1. COMMUNICATIONS FUNDAMENTALS
SEABEE COMBAT WARFARE NCR SPECIFIC
105 - COMMUNICATIONS FUNDAMENTALS
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2. COMMUNICATION FUNDAMENTALS
References:
[a] NAVEDTRA 14234, Seabee Combat Handbook, Vol. 1
[b] MCRP B, Radio Operator’s Handbook
[c] Harris Guide (Rev. A), AN/PRC-150(V)(C), Man Pack Radio (Operator’s Manual)
[d] Astro XTS 5000 User Guide
[e] TM , SINCGARS, AN/PRC-119 (Operator’s Manual)
[f] COMFIRSTNCDINST
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3. COMMUNICATION FUNDAMENTALS
105.1 Explain the importance of messenger service. [ref. a, ch. 11]
Messenger service is accomplished by personal courier or by wire. Personal courier is the most secure and can evade enemy probing but is slowest.
Wire is secure as it does not broadcast over the air and is faster than personal courier but routes are fixed and can be probed by enemy and exploited.
Radio is the most flexible but can be detected by enemy and requires equipment.
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4. COMMUNICATION FUNDAMENTALS
Discuss the BEADWINDOW codes. [ref. a, ch. 11]
BEADWINDOW: A real-time procedure used to alert circuit operators that an unauthorized disclosure has occurred over a non secured circuit. The BEADWINDOW procedure uses the key number from the EEFI list to identify the information disclosed. Key numbers are used with BEADWINDOW transmissions

5. COMMUNICATION FUNDAMENTALS
COMMON BEADWINDOW CODES 01
POSITION
Friendly or enemy position, movement or intended movement: position, course, speed, altitude, or destination of ‘any air, sea, or ground element unit or force. 02
CAPABILITIES
Friendly or enemy capabilities or limitations: force composition or identity, capabilities, limitations or significant casualties to special equipment, weapon systems, sensors, units, or personnel. Percentages of fuel or ammunition remaining. 03
OPERATIONS
Friendly or enemy operations, intentions, progress or results: operational or logistic intentions, assault objectives, mission participants, flying programs, mission situation reports, results of friendly or enemy operations. 04
ELECTRONIC
WARFARE
Friendly or enemy electronic warfare emission control (EW/EMCON) intentions, progress, or results: intention to employ electronic countermeasures (ECM), results of friendly or enemy electronic counter-countermeasures (ECCM), results of electronic warfare support measures (ESM), present or intended EMCON policy, and equipment affected by EMCON policy. 05
PERSONNEL
Friendly or enemy key personnel: movement or identity of friendly or enemy flag officers, distinguished visitors, unit commanders, and movements of key maintenance personnel indicating equipment limitations. 06
COMSEC
Friendly or enemy communications security (COMSEC) locations: linkage of codes or code words with plain language, compromise of changing frequencies or linkage with line numbers, circuit designator linkage of changing call signs with previous call signs or units, compromise of encrypted or classified call signs, and incorrect authentication procedure. 07
WRONG
CIRCUIT
Inappropriate transmission: information requested, transmitted or about to be transmitted that should not be passed on the circuit because it either requires greater security protection or is not appropriate to the purpose for which the circuit is provided.

6. COMMUNICATION FUNDAMENTALS
105.3 Discuss the following precedence pro-words and their order of importance.
FLASH (Z) Message is delivered as fast as humanly possible to 10 minutes.
IMMEDIATE (O) Message is delivered within 30 minutes.
PRIORITY (P) Message is delivered within 3 hours.
ROUTINE (R) Message is delivered with 6 hours or the next business day.

7. COMMUNICATION FUNDAMENTALS
105.4 Discuss the seven components of a radio link.
a. Transmitter – unit that converts the intelligence to Radio Frequency (RF), amplifies the RF and sends to the transmitting antenna.
b. Power supply – unit converts AC/DC power into required voltages for Transmitter/Receiver units.

8. COMMUNICATION FUNDAMENTALS
c. Transmission Lines – Medium that transfers the RF from/to transmitter/receiver to antenna(s). Usually a coax cable.
d. Transmitting Antenna – unit that broadcasts the RF in a predetermined pattern for maximum efficiency. High powered antennas are usually identified with a RED base.
e. Propagation path – The path RF travels from the transmitting antenna to the receiving antenna.

9. COMMUNICATION FUNDAMENTALS
f. Receiving Antenna – Unit that receives RF. Antenna is designed to catch RF and increase the gain of weak signals. Receive antennas are marked with a blue base.
g. Receiver – unit that takes the RF in and converts it to intelligence.

10. COMMUNICATION FUNDAMENTALS
105.5 Discuss frequency range characteristics.
a. UHF (ULTRA HIGH FRQUENCY)
Range: 300Mhz to 3000Mhz (or 3Ghz) (mobile phones)
Line of sight (LOS) operation
Better with data handling than VHF.
More vulnerable to atmosphere and man made objects than VHF signals.

11. COMMUNICATION FUNDAMENTALS
105.5b. VHF (VERY HIGH FREQUENCY)
Range: 30Mhz to 300Mhz
Line of sight (LOS) operation
Better data handling than HF.
Less vulnerable to atmosphere than HF and man made/terrain objects than UHF signals.

12. COMMUNICATION FUNDAMENTALS
105.5c. HF (HIGH FREQUENCY)
Range: 3Mhz to 30Mhz
Over the Horizon (OTH)
Best medium/long range frequency for quick communication because of ionosphere reflection. Can go over most obstacles because of sky wave. But different frequencies are reflected during the day/night times and solar activity.

