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- FCC General Exam Question Pool. Subelement 3BC.
- Radio Wave Propagation. 3 Questions.
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- 3C 1.6 C
- What is the maximum distance along the Earth's surface
- that can normally be covered in one hop using the F2 layer?
-
- A. Approximately 180 miles.
- B. Approximately 1200 miles.
- C. Approximately 2500 miles.
- D. No distance. This layer does
- not support radiocommunication.
-
-
- 3C 1.7 B
- What is the maximum distance along the Earth's surface
- that can be covered in one hop using the E layer?
-
- A. Approximately 180 miles.
- B. Approximately 1200 miles.
- C. Approximately 2500 miles.
- D. No distance. This layer does
- not support radiocommunication.
-
-
- 3C 1.9 B
- What is the average height of maximum ionization of the E Layer?
-
- A. 45 miles.
- B. 70 miles.
- C. 200 miles.
- D. 1200 miles.
-
-
- 3C 1.10 A
- During what part of the day, and in what season of the year
- can the F2 Layer be expected to reach its maximum height?
-
- A. At Noon during the Summer.
- B. At Midnight during the Summer.
- C. At Dusk in the Spring and Fall
- D. At Noon during the Winter.
-
-
- 3C 1.13 D
- What is the CRITICAL ANGLE, as used in radio wave propagation?
-
- A. The lowest take off angle that will return a radio
- wave to Earth under specific Ionospheric conditions.
- B. The compass direction of the desired
- DX station from your location.
- C. The 180 degree inverted compass direction of the
- desired DX station from your location.
- D. The highest take off angle that will return a radio
- wave to Earth during specific Ionospheric conditions.
-
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- 3C 2.3 C
- What is the main reason that the 160, 80 and 40 meter
- Amateur Bands can be used only for short distance
- communications during daylight hours?
-
- A. Because of a lack of activity.
- B. Because of Auroral propagation.
- C. Because of D Layer absorption.
- D. Because of magnetic flux.
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- 3C 2.4 C
- What is the principal reason that the 160
- through 40 meter bands are useful only for short
- distance communications during daylight hours?
-
- A. F Layer bending.
- B. Gamma radiation.
- C. D Layer absorption.
- D. Tropospheric ducting.
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- 3C 3.3 B
- If the maximum usable frequency on the path from
- Minnesota to Africa is 22 MHz., which band should
- offer the best chance for a successful contact?
-
- A. 10 meters.
- B. 15 meters.
- C. 20 meters.
- D. 40 meters.
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- 3C 3.4 C
- If the maximum usable frequency on the path from
- Ohio to West Germany is 17 MHz., which band should
- offer the best chance for a successful contact?
-
- A. 80 meters.
- B. 40 meters.
- C. 20 meters.
- D. 2 meters.
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- 3C 5.1 B
- Over what periods of time do Sudden
- Ionospheric Disturbances normally last?
-
- A. The entire day.
- B. A few minutes to a few hours.
- C. A few hours to a few days.
- D. Approximately one week.
-
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- 3C 5.2 A
- What can be done at an amateur station to continue
- radiocommunications during a Sudden Ionospheric Disturbance?
-
- A. Try a higher frequency.
- B. Try the other sideband.
- C. Try a different antenna polarization.
- D. Try a different frequency shift.
-
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- 3C 5.3 B
- What effect does a Sudden Ionospheric Disturbance have on the
- daylight Ionospheric propagation of HF radio waves?
-
- A. Disrupts higher latitude paths
- more than lower latitude paths.
- B. Disrupts transmissions on lower frequencies
- more than those on higher frequencies.
- C. Disrupts communiations via satellite
- more than direct communications.
- D. None. Only dark (as in nighttime) areas
- of the globe are affected.
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- 3C 5.4 C
- How long does it take a Solar Disturbance that
- increases the Sun's ultraviolet radiation to
- cause Ionospheric Disturbances on Earth?
-
- A. Instantaneously.
- B. 1.5 Seconds.
- C. 8 Minutes.
- D. 20 to 40 Hours.
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- 3C 5.5 A
- Sudden Ionospheric Disturbances occur as a result of
- radio wave absorption in which layer of the Ionosphere?
-
- A. D layer.
- B. E layer.
- C. F1 layer.
- D. F2 layer.
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- 3C 6.2 B
- What is a characteristic of BACKSCATTER signals?
-
- A. High intelligibility.
- B. A wavering sound.
- C. Reversed modulation.
- D. Reversed sidebands.
