B3

Question 1

ID the frequency range of the SINCGARS

Answer 1

SINCGARS operates with Frequency Modulation (FM) in the VHF spectrum from 30 MHz to 87.975 MHz

Question 2

ID the 4 requirements to operate a radio in frequency hopping mode

Answer 2

1. HOPSET
2. Transmission Security Key (TSK)
3. Time
4. Net ID

(Traffic Encryption Key (TEK) is also included in FH data, but not strictly required IOT operate in FH mode)

Question 3

Given a SINCGARS configuration, ID the power requirements

Answer 3

@PRC-119A:

• Main battery power. One of the following:
• BA-5590 (non-rechargeable lithium-ion)
• BB-390 (rechargeable nickel)
• BB-590 (rechargeable nickel-cadium)
• Hold-Up Battery (HUB)
• BA-5372 (non-rechargeable lithium-ion)
• Cannot power radio on its own

@PRC-119F: Identical PRC-119A

@All vehicle SINCGARS configs:

• 22-32 VDC
• Standard power available from batteries of all HMMWV variants
• Also require a HUB

Question 4

Given a SINCGARS vehicle configuration, identify the equipment nomenclature

Answer 4

VRC-87: 
One short range radio
VRC-88: 
One short range radio
Dismount capable
VRC-89:
One short range radio
One long range radio
VRC-90:
One long range radio
VRC-91:
One short range radio
One long range radio
VRC-92:
Two long range radios rtx cable???
MRC-145:
Two long range radios

Question 5

ID the principle mission of the AN/MRC-145

Answer 5

Retransmission of VHF nets

Question 6

ID the difference between AN/MRC-145 and AN/VRC-92

Answer 6

Both a vehicle and retransmission cable come SL-3 with MRC-145

Question 7

1. ID the power outputs of multi-band radios
2. ID the frequency ranges of multi-band radios
3. ID the operational modes of multi-band radios

Answer 7

PICTURE

Question 8

Given a radio configuration, associate the man-pack multi-band radio to its vehicle configuration

Answer 8

Man-pack- Vehicle Equivalent
PRC-117F-VRC-103
PRC-117G-VRC-114
PRC-152-VRC-110
PRC-148-VRC-111

Question 9

ID the 3 major components of a satellite

Answer 9

1. Transceiver
2. Antenna
3. Source of power generation

Question 10

ID the definition of a satellite’s footprint

Answer 10

• Area of communication coverage on the earth’s surface.
• It is the portion of the Earth that is effectively irradiated by that antenna and is determined by the type of orbit and the antenna’s directionality and size.
• It is the area with which a satellite can communicate.

Question 11

ID the type of orbit predominately used with communications satellites

Answer 11

Geostationary

Question 12

ID the 3 segments of a typical satellite communication system

Answer 12

• Space segment
• Ground segment
• Control segment

Question 13

ID the advantages of satellite communications

Answer 13

• Satellite links are unaffected by the propagation variations that interfere with HF radio
• Free from high attenuation of wire or cable facilities
• Capable of spanning long distances
• Higher bandwidth links with higher fidelity
• Not dependent upon reflection/refraction
• Only slightly affected by atmospheric phenomena
• Destruction of a single satellite would be difficult and expensive
• High degree of freedom from jamming
• Lower probability of both detection and interception

Question 14

ID the 2 single channel radio tactical satellite bandwidths/waveforms most commonly used with USMC multi-band radios

Answer 14

• 5 kHz

- 25 kHz

Question 15

ID the purpose of Demand Assigned Multiple Access (DAMA) operation

Answer 15

Increase loading of limited SATCOM channels by assigning channels as needed by terminal users for their communication needs

Question 16

Select from a list of distractors the 2 addresses required for Demand Assigned Multiple Access operation

Answer 16

• Terminal base address

- Network address

Question 17

ID the characteristics of Time Division Multiple Access (TDMA)

Answer 17

• Divides the signal into different time slots. The users transmit in rapid succession, one after the other, each using their own time slot
• TDMA is the channel access method used with DAMA

Question 18

ID the characteristics of Frequency Division Multiple Access (FDMA)

Answer 18

• FDMA gives users an individual allocation of one or several entire frequency bands within a channel
• Provides users a small amount of bandwidth all of the time

Question 19

ID the purpose of retransmission

Answer 19

Extends single channel communications around obstacles and across increased distances

• Increase distance
• Overcome obstacle

Question 20

ID the 2 types of retransmission

Answer 20

1. Automatic

2. Manual

Question 21

ID the 3 modes of retransmission capable in the SINCGARS radio system

Answer 21

1. Frequency Hop to Frequency Hop
2. Frequency Hop to Single Channel
3. Single Channel to Single Channel

Question 22

ID the modes of retransmission capable in the different USMC multiband radios

Answer 22

1. VHF/UHF SC
2. Dedicated SATCOM
3. FH

Question 23

ID the characteristics of the J-1077 Junction Box

Answer 23

• Two CX-4566 connections

- 26 binding post pairs

Question 24

ID the 2 most common guided media used to extend services from antenna hill to the COC

Answer 24

• CX-4566

- WD-1A/TT

Question 25

Given a radio system, ID the radio remote control unit used to extend voice services from an antenna hill to a COC

Answer 25

RF-5800R: PRC-150 PRC-117F RF-7800R-RC: FALCON II FALCON III (All Harris radios in use by the Marine Corps) AN/GRA-39: SINCGARS Harris C-11561 RCU: SINCGARS only RT-1523C/D/E: SINCGARS only

Question 26

Given a scenario with Equipment Density List, correctly organize the equipment string to extend voice services from antenna hill to a COC

Answer 26

Antenna > Coax > Radio > WD-1 > LCU > CX-4566 > RCU > WD-1 > SRCU