Radio Wave Propagation Quiz - ELEMENT V

What does the term "critical angle" mean as used in radio wave propagation?

• The highest takeoff angle that will return a radio wave to the Earth under specific ionospheric conditions

• The angle at which a radio wave must be transmitted to reach the horizon

• The angle at which a radio wave must be transmitted to reach the ionosphere

• The angle at which a radio wave must be transmitted to pass through the ionosphere

When a double balanced mixer is injected with an RF carrier and an audio signal, it normally yields

• single sideband with carrier

• double sideband with carrier

• double sideband with no carrier

• single sideband with no carrier

What is the approximate length of a full-wave loop antenna for 21.005 MHz?

• 0.33 meter

• 14.3 meter

• 1 meter

• 22.2 meters

Key clicks in CW reception is caused by _______ .

• using a poor antenna

• over-driving the final amplifier

• using a low power transmitter

• having a short antenna

Which of the following phone emissions uses the narrowest frequency bandwidth?

• AM

• FM

• Single sideband

• Double sideband

Signal to noise ratio (SNR) is _________ .

• The signal power is added to noise power

• the difference between the highest and lowest signal

• the signal power divided by the bandwidth

• none of the above

Answer explanation

The ratio of the power of a signal to the power of noise

Which of the following is an advantage of a horizontally polarized as compared to vertically polarized HF antenna?

• Higher gain

• Better ground reflection

• Lower ground reflection losses

• Easier to install

Which transmission has the narrowest bandwith?

• F3E

• J3E

• A1A

• F1B

For satellite and space communications, the ideal wave polarization is ______ .

• linear

• horizontal

• vertical

• circular

What problem can occur when making measurements on an antenna system with an antenna analyzer?

• Weak signals from the transmitter

• Strong signals from nearby transmitters can affect the accuracy of measurements

• High power output from the antenna

• Interference from digital signals