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- 3C 6.4 D
- What makes backscatter signals often sound distorted?
-
- A. Auroral activity and changes in the Earth's magnetic field.
- B. The propagation through ground waves
- that absorb much of the signal's clarity.
- C. The Earth's E Layer at the point of radio wave refraction.
- D. The small part of the signal's energy scattered back to
- the transmitter skip zone through several radio wave paths.
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- 3C 6.5 B
- What is the radio wave propagation phenomenon that allows
- a signal to be detected at a distance too far for ground
- wave propagation but too near for normal sky wave propagation.
-
- A. Ground wave.
- B. Scatter.
- C. Sporadic E skip.
- D. Short path skip.
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- 3C 6.6 D
- When does Ionospheric scatter propagation
- on the HF bands most often occur?
-
- A. When the sunspot cycle is at a minimum.
- B. At night.
- C. When the F1 and F2 layers are combined.
- D. At frequencies above the maximum usable frequency.
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- 3C 7.1 B
- What is SOLAR FLUX?
-
- A. The density of the Sun's magnetic field.
- B. The radio energy emitted by the sun.
- C. The number of sunspots on the side
- of the Sun facing the Earth.
- D. A measure of the tilt of the Earth's
- Ionosphere on the side toward the Sun.
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- 3C 7.2 D
- What is the SOLAR FLUX INDEX?
-
- A. A measure of past measurements of solar activity.
- B. A measurement of solar activity that compares daily
- readings with results from the last six months.
- C. Another name for the American Sunspot Number.
- D. A measure of solar activity that is taken daily.
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- 3C 7.3 A
- What is a timely indicator of solar activity?
-
- A. The 2300 MHz. Solar Flux Index.
- B. The Mean Canadian Sunspot Number.
- C. A clock set to Coordinated Universal Time.
- D. Van Allen Radiation measurements taken at Boulder, Colorado.
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- 3C 7.4 D
- What type of propagation conditions on the 15 meter band
- is indicated by a Solar Flux Index of 60 to 70?
-
- A. Unpredictable Ionospheric propagation.
- B. No Ionospheric propagation is possible.
- C. Excellent Ionospheric propagation.
- D. Poor Ionospheric propagation.
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- 3C 7.5 D
- A Solar Flux Index of 90 to 110 indicates what type
- of propagation conditions on the 15 meter band?
-
- A. Poor Ionospheric propagation.
- B. No Ionospheric propagation is possible.
- C. Unpredictable Ionospheric propagation.
- D. Good Ionospheric propagation.
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- 3C 7.6 A
- A Solar Flux Index of greater than 120 would indicate
- what type of propagation conditions of the 10 meter band?
-
- A. Good Ionospheric propagation.
- B. Poor Ionospheric propagation.
- C. No Ionospheric propagation is possible.
- D. Unpredictable Ionospheric propagation.
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- 3C 7.7 D
- For widespread long distance openings on the 6 meter band,
- what Solar Flux values would be required?
-
- A. Less than 50.
- B. Approximately 75.
- C. Greater than 100.
- D. Greater than 250.
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- 3C 7.8 C
- If the MUF is high and HF radiocommunications are
- generally good for several days, a similar condition
- can usually be expected how many days later?
-
- A. 7 days.
- B. 14 days.
- C. 28 days.
- D. 90 days.
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- 3C 10.1 D
- What is a GEOMAGNETIC DISTURBANCE?
-
- A. A sudden drop in the Solar Flux Index.
- B. A shifting of the Earth's magnetic pole.
- C. Ripples in the Ionosphere.
- D. A dramatic change in the Earth's magnetic field
- over a short period of time.
-
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- 3C 10.2 A
- Which latitude paths are more susceptible
- to Geomagnetic Disturbances?
-
- A. Those greater than 45 degrees latitude.
- B. Those less than 45 degrees latitude.
- C. Equatorial paths.
- D. All paths are affected equally.
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- 3C 10.3 B
- What can be the effect of a major
- geomagnetic storm on radiocommunications?
-
- A. Improved high latitude HF communications.
- B. Degraded high latitude HF communications.
- C. Improved ground wave propagation.
- D. Improved chances of ducting at UHF.
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- 3C 10.4 D
- How long does it take a Solar Disturbance that
- increases the Sun's radiation of charged particles
- to affect radio wave propagation on Earth?
-
- A. The effect is instantaneous.
- B. 1.5 Seconds.
- C. 8 Minutes.
- D. 20 to 40 Hours.
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- End of Subelement 3BC.
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