13. COMMUNICATION FUNDAMENTALS
105.6 Discuss Single Channel Radio (SCR) radio equipment, the principal means of communications support for MAGTF operations on the move.
SINCGARS (SINgle Channel Ground/Airborne Radio System) family. The RT-1523E is the heart of the system. It employs a single frequency to communicate to the distant receiver. It is VHF (Line of Sight) FM with 2230 different frequencies to choose from. Has built in encryption card.

14. COMMUNICATION FUNDAMENTALS
105.7 Explain employment considerations and capabilities of High Frequency Radio.
HF operation is dependent on the best location of the antenna and wave propagation. There are three main types that NCF employs HF antennas:
a. Omni directional – RF energy is radiated in a 360 degree pattern. Best employed for transmitting to moving radios.

15. COMMUNICATION FUNDAMENTALS
105.7b. Bi - directional – RF energy is radiated in a narrow beam pattern. The distant end is at a fixed bearing and requires less energy to reach.
105.7c. Near Vertical Inductance Skywave - (NVIS). Transmitting elements are nearly horizontal so the energy is radiated towards to ionosphere where it can reflected back to Earth. It then bounces back to the Ionosphere and the pattern repeats itself until the energy is dissipated. Used for hilly areas.

16. COMMUNICATION FUNDAMENTALS
105.8 Identify the primary combat VHF radios used in the MAGTF for communications for command and control and fire support on the battlefield.
SINCGARS (SINgle Channel Ground/Airborne Radio System) family. NCF currently employs the RT -1523E configured in three ways:

17. . COMMUNICATION FUNDAMENTALS
105.8a Identify the primary combat VHF radios used in the MAGTF for communications for command and control and fire support on the battlefield.
1. AN/PRC-119 – Portable man pack
2 lithium batteries (BA 5590)
1 Bag frame
1 RT-1523E
1 handset
1 3ft flexible tape antenna
1 10ft whip antenna

18. COMMUNICATION FUNDAMENTALS
Receiver- Transmitter (RT) 1523 (PRC-119)
General Characteristics
VHF SINGARS Radio
30 to MHz freq
2320 channels/freq’s
Sends and receives secure voice and digital data
6 COMSEC channels/ 6 frequency hopping channels
8 single channels (SC) for plain text
Transmits 200 meters to 10 kilometers or more
Batteries last 4 (BB690) to 30 (BA5590) hrs depending on type & use
Antenna Systems
3ft tape – up to 5 miles
10ft whip- up to 10 miles
OE-254- up to 36 miles
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19. COMMUNICATION FUNDAMENTALS
2. AN/VRC-90 – Vehicle /Base radio
1 lithium batteries (BA 5590)
1 RT-1523E
1 AM-7239 Amp/Radio Mount
1 AM w amplifier
1 handset
1 AS-3900 vehicle antenna (Range appox. 25NM)

20. COMMUNICATION FUNDAMENTALS
AN/VRC-90A
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21. COMMUNICATION FUNDAMENTALS
3. AN/VRC-92 – Vehicle Dual Radio (RETRANS SITE)
2 lithium batteries (BA 5590)
2 RT-1523E
2 handsets
1 AM 7239 Amp/Radio mount
2 AM 7238 Amplifiers
1 AM 6353 Amp mount
2 AS-3900 Vehicle Antennas (Range 25NM)
2 OE-254 Field Antennas (Range 35NM)

22. COMMUNICATION FUNDAMENTALS
AN/VRC-92A For RETRANS SITE
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23. COMMUNICATION FUNDAMENTALS
105.9 Discuss radio frequency interferences and ways to prevent them.

24. COMMUNICATION FUNDAMENTALS
Discuss the capabilities of the NCR TOA communication assets.
a. XTS-5000
b. AN/PRC-119
c. AN/PRC-150

25. COMMUNICATION FUNDAMENTALS
XTS-5000 Portable Radio
Handheld secure radio
VHF radio with 1 – 6 watts
Crypto fill via cable
VHF – 136 to 174 MHZ
Range – 1 to 3 miles

26. COMMUNICATION FUNDAMENTALS
AN/PRC-150
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27. COMMUNICATION FUNDAMENTALS
Identify the following capabilities for “Radio” receiver-transmitter (RT 1694):
Long range secure radio (RT-1694 HF)
No external encryption device required
Requires 2 BA-5590 or 2 BB-690 Batteries
Smaller and lighter than AN/PRC-104
Frequency Range: MHz
Modes of Operation:
Lower Side Band (LSB), Upper Side Band (USB), Amplitude Modulation Equivalent (AME), Continuous Wave (CW) Modulation, Frequency Modulation (FM)
Power Output: (HF) 1, 5, 20 Watts PEP/avg. (FM) 1, 5, 10 Watts PEP/avg.
Pre-Set Channels: 200
Data Rate: 39 tone data to 2400 bps; Serial tone data to 2400 bps (TX), 75 bps (RX);
FSK data to 600 bps
Embedded US Type I Encryption: VINSON (Voice & Data) ANDVT/KYV-5 (Voice & Data)
KG-84C (Data)
Dimensions: in x 3.5 in x 13.2 in (485.1 inch3)
Weight: 10 lb. (without batteries)
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28. COMMUNICATION FUNDAMENTALS
Discuss the purpose of security clearance and access lists.
Security Clearance – A level of clearance is required in order to carry out specific duties. Security Clearances (Confidential, Secret, Top Secret) depending on the level requires a back ground check that is conducted by the NSA. The security clearance must be equal to or higher in order to access.
Access List – A list of personnel authorized by the CO for access to classified material.