SS0014 Practice Exercise Answer Key & Review
Lesson 1: Employment of Tactical Radio Sets
Situation: You are conducting a training session on tactical radio applications and field expedient antennas.
| 1. |
Which of the following SINCGARS configurations is a retransmission radio?
| |
D. AN/VRC-92.
The AN/VRC-92 is the SINCGARS version of the retransmission configuration and is replacing the AN/VRC-45 and -49 retransmission sets. |
|
| 2. |
How can you make your field-expedient long wire antenna unidirectional?
| |
B. Add a terminating resistor to the free end.
Adding a terminating resistor to the free end of the antenna allows the antenna to resonate in one direction only and forces it to be unidirectional in the direction of the terminated end. |
|
|
| 3. |
Which of the following units is most likely to require a point-to-point communications system?
| |
D. A long-range surveillance company making time-critical intelligence reports.
Each of the other three units has a net that it makes normal reports on. Furthermore the information being passed by these units is not time critical. The surveillance company has to be able to pick up the radio and be in immediate contact with the command post. It is therefore the most likely unit to require a point-to-point communications system. |
|
|
| 4. |
You are constructing a long-wire antenna three wavelengths long to communicate on a channel frequency of 29.274 MHz. How long should you make your antenna?
| |
C. 100.0 feet.
Three wavelengths is six half-wavelengths. Using the formula for long-wire antennas gives:
LENGTH (in feet) =
LENGTH = 100 feet.
|
|
|
| 5. |
You are using the AN/VRC-43 set to communicate with a special forces unit that is using the AN/PRC-70 set. The unit moves over a large hill, cutting off communications. Which of the following radio sets should you use to reestablish communications with the unit?
| |
B. AN/GRC-106.
Since communications was cut off as the unit moved over the hill, you have an indication that the direct path of communication is no longer available. Most VHF communications take place along the direct path, so you must try another propagation path to communicate with the unit. The AN/GRC-106 is an HF radio, so it can use the sky-wave transmission path. The AN/PRC-70 has the capability to communicate in both HF and VHF bands and using both AM and FM modes. This feature makes it capable of taking advantage of whatever communications paths and equipment are available. |
|
|
| 6. |
While the special forces unit is still on the other side of the large hill, it experiences a failure in its AN/PRC-70 set. Which of the following sets can the unit use to reestablish communications with you?
| |
C. AN/PRC-74.
The unit is still out of the range of a VHF line-of-sight radio. If their AN/PRC-70 fails, they must use some other HF AM radio set. The AN/PRC-74 is the only choice that matches those criteria. |
|
|
| 7. |
You are directed to set up a net radio interface using your AN/VRC-12 series radio. Which of the following pieces of auxiliary equipment should you use to accomplish this?
| |
A. AN/GSA-7.
The unit is still out of the range of a VHF line-of-sight radio. If their AN/PRC-70 fails, they must use some other HF AM radio set. The AN/PRC-74 is the only choice that matches those criteria. |
|
|
| 8. |
While you are in your exercise area, some civilian trucks with citizens' band radios enter your exercise area. Which radio set should you use to inform them that they are in a restricted area?
|
| |
C. AN/FRC-93.
The AN/FRC-93 is a military derivative of the commercial citizens' band radio. The other choices are all VHF radios and would not be compatible with the truck's radios.
|
|
GO TO:
Lesson 2
Table of Contents
