Basic Qualification · B-006 Feedlines and antenna systems · B-006-005-003
What is the most likely cause of erratic readings on an SWR meter?
- A Intermittent connection in the antenna system
- B Transmitting into the wrong antenna
- C Interference from electrical power lines
- D Lack of a balun at the antenna feed point
Correct answer: A — Intermittent connection in the antenna system. From the official ISED question bank, verified word for word.
Why
An intermittent connection means a wire or joint is loose, causing the electrical path to break and reconnect rapidly. The full explanation — and one for every question — is in Pro.
Practise this section
Getting the signal out: antennas, feedlines, SWR, baluns, matching, and why antenna length depends on frequency.