Ham Radio General Class Practice Test

Approximately how long is each leg of a symmetrical delta-loop antenna?

1. 1/4 wavelength

2. 1/3 wavelength

3. 1/2 wavelength

4. 2/3 wavelength

The correct answer is: 1/3 wavelength

A symmetrical delta-loop antenna is typically a triangular shape and is resonant at a frequency determined by the length of its sides. For optimal performance, each leg of a symmetrical delta-loop antenna is designed to be approximately 1/3 wavelength long. This design allows the antenna to exhibit good radiation patterns and efficiency. When constructing a delta-loop antenna, the dimensions are essential to achieving the desired resonance and performance in the desired frequency range. If each leg is 1/3 wavelength, then the total perimeter of the loop corresponds to a wavelength, which is the necessary condition for a full-wave loop antenna. This allows the antenna to utilize the principles of resonance effectively, maximizing its capability in transmitting and receiving signals at the targeted frequencies. Other lengths mentioned, such as 1/4 wavelength, 1/2 wavelength, or 2/3 wavelength, do not align with the standard configuration for a symmetrical delta-loop. While different lengths can be used for specialized designs or different types of antennas, the general consensus for standard symmetrical delta loops is for each leg to measure about 1/3 wavelength.