No Nonsense Extra Class License Study Guide: for tests given between July 2020 and June 2024

The “No Nonsense” series of amateur radio license study guides has become famous for helping people pass the tests. Written in a simple, easy-to-understand style, this study guide will help you upgrade to Amateur Extra Class in no time. It covers every question in the 2020 question pool. and not only gives you the correct answer, but explains the answer in a very straightforward way. Here's an example:The radiation resistance of an antenna is the value of a resistance that would dissipate the same amount of power as that radiated from an antenna. In the case of an antenna, however, that power isn’t being turned into heat, but rather turned into radio waves. The total resistance of an antenna system is the sum of the radiation resistance and ohmic resistance. The ohmic resistance is the combination of all the physical resistances in the system, including the resistance of the antenna wire, feed line, and connections.QUESTION: What is the radiation resistance of an antenna? (E9A03)ANSWER: The value of a resistance that would dissipate the same amount of power as that radiated from an antennaQUESTION: What is included in the total resistance of an antenna system? (E9A05)ANSWER: Radiation resistance plus loss resistanceIf you know the radiation resistance and the ohmic resistance of an antenna, you can calculate its efficiency. Antenna efficiency equals the radiation resistance divided by the total resistance. QUESTION: What is antenna efficiency? (E9A09)ANSWER: Radiation resistance divided by total resistanceKB6NU's "No Nonsense" study guides have helped thousands get their amateur radio licenses or upgrade to General or Extra. They can help you, too.