Deep Dive: G9B01
The correct answer is B: Station equipment may carry significant RF current. A characteristic of a random-wire HF antenna connected directly to the transmitter is that station equipment may carry significant RF current. Random-wire antennas don't have proper impedance matching, so RF current flows on feed lines and equipment. For amateur radio operators, this is a safety and interference concern. Understanding this helps when using random-wire antennas.
Why Other Answers Are Wrong
Option A: Incorrect. Random-wire doesn't have to be longer than 1 wavelength - it can be various lengths. Length requirement isn't the characteristic. Option C: Incorrect. Random-wire doesn't produce only vertically polarized radiation - polarization depends on wire orientation, not just vertical. Only vertical isn't correct. Option D: Incorrect. Random-wire isn't more effective on lower bands - effectiveness depends on length and matching, not specifically lower bands. Lower band effectiveness isn't the characteristic.
Exam Tip
Random-wire antenna characteristic = station equipment may carry significant RF current. Think 'R'andom-'W'ire = 'R'F 'W'anders onto equipment. Random-wire antennas don't have proper matching, so RF current flows on feed lines and equipment. Not length requirement, not only vertical, not lower bands - just RF current on equipment.
Memory Aid
Random-wire antenna characteristic = station equipment may carry significant RF current. Think 'R'andom-'W'ire = 'R'F 'W'anders. Random-wire antennas don't have proper matching, so RF current flows on equipment. Safety and interference concern.
Real-World Example
A random-wire antenna connected directly to a transmitter: The antenna doesn't have proper impedance matching, so RF current flows on the feed line, transmitter chassis, and other equipment. This can cause RF burns, interference, and equipment problems. This is why random-wire antennas need proper RF grounding and isolation. Station equipment may carry significant RF current.
Source & Coverage
Question Pool: 2023-2027 Question Pool
Subelement: G9B
Reference: 2023-2027 Question Pool · G9 - Antennas and Feed Lines
Key Concepts
Verified Content
Question from the official FCC General Class pool. Explanation reviewed by licensed amateur radio operators and mapped to the G9B topic.