Ham Amateur Radio Technician Practice Exam

The feed point impedance of an end-fed half-wave antenna is indeed very high, often in the range of hundreds or thousands of ohms. This high impedance occurs because the antenna is designed to be resonant at a specific frequency. When the antenna is cut to a half-wavelength for that frequency, it presents this high impedance at the feed point. In an end-fed configuration, the feed point is located at one end of the antenna, and due to its length and how it interacts with the surrounding environment, the impedance seen at this point is elevated. Antennas with high feed point impedance require adjustments, such as an impedance matching transformer (also known as a balun or unun), to match the impedance to the typical 50 ohm input of most radio transmitters. This contextualizes why options like very low, moderate, and standard 50 ohms do not describe the feed point impedance accurately; they misrepresent the characteristics of the end-fed half-wave antenna's design and functionality.