24
3-45. Of the following amplifiers, which one
has a high gain, low noise, wide
bandwidth and is operated in the
microwave region?
1. A magnetic
2. An operational
3. A differential
4. A traveling-wave-tube
3-46. In a line-of-sight communications
system, propagation is affected by which
of the following layers of the
atmosphere?
1. Ionosphere
2. Troposphere
3. Stratosphere
4. Thermosphere
3-47. Horn-driven paraboloid antennas have
which of the following characteristics?
1. High gain, narrow beam width
2. Low gain, narrow beam width
3. High gain, wide beam width
4. Low gain, wide beam width
3-48. Line-of-sight systems are configured in
many ways with regards to channel width
and number of channels. A voice system
with a channel width of 4-kilohertz has a
total of how many channels available for
transmission?
1.
200
2.
400
3.
600
4.
800
3-49. A one-hop transmission of a tropo-scatter
system can travel what maximum
distance?
1. 1200 miles
2. 1000 miles
3. 800 miles
4. 500 miles
3-50. Of the following advantages, which one
is primary to the NTDS when compared
with conventional data systems?
1. Speed
2. Distance
3. Security
4. Reliability
3-51. The NTDS uses which of the following
data transmission links?
1. 14, 11, 4A
2. 14A, 11, 4
3. 14, 11A, 4
4. 14A, 11A, 4A
3-52. Of the following NTDS links, which
one(s) is/are only used as a one-way
broadcast?
1. 14
2. 4A
3. 11, 14
4. 4A, 11
3-53. Portable radio sets are used primarily for
which of the following types of
communications?
1. Amphibious
2. Air-to-air
3. Electronic warfare
4. Anti-submarine warfare
3-54. When designing portable and pack
radios, which of the following
characteristics is the prime
consideration?
1. Must be solar powered
2. Must be heavy and rugged
3. Must have high output power
4. Must be light-weight and compact
