Ham Amateur Radio Technician Practice Exam

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

1. Higher elevation gain

2. Less interference from man-made noise

3. Lower ground losses

4. Better for long-distance communication

The correct answer is: Lower ground losses

Using a horizontally polarized antenna offers several advantages, particularly in terms of ground losses. Horizontally polarized antennas generally experience lower ground losses when installed at a sufficient height above the ground. This is due to their radiation pattern and the way they interact with the earth's surface and the ionosphere. In a horizontally polarized setup, the electromagnetic waves emitted by the antenna are oriented parallel to the ground. This orientation allows for a more efficient wave propagation over various terrains, as the energy radiated tends to be less absorbed by the ground compared to vertically polarized waves, which can be more affected by ground conductivity and moisture variations. Additionally, horizontally polarized antennas can be less susceptible to multi-path interference, which can occur when signals bounce off of surfaces and arrive at the receiver at different times. This aspect is particularly beneficial for long-distance communication, as it can lead to clearer reception. While other options may appear beneficial in certain contexts, they do not provide the same level of efficiency and reduced loss that a horizontally polarized antenna offers when considering overall performance and reliability in various communication scenarios.