Free Radio Wave Propagation & Modulation Questions and Answers

Question 1

What type of wave propagation is most commonly associated with VHF and UHF frequencies?

Accepted Answer

Line-of-sight

Answer

Skywave

Answer

Ground wave

Answer

Surface wave

Question 2

Which ionospheric layer is most responsible for long-distance HF communication during the day?

Accepted Answer

F2 layer

Answer

D layer

Answer

E layer

Answer

F1 layer

Question 3

What is modulation in the context of radio transmissions?

Accepted Answer

Adding information to a carrier wave

Answer

Boosting signal power

Answer

Tuning to a frequency

Answer

Grounding the transmitter

Question 4

Which type of modulation varies the amplitude of the carrier wave?

Accepted Answer

Amplitude Modulation

Answer

Frequency Modulation

Answer

Phase Modulation

Answer

Pulse Modulation

Question 5

What happens to radio waves when they encounter the ionosphere?

Accepted Answer

They are refracted or reflected

Answer

They always get absorbed

Answer

They reflect off the Earth's surface

Answer

They stay in one place

Question 6

Which of the following frequencies is most likely to be refracted by the ionosphere for long-distance communication?

Accepted Answer

14 MHz

Answer

30 MHz

Answer

50 MHz

Answer

144 MHz

Question 7

Which type of modulation is known for its resistance to signal noise and interference?

Accepted Answer

FM

Answer

AM

Answer

CW

Answer

SSB

Question 8

What is a skip zone in radio communication?

Accepted Answer

A region where radio signals cannot be received

Answer

A frequency band with no users

Answer

A power outage region

Answer

A noise-free zone

Question 9

Which term describes the bending of radio waves around obstacles?

Accepted Answer

Diffraction

Answer

Reflection

Answer

Refraction

Answer

Absorption