What is a characteristic of a random-wire HF antenna connected directly to the transmitter?
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.
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 Application
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.
Key Concepts
Why Other Options 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.
题目解析
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.
考试技巧
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.
记忆口诀
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.
实际应用示例
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.
错误选项分析
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.
知识点
Random-wire antenna, RF current, Station equipment, Direct connection
Verified Content
Question from official FCC General Class question pool. Explanation reviewed by licensed amateur radio operators.