Ham Radio General Class Practice Test

What type of antenna is typically used for better low-angle radiation?

1. Vertical antenna

2. Shortened antenna

3. Dipole antenna

4. Yagi antenna

The correct answer is: Vertical antenna

A vertical antenna is typically utilized for better low-angle radiation due to its radiation pattern characteristics. This type of antenna can effectively launch radio waves close to the horizon, making it particularly advantageous for long-distance communications, especially on the HF bands. The vertical orientation allows the antenna to radiate signals in a horizontal plane, which is especially effective for propagation over ground and sky-wave communications. Vertical antennas are often designed to be ground-mounted and can utilize a ground plane or radial system to enhance their performance. The low-angle radiation tends to improve the signal reach in the far field, making vertical antennas a popular choice for many amateur radio operators looking to achieve DX (long-distance) communication. While the other antenna types have their own specific uses and advantages, they do not excel in low-angle radiation to the same extent. For instance, dipole antennas can radiate effectively in various directions but usually provide higher angles of radiation for most configurations. Yagi antennas, while directional and excellent for specific communications, are generally designed for higher angle radiation in the direction they are pointed. Shortened antennas may provide compactness but often compromise on performance compared to full-sized vertical antennas.