Ham Radio General Class Test FREE Ham Radio General Class Test Antennas and Feed Lines Questions and Answers 3

Question 1

What is the effect of conductor losses in a feed line operating at UHF frequencies compared to HF frequencies?

Accepted Answer

Losses are significantly higher at UHF

Answer

Losses are significantly lower at UHF

Answer

Losses are identical at both frequency ranges

Answer

Losses only occur at HF, not UHF

Question 2

What is the typical characteristic impedance of window line (ladder line)?

Accepted Answer

450 ohms

Answer

50 ohms

Answer

75 ohms

Answer

300 ohms

Question 3

Which antenna configuration would provide the lowest angle of radiation for DX contacts on HF?

Accepted Answer

A horizontal dipole mounted at one wavelength above ground

Answer

A horizontal dipole mounted at one-quarter wavelength above ground

Answer

A vertical dipole with no ground plane

Answer

A horizontal dipole mounted at one-eighth wavelength above ground

Question 4

What is the approximate gain of a three-element Yagi antenna over a dipole?

Accepted Answer

6 dBd

Answer

1 dBd

Answer

15 dBd

Answer

25 dBd

Question 5

What is the primary purpose of a transmission line stub used in an antenna system?

Accepted Answer

To provide impedance matching or filtering at a specific frequency

Answer

To increase the power handling capacity of the feed line

Answer

To extend the physical length of the antenna

Answer

To convert between horizontal and vertical polarization

Question 6

What is the result of operating a coaxial feed line well above its rated maximum frequency?

Accepted Answer

Excessive signal loss due to increased attenuation

Answer

The cable radiates more power than the antenna

Answer

The characteristic impedance doubles

Answer

The velocity factor drops to zero