points.

11. DISPERSE. Used to direct the unit12. Halt: Stop forward movement

to increase separation and seek

maximum cover and/or concealment such

as with the approach of enemy forces.

13. Freeze: Freeze in place and make14. ENEMY IN SITE: Alternate

no movement (usually indicates enemy signals include weapon upside down

presence).or a “pistol” made with the hand

pointed at the enemy upside down

15. ACTION (Right, Left, etc): Indicates 16. COLUMN: Column or file. (FM 21-60

the direction of attack.uses this signal for Travelling

movement formations)

17. ON LINE: On line formation 18. WEDGE: Wedge formation.

19. OUT OF ACTION: For a crew served20. DECREASE SPEED: Slow movement down.

weapon that is out of ammo or

inoperable.

21. COMMENCE FIRING: Start firing or 22. CEASE FIRING: Stop Shooting

engage targets.

23. SECURITY: Two fingers pointed towards24. TRAVELLING OVERWATCH. Signals

the eyes means move security team forward.squadron to open up and move in a

traveling overwatch formation

b. OTHER SIGNALS. Other types of communication may be effected by other means.

(1) Pyrotechnics.

(2) Whistles.

7-3. ENCRYPTION/DECRYPTION.

a. Authentication. There are two methods of authentication, challenge and reply and transmission authentication. The operational distinction between the two is that challenge and reply requires two-way communications, whereas transmission authentication does not. Each SOI will include an authenticator chart randomly created. A set letter combination is sent. The authentication letter is read directly below the second set letter. If the letter is at the bottom of the pad, the first letter in the top of the column is the authenticator. For example: Set letters DK would have an authenticator of J.

(1) When challenged for authentication, you select two letters at random (Except Z) to use for challenge.

(CALL SIGN) THIS IS (CALL SIGN) AUTHENTICATE KILO VICTOR OVER.

(2) To find the reply, go to the authentication tables KTC 1400( ). Use table "SET 01, PERIOD 01".

(3) Locate the first letter (K) in the LINE INDICATOR COLUMN at the left side of the table, follow the (K) row to the right until you find the next letter (V).

(4) The letter directly below (V) is the reply (S).

(CALL SIGN) I AUTHENTICATE SIERRA OVER.

b. Encryption.

(1) Trigraph Method.

(a) A trigraph can be easily constructed for low level encryption. The base/key letter is determined by the SOI.

(b) To use the trigraph to encrypt:

1. Located the unencrypted letter along the top row.

2. Follow the column down to the set letter. (For example: Unencrypted letter J, SET Letter F, Encrypted letter is P).

(c) To decrypt, find the SET letter in the first column. Find the encrypted letter in the key letter’s row. Read the unencrypted letter from the top row.

Tri-graph Chart (Key Letter B)

b. Tap Code. The tap code was developed for SERE situations to effect communications while in captivity. A series of taps is used to identify the letters of words to be spelled out. That tap code chart here is used only as a reference and should never be used except during training. Each letter is identified by a sequence of two sets of taps. The first sequence follows the first column “A F L Q V.” The second series identifies the letter in that row (i.e. two taps followed by three taps is the letter H). Entire conversations were conducted in the prison camps of Vietnam using this system. It is NOT a secure means of communication.

A B C D E

F G H I J

L M N O P

Q R S T U

V W X Y Z

Tap Code Chart

c. Pro-Word Numeric Encryption. A pro-word (one or two words) is designated to conduct an expedient encryption of numbers during an operation used primarily to report grid coordinates and frequencies. Each letter of the pro-word is assigned a number in sequence beginning from the number 1. For example, pro-word “SHARK LINED” would be used to send the the grid coordinate 482933 (RNHEAA). The transmission may include set letters for the pro-word and would sound like this: “F24 this is F25, I set Sierra Lima, I send Romeo November Hotel Echo Alpha Alpha Over.”

