Ham Radio General Class Practice Test

What does the term "SWR" stand for in amateur radio?

1. Sample Wave Ratio

2. Standing Wave Ratio

3. Synchronous Wave Ratio

4. Standard Wave Ratio

The correct answer is: Standing Wave Ratio

The term "SWR" stands for "Standing Wave Ratio." This term is essential in amateur radio because it relates to how well the antenna is matched to the feedline and the transmitter. A standing wave occurs when waves traveling along the feedline are reflected back due to impedance mismatches, resulting in a pattern of nodes and antinodes along the feedline. Measuring the SWR helps operators determine how efficiently power is being transmitted from the transmitter to the antenna. A lower SWR indicates that more power is being radiated by the antenna and less is being reflected back toward the transmitter, which can prevent damage to the radio equipment and ensure effective communication. Understanding SWR is crucial for tuning antenna systems, as a high SWR can lead to inefficient operation and potential damage. Therefore, recognizing that SWR stands for "Standing Wave Ratio" provides important insight into the performance and functionality of radio equipment in amateur radio operations.