SHARK LINED

12345 67890

7-4. REPORT FORMATS. Transmissions are sent with only the line and number followed by the pertinent information (i.e. “Alpha Four Four, this is Delta Seven Six, Line One HALTS PAPA UNIFORM SIX THREE THREE SEVEN EIGHT ZERO”)

a. MEDEVAC Request. PROWORD MEDAC

(1) LZ Codename and location (6-digit UTM coordinates).

(2) Radio frequency and call sign (secure/nonsecure).

(3) Number of patients by precedence (URGENT, PRIORITY or ROUTINE).

(4) Special equipment required; e.g. hoist, penetrator, whole blood, etc.

(5) Number of patients by type (litter or ambulatory)

(6) Number and type of wound, injury, illness, etc.

(7) Method of marking pickup site (PZ)

(8) Patient nationality and status

(9) Terrain description (obstacles, slope, etc.).

b. Cache Report. PROWORD UNDER

(1) Purpose of cache (who intended for/functional purpose).

(2) Method of caching (concealment/burial/submersion).

(3) Contents (itemized list and how packaged). Use MARGE Bundle codes.

(4) Description of containers (number, size, weight).

(5) General area (country, province, town, village).

(6) Immediate area (initial reference point (IRP) and instructions (azimuth) to final reference point (FRP).

(7) Cache location (FRP and exact measurements (feet or meters)).

(8) Emplacement details (depth, type soil, physical covering, etc.).

(9) Operational data (equipment needed, routes to and from site, security forces, etc.).

(10) Date of emplacement/duration (how long contents will remain usable).

(11) Sketches/diagrams (aerial sketch with route from IRP to FRP).

c. Initial Entry Report. PROWORD ANGUS

(1) Mission Designator and SFODA codename.

(2) Location (6-digit UTM coordinates).

(3) Casualties. - Code name of personnel who are unable to continue the mission using code words listed below.

UNCLE - Killed in Action.

FROST - Wounded in Action (explain).

SPARK - Captured or Missing in Action.

(4) DTG contact/linkup made with friendly elements.

(5) Strength of FID/guerrilla force.

(6) Location of MSS/patrol base (6-digit UTM coordinates). If different from line 2.

(7) DTG surveillance established on target/area.

(8) Additional information.

d. Situation Report. PROWORD CYRIL

(1) Location of outstation(s) (6-digit UTM coordinates).

(2) Guerrilla/FID strength.

(3) Condition of detachment (excellent, good fair, poor).

(4) Enemy contact information (DTG, causality/status).

(5) Major activities since last report (what, where and when). Include post PSYOPS and TACAIR, etc. results in this paragraph. Also include non-nuclear destruction of targets.

(6) Projected major activities (what, where and when).

(7) Additional information.

e. Intelligence SPOT Report. PROWORD BORIS

(1) Size/type of unit (how many).

(2) Activity (what are they doing).

(3) Location (where are they).

(4) Uniform (who are they by unit identification, if unknown

what nationality).

(5) Time, DTG (if observed over a period of time state start and stop time).

(6) Equipment.

(7) Personalities (VIP's who can be identified).

(8) Source (if source is member of your unit - omit. If source

is by other means, i.e. indigenous personnel, so state. Follow-up with VALUE report).

(9) Evaluation (Enemy intent).

(10) Additional information.

f. Helicopter Landing Zone Survey Report. PROWORD HELIX

(1) Codename (operational element selects codename).

(2) Location (6-digit UTM coordinates).

(3) LZ size (in meters).

(4) DTG (time aircraft is required on station).

(5) Wind direction (cardinal direction wind is blowing from) and

velocity in knots.

(6) Recommended approach heading (magnetic).

(7) Open quadrant(s) (measure open quadrant from center of HLZ and report as a series of azimuths in magnetic degrees. The open quadrant indicates acceptable aircraft approaches).

(8) Soil composition.

(9) Obstacles (type, height in feet, azimuth and distance from center of HLZ).

(10) Authentication used by LZ security element (smoke, strobe, panel).

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